ADC12130, ADC12132, ADC12138
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ADC12130/ADC12132/ADC12138 Self-Calibrating 12-Bit Plus Sign Serial I/O A/D
Converters with MUX and Sample/Hold
Check for Samples: ADC12130,ADC12132,ADC12138
1FEATURES DESCRIPTION
NOTE: Some device/package combinations are
2 Serial I/O (MICROWIRE, SPI and QSPI obsolete and are described and shown here for
Compatible) reference only. See our web site for product
Power Down Mode availability.
Programmable Acquisition Time The ADC12130, ADC12132 and ADC12138 are 12-
Variable Digital Output Word Length and bit plus sign successive approximation Analog-to-
Format Digital converters with serial I/O and configurable
input multiplexer. The ADC12132 and ADC12138
No Zero or Full Scale Adjustment Required have a 2 and an 8 channel multiplexer, respectively.
0V to 5V Analog Input Range with Single 5V The differential multiplexer outputs and ADC inputs
Power Supply are available on the MUXOUT1, MUXOUT2, A/DIN1
and A/DIN2 pins. The ADC12130 has a two channel
APPLICATIONS multiplexer with the multiplexer outputs and ADC
inputs internally connected. The ADC12130 family is
Pen-Based Computers tested and specified with a 5 MHz clock. On request,
Digitizers these ADCs go through a self calibration process that
Global Positioning Systems adjusts linearity, zero and full-scale errors to typically
less than ±1 LSB each.
KEY SPECIFICATIONS The analog inputs can be configured to operate in
Resolution 12-bit plus sign various combinations of single-ended, differential, or
pseudo-differential modes. A fully differential unipolar
12-Bit plus sign conversion time 8.8 μs (max) analog input range (0V to +5V) can be
12-Bit plus sign throughput time 14 μs (max) accommodated with a single +5V supply. In the
Integral Linearity Error ±2 LSB (max) differential modes, valid outputs are obtained even
when the negative inputs are greater than the positive
Single Supply 3.3V or 5V ±10% because of the 12-bit plus sign output data format.
Power Consumption The serial I/O is configured to comply with NSC
+3.3V 15 mW (max) MICROWIRE. For voltage references, see the
+3.3V power down 40 μW (typ) LM4040, LM4050 or LM4041.
+5V 33 mW (max)
+5V power down 100 μW (typ)
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2000–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
ADC12130, ADC12132, ADC12138
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ADC12138 Simplified Block Diagram
Connection Diagrams
Top View Top View
Figure 1. 16-Pin MDIP and Figure 2. 20-Pin SSOP Package
Wide Body SOIC Packages See Package Number DB0020A
See Package Number NFG0016E and DW0016B
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Top View
Figure 3. 28-Pin MDIP, SSOP and
Wide Body SOIC Packages
See Package Numbers N28B, DB0028A, and DW0028B
Some of these product/package combinations are obsolete and are shown here for reference only. Check the TI
web site for availability.
PIN DESCRIPTIONS
Pin Name Pin Description
Analog Inputs to the MUX (multiplexer). A channel input is selected by the address information at the DI pin, which
is loaded at the rising edge of SCLK into the address register (see Table 2 and Table 3). The voltage applied to
CH0 thru CH7 these inputs should not exceed VA+ or go below VA- or below GND. Exceeding this range on an unselected
channel may corrupt the reading of a selected channel.
COM Analog input pin that is used as a pseudo ground when the analog multiplexer is single-ended.
MUXOUT1 Multiplexer Output pins. If the multiplexer is used, these pins should be connected to the A/DIN pins, directly or
MUXOUT2 through an amplifier and/of filter.
Converter Input pins. MUXOUT1 is usually tied to A/DIN1. MUXOUT2 is usually tied to A/DIN2. If external circuitry
A/DIN1 is placed between MUXOUT1 and A/DIN1, or MUXOUT2 and A/DIN2, it may be necessary to protect these pins
A/DIN2 against voltage overload. The voltage at these pins should not exceed VA+or go below AGND (see Figure 64).
Data Output pin. This pin is an active push/pull output when CS is low. When CS is high, this output is TRI-STATE.
The conversion result (DB0–DB12) and converter status data are clocked out at the falling edge of SCLK on this
DO pin. The word length and format of this result can vary (see Table 1). The word length and format are controlled by
the data shifted into the multiplexer address and mode select register (see Table 4).
Serial Data Input pin. The data applied to this pin is shifted at the rising edge of SCLK into the multiplexer address
DI and mode select register. Table 2 through Table 4 show the assignment of the multiplexer address and the mode
select data.
This pin is an active push/pull output which indicates the status of the ADC12130/2/8.A logic low on this pin
EOC indicates that the ADC is busy with a conversion, Auto Calibration, Auto Zero or power down cycle. The rising edge
of EOC signals the end of one of these cycles
A logic low is required at this pin to program any mode or to change the ADC's configuration as listed in Mode
Programming (Table 4). When this pin is high, the ADC is placed in the read data only mode. While in the read data
only mode, bringing CS low and pulsing SCLK will only clock out the data stored in the ADCs output shift register.
CONV The data at DI will be ignored. A new conversion will not be started and the ADC will remain in the mode and/or
configuration previously programmed. Read data only cannot be performed while a conversion, Auto Cal or Auto
Zero are in progress.
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PIN DESCRIPTIONS (continued)
Pin Name Pin Description
Chip Select input pin. When a logic low is applied to this pin, the rising edge of SCLK shifts the data at the DI input
into the address register and brings DO out of TRI-STATE. With CS low, the falling edge of SCLK shifts the data
resulting from the previous ADC conversion out at the DO output, with the exception of the first bit of data. When
CS is low continuously, the first bit of the data is clocked out on the rising edge of EOC (end of conversion). When
CS is toggled, the falling edge of CS always clocks out the first bit of data. CS should be brought low while SCLK is
low. The falling edge of CS interrupts a conversion in progress and starts the sequence for a new conversion.
CS When CS is brought low during a conversion, that conversion is prematurely terminated and the data in the output
latches may be corrupted. Therefore, when CS is brought low during a conversion in progress, the data output at
that time should be ignored. CS may also be left continuously low. In this case, it is imperative that the correct
number of SCLK pulses be applied to the ADC in order to remain synchronous. After the ADC supply power is
applied, the device expects to see 13 clock pulses for each I/O sequence. The number of clock pulses the ADC
expects is the same as the digital output word length. This word length can be modified by the data shifted in at the
DO pin. Table 4 details the data required.
Data Output Ready pin. This pin is an active push/pull output which is low when the conversion result is being
DOR shifted out and goes high to signal that all the data has been shifted out.
Serial Data Clock input. The clock applied to this input controls the rate at which the serial data exchange occurs.
The rising edge loads the information at the DI pin into the multiplexer address and mode select shift register. This
address controls which channel of the analog input multiplexer (MUX) is selected and the mode of operation for the
ADC. With CS low, the falling edge of SCLK shifts the data resulting from the previous ADC conversion out on DO,
SCLK with the exception of the first bit of data. When CS is low continuously, the first bit of the data is clocked out on the
rising edge of EOC (end of conversion). When CS is toggled, the falling edge of CS always clocks out the first bit of
data. CS should be brought low when SCLK is low. The rise and fall times of the clock edges should not exceed
1μs.
Conversion Clock input. The clock applied to this input controls the successive approximation conversion time
CCLK interval and the acquisition time. The rise and fall times of the clock edges should not exceed 1 μs.
Positive analog voltage reference input. In order to maintain accuracy, the voltage range of VREF (VREF = VREF+
VREF+ VREF) is 1.0 VDC to 5.0 VDC and the voltage at VREF+ cannot exceed VA+. See Figure 63 for recommended
bypassing.
The negative analog voltage reference input. In order to maintain accuracy, the voltage at this pin must not go
VREF-below GND or exceed VREF+. (See Figure 63).
Power Down pin. When PD is high the ADC is powered down; when PD is low the ADC is powered up, or active.
PD The ADC takes a maximum of 700 μs to power up after the command is given.
These are the analog and digital power supply pins. VA+and VD+are not connected together on the chip. These
VA+pins should be tied to the same supply voltage and bypassed separately (see Figure 63). The operating voltage
VD+range of VA+ and VD+ is 3.0 VDC to 5.5 VDC.
DGND The digital ground pin (see Figure 63).
AGND The analog ground pin (see Figure 63).
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
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Absolute Maximum Ratings (1)(2)
Positive Supply Voltage
(V+= VA+=VD+) 6.5V
Voltage at Inputs and Outputs
except CH0–CH7 and COM 0.3V to V++0.3V
Voltage at Analog Inputs
CH0–CH7 and COM GND 5V to V++5V
|VA+VD+| 300 mV
Input Current at Any Pin (3) ±30 mA
Package Input Current (3) ±120 mA
Package Dissipation at TA= 25°C (4) 500 mW
ESD Susceptibility (5)
Human Body Model 1500V
Soldering Information
PDIP Packages (10 seconds) 260°C
SOIC Package (6)
Vapor Phase (60 seconds) 215°C
Infrared (15 seconds) 220°C
Storage Temperature 65°C to +150°C
(1) All voltages are measured with respect to GND, unless otherwise specified.
(2) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. For ensured specifications and test conditions, see the
Electrical Characteristics. The ensured specifications apply only for the test conditions listed. Some performance characteristics may
degrade when the device is not operated under the listed test conditions.
(3) When the input voltage (VIN) at any pin exceeds the power supplies (VIN < GND or VIN > VA+ or VD+), the current at that pin should be
limited to 30 mA. The 120 mA maximum package input current rating limits the number of pins that can safely exceed the power
supplies with an input current of 30 mA to four.
(4) The maximum power dissipation must be derated at elevated temperatures and is dictated by TJmax, θJA and the ambient temperature,
TA. The maximum allowable power dissipation at any temperature is PD= (TJmax TA)/θJA or the number given in the Absolute
Maximum Ratings, whichever is lower. For this device, TJmax = 150°C.
(5) The human body model is a 100 pF capacitor discharged through a 1.5 kΩresistor into each pin.
(6) See AN450 “Surface Mounting Methods and Their Effect on Product Reliability” or the section titled “Surface Mount” found in any post
1986 Texas Instruments Linear Data Book for other methods of soldering surface mount devices.
Operating Ratings (1)(2)
Operating Temperature Range TMIN TATMAX
40°C TA+85°C
Supply Voltage (V+= VA+=VD+) +3.0V to +5.5V
|VA+VD+| 100 mV
VREF+ 0V to VA+
VREF0V to (VREF+1V)
VREF (VREF+VREF) 1V to VA+
VREF Common Mode Voltage Range
[(VREF+) (VREF)] / 2 0.1 VA+ to 0.6 VA+
A/DIN1, A/DIN2, MUXOUT1
and MUXOUT2 Voltage Range 0V to VA+
ADC IN Common Mode Voltage Range
[(VIN+) (VIN)] / 2 0V to VA+
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is functional, but do not ensure specific performance limits. For ensured specifications and test conditions, see the
Electrical Characteristics. The ensured specifications apply only for the test conditions listed. Some performance characteristics may
degrade when the device is not operated under the listed test conditions.
(2) All voltages are measured with respect to GND, unless otherwise specified.
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Package Thermal Resistance
Part Number Thermal Resistance (θJA)
ADC12130CIN 53°C/W
ADC12130CIWM 70°C/W
ADC12132CIMSA 134°C/W
ADC12132CIWM 64°C/W
ADC121038CIN 40°C/W
ADC121038CIMSA 97°C/W
ADC12138CIWM 50°C/W
Some of these product/package combinations are obsolete and are shown here for reference only. Check the TI
web site for availability.
Converter Electrical Characteristics
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = 3.3V, VREF+ = 2.5V and fully-differential input with fixed 1.250V common-mode
voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω, fCK = fSK
= 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;all other
limits TA= TJ= 25°C. (2)(3)(4)
Units
Parameter Test Conditions Typical (5) Limits (6) (Limits)
STATIC CONVERTER CHARACTERISTICS
Resolution with No Missing Codes 12 + sign Bits (min)
ILE Integral Linearity Error After Auto Cal (7) (8) ±1/2 ±2 LSB (max)
DNL Differential Non-Linearity After Auto Cal ±1.5 LSB (max)
Positive Full-Scale Error After Auto Cal (7) (8) ±1/2 ±3.0 LSB (max)
Negative Full-Scale Error After Auto Cal (7)(8) ±1/2 ±3.0 LSB (max)
After Auto Cal (9)(8)
Offset Error ±1/2 ±2 LSB (max)
VIN(+) = VIN() = 2.048V
(1) The “12-Bit Conversion of Offset” and “12-Bit Conversion of Full-Scale” modes are intended to test the functionality of the device.
Therefore, the output data from these modes are not an indication of the accuracy of a conversion result.
(2) Two on-chip diodes are tied to each analog input through a series resistor as shown below. Input voltage magnitude up to 5V above VA+
or 5V below GND will not damage this device. However, errors in conversion can occur (if these diodes are forward biased by more than
50 mV) if the input voltage magnitude of selected or unselected analog input go above VA+ or below GND by more than 50 mV. As an
example, if VA+ is 4.5 VDC, full-scale input voltage must be 4.55 VDC to ensure accurate conversions.
(3) To ensure accuracy, it is required that the VA+ and VD+ be connected together to the same power supply with separate bypass
capacitors at each V+pin.
(4) With the test condition for VREF (VREF+VREF) given as +4.096V, the 12-bit LSB is 1.0 mV. For VREF = 2.5V, the 12-bit LSB is 610 μV.
(5) Typical figures are at TJ= TA= 25°C and represent most likely parametric norm.
(6) Tested limits are specified to TI's AOQL (Average Outgoing Quality Level).
(7) Positive integral linearity error is defined as the deviation of the analog value, expressed in LSBs, from the straight line that passes
through positive full-scale and zero. For negative integral linearity error, the straight line passes through negative full-scale and zero
(see Figure 5 and Figure 6).
(8) The ADC12130 family's self-calibration technique ensures linearity and offset errors as specified, but noise inherent in the self-
calibration process will result in a maximum repeatability uncertainty of 0.2 LSB.
(9) The human body model is a 100 pF capacitor discharged through a 1.5 kΩresistor into each pin.
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Converter Electrical Characteristics (continued)
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = 3.3V, VREF+ = 2.5V and fully-differential input with fixed 1.250V common-mode
voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω, fCK = fSK
= 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;all other
limits TA= TJ= 25°C. (2)(3)(4)
Units
Parameter Test Conditions Typical (5) Limits (6) (Limits)
DC Common Mode Error After Auto Cal (10) ±2 LSB (max)
TUE Total Unadjusted Error After Auto Cal (7)(11) (12) ±1 LSB
Multiplexer Chan-to-Chan Matching V+= +5V ±10%, VREF = +4.096V ±0.05 LSB
Power Supply Sensitivity Offset Error ±0.5 LSB
+ Full-Scale Error ±0.5 LSB
Full-Scale Error ±0.5 LSB
Integral Linearity Error ±0.5 LSB
UNIPOLAR DYNAMIC CONVERTER CHARACTERISTICS
fIN = 1 kHz, VIN = 5 VPP, VREF+= 5.0V 69.4 dB
S/(N+D) Signal-to-Noise Plus Distortion Ratio fIN = 20 kHz, VIN = 5 VPP, VREF+= 5.0V 68.3 dB
fIN = 40 kHz, VIN = 5 VPP, VREF+ = 5.0V 65.7 dB
3 dB Full Power Bandwidth VIN = 5 VPP, where S/(N+D) drops 3 dB 31 kHz
DIFFERENTIAL DYNAMIC CONVERTER CHARACTERISTICS
fIN = 1 kHz, VIN = ±5V, VREF+= 5.0V 77.0 dB
S/(N+D) Signal-to-Noise Plus Distortion Ratio fIN = 20 kHz, VIN = ±5V, VREF+= 5.0V 73.9 dB
fIN = 40 kHz, VIN = ±5V, VREF+= 5.0V 67.0 dB
3 dB Full Power Bandwidth VIN = ±5V, where S/(N+D) drops 3 dB 40 kHz
REFERENCE INPUT, ANALOG INPUTS AND MULTIPLEXER CHARACTERISTICS
CREF Reference Input Capacitance 85 pF
A/DIN1 and A/DIN2 Analog Input
CA/D 75 pF
Capacitance
A/DIN1 and A/DIN2 Analog Input VIN = +5.0V or VIN = 0V ±0.1 μA
Leakage Current
GND 0.05 V (min)
CH0–CH7 and COM Input Voltage (VA+) + 0.05 V (max)
CCH CH0–CH7 and COM Input Capacitance 10 pF
CMUXOUT MUX Output Capacitance 20 pF
On Channel = 5V and 0.01 μA
Off Channel = 0V
Off Channel Leakage (13)
CH0–CH7 and COM Pins On Channel = 0V and 0.01 μA
Off Channel = 5V
On Channel = 5V and 0.01 μA
Off Channel = 0V
On Channel Leakage (13)
CH0–CH7 and COM Pins On Channel = 0V and 0.01 μA
Off Channel = 5V
MUXOUT1 and MUXOUT2 Leakage VMUXOUT = 5.0V or VMUXOUT = 0V 0.01 μA
Current VIN = 2.5V and
RON MUX On Resistance 850 1900 Ω(max)
VMUXOUT = 2.4V
VIN = 2.5V and
RON Matching Channel to Channel 5 %
VMUXOUT = 2.4V
(10) The DC common-mode error is measured in the differential multiplexer mode with the assigned positive and negative input channels
shorted together.
(11) Offset or Zero error is a measure of the deviation from the mid-scale voltage (a code of zero), expressed in LSB. It is the average value
of the code transitions between 1 to 0 and 0 to +1 (see Figure 7).
(12) Total unadjusted error includes offset, full-scale, linearity and multiplexer errors.
(13) Channel leakage current is measured after the channel selection.
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Converter Electrical Characteristics (continued)
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = 3.3V, VREF+ = 2.5V and fully-differential input with fixed 1.250V common-mode
voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω, fCK = fSK
= 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;all other
limits TA= TJ= 25°C. (2)(3)(4)
Units
Parameter Test Conditions Typical (5) Limits (6) (Limits)
Channel-to-Channel Crosstalk VIN = 5 VPP, fIN = 40 kHz 72 dB
MUX Bandwidth 90 kHz
DC and Logic Electrical Characteristics
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully-differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = +3.3V, VREF+ = +2.5V and fully-differential input with fixed 1.250V common-
mode voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω,
fCK = fSK = 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;
all other limits TA= TJ= 25°C. (2)(3)(4)
V+= VA+ = V+= VA+ =
Typical Units
Parameter Test Conditions VD+ = 3.3V VD+ = 5V
(5) (Limits)
Limits (6) Limits (6)
CCLK, CS, CONV, DI, PD AND SCLK INPUT CHARACTERISTICS
VIN(1) Logical “1” Input Voltage VA+=VD+=V++10% 2.0 2.0 V (min)
VIN(0) Logical “0” Input Voltage VA+=VD+=V+10% 0.8 0.8 V (max)
IIN(1) Logical “1” Input Current VIN = V+0.005 1.0 1.0 μA (max)
IIN(0) Logical `“0” Input Current VIN = 0V 0.005 1.0 1.0 μA (min)
DO, EOC AND DOR DIGITAL OUTPUT CHARACTERISTICS
VA+=VD+=V+10%, 2.4 2.4 V (min)
IOUT =360 μA
VOUT(1) Logical “1” Output Voltage VA+=VD+=V+10%, 2.9 4.25 V (min)
IOUT =10 μA
VA+=VD+=V+10%
VOUT(0) Logical “0” Output Voltage 0.4 0.4 V (max)
IOUT = 1.6 mA
VOUT = 0V 0.1 3.0 3.0 μA (max)
IOUT TRI-STATE Output Current VOUT = V+0.1 3.0 3.0 μA (max)
+ISC Output Short Circuit Source Current VOUT = 0V 14 mA
ISC Output Short Circuit Sink Current VOUT = VD+ 16 mA
(1) The “12-Bit Conversion of Offset” and “12-Bit Conversion of Full-Scale” modes are intended to test the functionality of the device.
Therefore, the output data from these modes are not an indication of the accuracy of a conversion result.
(2) Two on-chip diodes are tied to each analog input through a series resistor as shown below. Input voltage magnitude up to 5V above VA+
or 5V below GND will not damage this device. However, errors in conversion can occur (if these diodes are forward biased by more than
50 mV) if the input voltage magnitude of selected or unselected analog input go above VA+ or below GND by more than 50 mV. As an
example, if VA+ is 4.5 VDC, full-scale input voltage must be 4.55 VDC to ensure accurate conversions.
(3) To ensure accuracy, it is required that the VA+ and VD+ be connected together to the same power supply with separate bypass
capacitors at each V+pin.
(4) With the test condition for VREF (VREF+VREF) given as +4.096V, the 12-bit LSB is 1.0 mV. For VREF = 2.5V, the 12-bit LSB is 610 μV.
(5) Typical figures are at TJ= TA= 25°C and represent most likely parametric norm.
(6) Tested limits are specified to TI's AOQL (Average Outgoing Quality Level).
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DC and Logic Electrical Characteristics (continued)
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully-differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = +3.3V, VREF+ = +2.5V and fully-differential input with fixed 1.250V common-
mode voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω,
fCK = fSK = 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;
all other limits TA= TJ= 25°C. (2)(3)(4)
V+= VA+ = V+= VA+ =
Typical Units
Parameter Test Conditions VD+ = 3.3V VD+ = 5V
(5) (Limits)
Limits (6) Limits (6)
POWER SUPPLY CHARACTERISTICS
Awake (Active) 1.5 2.5 mA (max)
CS = HIGH, Powered Down, 600 μA
ID+ Digital Supply Current CCLK on
CS = HIGH, Powered Down, 20 μA
CCLK off
Awake (Active) 3.0 4.0 mA (max)
CS = HIGH, Powered Down, 10 μA
IA+ Positive Analog Supply Current CCLK on
CS = HIGH, Powered Down, 0.1 μA
CCLK off
CS = HIGH, Powered Down, 70 μA
CCLK on
IREF Reference Input Current CS = HIGH, Powered Down, 0.1 μA
CCLK off
AC Electrical Characteristics
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully-differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = +3.3V, VREF+ = +2.5V and fully-differential input with fixed 1.250V common-
mode voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω,
fCK = fSK = 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;
all other limits TA= TJ= 25°C. (2)
Parameter Test Conditions Typical (3) Limits (4) Units (Limits)
10 5MHz (max)
fCK Conversion Clock (CCLK) Frequency 1 MHz (min)
10 5MHz (max)
fSK Serial Data Clock SCLK Frequency 0 Hz (min)
40 % (min)
Conversion Clock Duty Cycle 60 % (max)
40 % (min)
Serial Data Clock Duty Cycle 60 % (max)
44(tCK)44(tCK)(max)
tCConversion Time 12-Bit + Sign or 12-Bit 8.8 μs (max)
(1) The “12-Bit Conversion of Offset” and “12-Bit Conversion of Full-Scale” modes are intended to test the functionality of the device.
Therefore, the output data from these modes are not an indication of the accuracy of a conversion result.
(2) Timing specifications are tested at the TTL logic levels, VOL = 0.4V for a falling edge and VOL = 2.4V for a rising edge. TRI-STATE
output voltage is forced to 1.4V.
(3) Typical figures are at TJ= TA= 25°C and represent most likely parametric norm.
(4) Tested limits are specified to TI's AOQL (Average Outgoing Quality Level).
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AC Electrical Characteristics (continued)
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully-differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = +3.3V, VREF+ = +2.5V and fully-differential input with fixed 1.250V common-
mode voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω,
fCK = fSK = 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;
all other limits TA= TJ= 25°C. (2)
Parameter Test Conditions Typical (3) Limits (4) Units (Limits)
6(tCK)6(tCK)(min)
7(tCK)(max)
6 Cycles Programmed 1.2 μs (min)
1.4 μs (max)
10(tCK)10(tCK)(min)
11(tCK)(max)
10 Cycles Programmed 2.0 μs (min)
2.2 μs (max)
tAAcquisition Time (5) 18(tCK)18(tCK)(min)
19(tCK)(max)
18 Cycles Programmed 3.6 μs (min)
3.8 μs (max)
34(tCK)34(tCK)(min)
35(tCK)(max)
34 Cycles Programmed 6.8 μs (min)
7.0 μs (max)
4944(tCK)4944(tCK)(max)
tCAL Self-Calibration Time 988.8 μs (max)
76(tCK)76(tCK)(max)
tAZ Auto Zero Time 15.2 μs (max)
2(tCK)2(tCK)(min)
3(tCK)(max)
Self-Calibration or Auto Zero
tSYNC Synchronization Time from DOR 0.40 μs (min)
0.60 μs (max)
DOR High Time when CS is Low 9(tSK)9(tSK)(max)
tDOR Continuously for Read Data and Software 1.8 μs (max)
Power Up/Down 8(tSK)8(tSK)(max)
tCONV CONV Valid Data Time 1.6 μs (max)
(5) If SCLK and CCLK are driven from the same clock source, then tAis 6, 10, 18 or 34 clock periods minimum and maximum.
AC Electrical Characteristics
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully-differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = +3.3V, VREF+ = +2.5V and fully-differential input with fixed 1.250V common-
mode voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω,
fCK = fSK = 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;
all other limits TA= TJ= 25°C. (2) (Continued)
(1) The “12-Bit Conversion of Offset” and “12-Bit Conversion of Full-Scale” modes are intended to test the functionality of the device.
Therefore, the output data from these modes are not an indication of the accuracy of a conversion result.
(2) Timing specifications are tested at the TTL logic levels, VOL = 0.4V for a falling edge and VOL = 2.4V for a rising edge. TRI-STATE
output voltage is forced to 1.4V.
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AC Electrical Characteristics (continued)
The following specifications apply for (V+= VA+=VD+ = +5V, VREF+ = +4.096V, and fully-differential input with fixed 2.048V
common-mode voltage) or (V+= VA+=VD+ = +3.3V, VREF+ = +2.5V and fully-differential input with fixed 1.250V common-
mode voltage), VREF= 0V, 12-bit + sign conversion mode(1), source impedance for analog inputs, VREFand VREF+25Ω,
fCK = fSK = 5 MHz, and 10 (tCK) acquisition time unless otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;
all other limits TA= TJ= 25°C. (2) (Continued) Units
Parameter Test Conditions Typical (3) Limits (4) (Limits)
Hardware Power-Up Time, Time from PD
tHPU 500 700 μs (max)
Falling Edge to EOC Rising Edge
Software Power-Up Time, Time from Serial
tSPU 500 700 μs (max)
Data Clock Falling Edge to EOC Rising Edge
Access Time Delay from CS Falling Edge to
tACC 25 60 ns (max)
DO Data Valid
Set-Up Time of CS Falling Edge to Serial Data
tSET-UP 50 ns (min)
Clock Rising Edge
Delay from SCLK Falling Edge to CS Falling
tDELAY 05ns (min)
Edge
t1H, t0H Delay from CS Rising Edge to DO TRI-STATE RL= 3k, CL= 100 pF 70 100 ns (max)
DI Hold Time from Serial Data Clock Rising
tHDI 515 ns (max)
Edge
DI Set-Up Time from Serial Data Clock Rising
tSDI 510 ns (min)
Edge
DO Hold Time from Serial Data Clock Falling 35 65 ns (max)
tHDO RL= 3k, CL= 100 pF
Edge 5ns (min)
Delay from Serial Data Clock Falling Edge to
tDDO 50 90 ns (max)
DO Data Valid
DO Rise Time, TRI-STATE to High DO Rise 10 40 ns (max)
tRDO RL= 3k, CL= 100 pF
Time, Low to High 10 40 ns (max)
DO Fall Time, TRI-STATE to Low DO Fall 15 40 ns (max)
tFDO RL= 3k, CL= 100 pF
Time, High to Low 15 40 ns (max)
Delay from CS Falling Edge to DOR Falling
tCD 45 80 ns (max)
Edge
Delay from Serial Data Clock Falling Edge to
tSD 45 80 ns (max)
DOR Rising Edge
CIN Capacitance of Logic Inputs 20 pF
COUT Capacitance of Logic Outputs 20 pF
(3) Typical figures are at TJ= TA= 25°C and represent most likely parametric norm.
(4) Tested limits are specified to TI's AOQL (Average Outgoing Quality Level).
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Figure 4. Transfer Characteristic
Figure 5. Simplified Error Curve vs. Output Code without Auto Calibration or Auto Zero Cycles
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Figure 6. Simplified Error Curve vs. Output Code after Auto Calibration Cycle
Figure 7. Offset or Zero Error Voltage
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Typical Performance Characteristics
The following curves apply for 12-bit + sign mode after Auto Calibration unless otherwise specified.
Linearity Error Change Linearity Error Change
vs. Clock Frequency vs. Temperature
Figure 8. Figure 9.
Linearity Error Change Linearity Error Change
vs. Reference Voltage vs. Supply Voltage
Figure 10. Figure 11.
Full-Scale Error Change Full-Scale Error Change
vs. Clock Frequency vs. Temperature
Figure 12. Figure 13.
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Typical Performance Characteristics (continued)
The following curves apply for 12-bit + sign mode after Auto Calibration unless otherwise specified.
Full-Scale Error Change Full-Scale Error Change
vs. Reference Voltage vs. Supply Voltage
Figure 14. Figure 15.
Offset or Zero Error Change Offset or Zero Error Change
vs. Clock Frequency vs. Temperature
Figure 16. Figure 17.
Offset or Zero Error Change Offset or Zero Error Change
vs. Reference Voltage vs. Supply Voltage
Figure 18. Figure 19.
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Typical Performance Characteristics (continued)
The following curves apply for 12-bit + sign mode after Auto Calibration unless otherwise specified.
Analog Supply Current Digital Supply Current
vs. Temperature vs. Clock Frequency
Figure 20. Figure 21.
Digital Supply Current Linearity Error Change
vs. Temperature vs. Temperature
Figure 22. Figure 23.
Full-Scale Error Change Full-Scale Error Change
vs. Temperature vs. Supply Voltage
Figure 24. Figure 25.
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Typical Performance Characteristics (continued)
The following curves apply for 12-bit + sign mode after Auto Calibration unless otherwise specified.
Offset or Zero Error Change Offset or Zero Error Change
vs. Temperature vs. Supply Voltage
Figure 26. Figure 27.
Analog Supply Current Digital Supply Current
vs. Temperature vs. Temperature
Figure 28. Figure 29.
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Typical Dynamic Performance Characteristics
The following curves apply for 12-bit + sign mode after Auto Calibration unless otherwise specified.
Bipolar Spectral Response Bipolar Spectral Response
with 1 kHz Sine Wave Input with 10 kHz Sine Wave Input
Figure 30. Figure 31.
Bipolar Spectral Response Bipolar Spectral Response
with 20 kHz Sine Wave Input with 30 kHz Sine Wave Input
Figure 32. Figure 33.
Bipolar Spectral Response Bipolar Spectral Response
with 40 kHz Sine Wave Input with 50 kHz Sine Wave Input
Figure 34. Figure 35.
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Typical Dynamic Performance Characteristics (continued)
The following curves apply for 12-bit + sign mode after Auto Calibration unless otherwise specified.
Bipolar Spurious Free Unipolar Signal-to-Noise Ratio
Dynamic Range vs. Input Frequency
Figure 36. Figure 37.
Unipolar Signal-to-Noise Unipolar Signal-to-Noise
+ Distortion Ratio + Distortion Ratio
vs. Input Frequency vs. Input Signal Level
Figure 38. Figure 39.
Unipolar Spectral Response Unipolar Spectral Response
with 1 kHz Sine Wave Input with 10 kHz Sine Wave Input
Figure 40. Figure 41.
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Typical Dynamic Performance Characteristics (continued)
The following curves apply for 12-bit + sign mode after Auto Calibration unless otherwise specified.
Unipolar Spectral Response Unipolar Spectral Response
with 20 kHz Sine Wave Input with 30 kHz Sine Wave Input
Figure 42. Figure 43.
Unipolar Spectral Response Unipolar Spectral Response
with 40 kHz Sine Wave Input with 50 kHz Sine Wave Input
Figure 44. Figure 45.
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Test Circuits
Figure 46. DO “TRI-STATE” (t1H, t0H) Figure 47. DO except “TRI-STATE”
Figure 48. Leakage Current
Timing Diagrams
Figure 49. DO Falling and Rising Edge
Figure 50.
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SCLK
DO
tACC
tSD
tHDO tDDO
tHDO tDDO
2.4V2.4V 2.4V
0.4V
0.4V
tSET-UP
tCD
0 1 2 3 4 n
CS
DOR
EOC
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Figure 51. DI Data Input Timing
Figure 52. DO Data Output Timing Using CS
Figure 53. DO Data Output Timing with CS Continuously Low
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Note: DO output data is not valid during this cycle.
Figure 54. ADC12138 Auto Cal or Auto Zero
Figure 55. ADC12138 Read Data without Starting a Conversion Using CS
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Figure 56. ADC12138 Read Data without Starting a Conversion with CS Continuously Low
Figure 57. ADC12138 Conversion Using CS with 16-Bit Digital Output Format
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Figure 58. ADC12138 Conversion with CS Continuously Low and 16-Bit Digital Output Format
Figure 59. ADC12138 Software Power Up/Down Using CS with 16-Bit Digital Output Format
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Figure 60. ADC12138 Software Power Up/Down with CS Continuously Low and 16-Bit Digital Output
Format
Note: Hardware power up/down may occur at any time. If PD is high while a conversion is in progress that conversion
will be corrupted and erroneous data will be stored in the output shift register.
Figure 61. ADC12138 Hardware Power Up/Down
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ADC
VA+
+5.0V
VD+
VREF+
VREF-
+4.096V
DGNDAGND
ANALOG INPUT VOLTAGE
GROUND REFERENCE
ANALOG
INPUT
VOLTAGE
ASSIGNED
(+) INPUT
ANALOG
INPUT
VOLTAGE ASSIGNED
(-) INPUT
**
0.01 uF **
0.1 uF 10 uF *
**
0.01 uF **
0.1 uF 10 uF *
**
0.01 uF **
0.1 uF 10 uF *
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Figure 62. ADC12138 Configuration Modification—Example of a Status Read
*Tantalum
**Monolithic Ceramic or better
Figure 63. Recommended Power Supply Bypassing and Grounding
Figure 64. Protecting the MUXOUT1, MUXOUT2, A/DIN1 and A/DIN2 Analog Pins
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Format and Set-Up Tables
Table 1. Data Out Formats(1)
DB DB DB DB DB DB DB
DO Formats DB0 DB1 DB2 DB3 DB4 DB5 DB6 DB7 DB8 DB9 10 11 12 13 14 15 16
17 X X X X Sign MSB 10 9 8 7 6 5 4 3 2 1 LSB
Bits
MSB
First 13 Sing MSB 10 9 8 7 6 5 4 3 2 1 LSB
Bits
with
Sign 17 LSB 1 2 3 4 5 6 7 8 9 10 MSB Sign X X X X
Bits
LSB
First 13 LSB 1 2 3 4 5 6 7 8 9 10 MSB Sign
Bits
16 0000MSB10987654321LSB
Bits
MSB
First 12 MSB 10 9 8 7 6 5 4 3 2 1 LSB
with- Bits
out 16
Sign LSB12345678910MSB0000
Bits
LSB
First 12 LSB 1 2 3 4 5 6 7 8 9 10 MSB
Bits
(1) X = High or Low state.
Table 2. ADC12138 Multiplexer Addressing
Analog Channel Addressed and Assignment ADC Input Multiplexer Output
MUX Address with A/DIN1 tied to MUXOUT1 and A/DIN2 tied Polarity Channel Assignment
to MUXOUT2 Assignment Mode
CH CH CH CH CH CH CH CH
DI0 DI1 DI2 DI3 COM A/DIN1 A/DIN2 MUXOUT1 MUXOUT2
0 1 2 3 4 5 6 7
LLLL++CH0 CH1
L L L H + +CH2 CH3
L L H L + +CH4 CH5
L L H H + +CH6 CH7 Differential
L H L L ++ CH0 CH1
L H L H ++ CH2 CH3
L H H L ++ CH4 CH5
L H H H ++ CH6 CH7
H L L L + +CH0 COM
H L L H + +CH2 COM
H L H L + +CH4 COM
H L H H + +CH6 COM Single-Ended
H H L L + +CH1 COM
H H L H + +CH3 COM
H H H L + +CH5 COM
H H H H + +CH7 COM
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Table 3. ADC12130 and ADC12132 Multiplexer Addressing(1)
Analog Channel Addressed and Assignment ADC Input Polarity Multiplexer Output Channel
MUX Address with A/DIN1 tied to MUXOUT1 and A/DIN2 tied Assignment Assignment Mode
to MUXOUT2
DI0 DI1 CH0 CH1 COM A/DIN1 A/DIN2 MUXOUT1 MUXOUT2
L L + +CH0 CH1 Differential
L H ++ CH0 CH1
H L + +CH0 COM Single-Ended
H H + +CH1 COM
(1) ADC12130 do not have A/DIN1, A/DIN2, MUXOUT1 and MUXOUT2 pins.
Table 4. Mode Programming(1)
ADC12138 DI0 DI1 DI2 DI3 DI4 DI5 DI6 DI7 DO Format
Mode Selected
ADC12130 (next Conversion
(Current)
and DI0 DI1 DI2 DI3 DI4 DI5 Cycle)
ADC12132
See Table 2 or Table 3 L L L L 12 Bit Conversion 12 or 13 Bit MSB First
See Table 2 or Table 3 L L L H 12 Bit Conversion 16 or 17 Bit MSB First
See Table 2 or Table 3 L H L L 12 Bit Conversion 12 or 13 Bit LSB First
See Table 2 or Table 3 L H L H 12 Bit Conversion 16 or 17 Bit LSB First
L L L L H L L L Auto Cal No Change
L L L L H L L H Auto Zero No Change
L L L L H L H L Power Up No Change
L L L L H L H H Power Down No Change
L L L L H H L L Read Status Register No Change
L L L L H H L H Data Out without Sign No Change
H L L L H H L H Data Out with Sign No Change
L L L L H H H L Acquisition Time—6 CCLK Cycles No Change
L H L L H H H L Acquisition Time—10 CCLK Cycles No Change
H L L L H H H L Acquisition Time—18 CCLK Cycles No Change
H H L L H H H L Acquisition Time—34 CCLK Cycles No Change
L L L L H H H H User Mode No Change
Test Mode
H X X X H H H H No Change
(CH1–CH7 become Active Outputs)
(1) The ADC powers up with no Auto Cal, no Auto Zero, 10 CCLK acquisition time, 12-bit + sign conversion, power up, 12- or 13-bit MSB
First, and user mode.
X = Don't Care
Table 5. Conversion/Read Data Only Mode Programming(1)
CS CONV PD Mode
L L L See Table 4 for Mode
L H L Read Only (Previous DO Format). No Conversion.
H X L Idle
X X H Power Down
(1) X = Don't Care
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Table 6. Status Register
Status Bit DB0 DB1 DB2 DB3 DB4 DB5 DB6 DB7 DB8
Location
Status Bit PU PD Cal 12 or 13 16 or 17 Sign Justification Test Mode
Device Status DO Output Format Status
Function “High” “High” “High” Not used “High” “High” “High” When “High When
indicates a indicates a indicates an indicates a indicates a indicates the conversion “High” the
Power Up Power Auto Cal 12 or 13 bit 16 or 17 bit that the result will be device is in
Sequence Down Sequence format format sign bit is output MSB test mode.
is in Sequence is in included. first. When When
progress is in progress When “Low” the “Low” the
progress “Low” the result will be device is in
sign bit is output LSB user mode.
not first.
included.
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APPLICATION INFORMATION
NOTE: Some of the device/package combinations are obsolete and are shown and described here for
reference only. Please see the TI web site for availability.
1.0 DIGITAL INTERFACE
1.1 Interface Concepts
The example in Figure 65 shows a typical sequence of events after the power is applied to the ADC12130/2/8:
Figure 65. Typical Power Supply Power Up Sequence
The first instruction input to the ADC via DI initiates Auto Cal. The data output on DO at that time is meaningless
and is completely random. To determine whether the Auto Cal has been completed, a read status instruction
should be issued to the ADC. Again the data output at that time has no significance since the Auto Cal procedure
modifies the data in the output shift register. To retrieve the status information, an additional read status
instruction should be issued to the ADC. At this time the status data is available on DO. If the Cal signal in the
status word is low, Auto Cal has been completed. Therefore, the next instruction issued can start a conversion.
The data output at this time is again status information.
To keep noise from corrupting the conversion, status can not be read during a conversion. If CS is strobed and is
brought low during a conversion, that conversion is prematurely ended. EOC can be used to determine the end
of a conversion or the ADC controller can keep track in software of when it would be appropriate to communicate
to the ADC again. Once it has been determined that the ADC has completed a conversion, another instruction
can be transmitted to the ADC. The data from this conversion can be accessed when the next instruction is
issued to the ADC.
Note, when CS is low continuously it is important to transmit the exact number of SCLK cycles, as shown in the
timing diagrams. Not doing so will desynchronize the serial communication to the ADC. (See 1.3 CS Low
Continuously Considerations.)
1.2 Changing Configuration
The configuration of the ADC12130/2/8 on power up defaults to 12-bit plus sign resolution, 12- or 13-bit MSB
First, 10 CCLK acquisition time, user mode, no Auto Cal, no Auto Zero, and power up mode. Changing the
acquisition time and turning the sign bit on and off requires an 8-bit instruction to be issued to the ADC. This
instruction will not start a conversion. The instructions that select a multiplexer address and format the output
data do start a conversion. Figure 66 describes an example of changing the configuration of the ADC12130/2/8.
During I/O sequence 1, the instruction at DI configures the ADC to do a conversion with 12-bit +sign resolution.
Notice that, when the 6 CCLK Acquisition and Data Out without Sign instructions are issued to the ADC, I/O
sequences 2 and 3, a new conversion is not started. The data output during these instructions is from conversion
N, which was started during I/O sequence 1. The Figure 62 describes in detail the sequence of events necessary
for a Data Out without Sign, Data Out with Sign, or 6/10/18/34 CCLK Acquisition time mode selection. Table 4
describes the actual data necessary to be loaded into the ADC to accomplish this configuration modification. The
next instruction, shown in Figure 66, issued to the ADC starts conversion N+1 with 16-bit format and 12 bits of
resolution formatted MSB first. Again the data output during this I/O cycle is the data from conversion N.
The number of SCLKs applied to the ADC during any conversion I/O sequence should vary in accord with the
data out word format chosen during the previous conversion I/O sequence. The various formats and resolutions
available are shown in Table 1.InFigure 66, since 16-bit without sign MSB first format was chosen during I/O
sequence 4, the number of SCLKs required during I/O sequence 5 is sixteen. In the following I/O sequence the
format changes to 12-bit without sign MSB first; therefore the number of SCLKs required during I/O sequence 6
changes accordingly to 12.
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1.3 CS Low Continuously Considerations
When CS is continuously low, it is important to transmit the exact number of SCLK pulses that the ADC expects.
Not doing so will desynchronize the serial communications to the ADC. When the supply power is first applied to
the ADC, it will expect to see 13 SCLK pulses for each I/O transmission. The number of SCLK pulses that the
ADC expects to see is the same as the digital output word length. The digital output word length is controlled by
the Data Out (DO) format. The DO format maybe changed any time a conversion is started or when the sign bit
is turned on or off. The table below details out the number of clock periods required for different DO formats:
DO Format Number of SCLKs Expected
SIGN OFF 12
12-Bit MSB or LSB First SIGN ON 13
SIGN OFF 16
16-Bit MSB or LSB first SIGN ON 17
If erroneous SCLK pulses desynchronize the communications, the simplest way to recover is by cycling the
power supply to the device. Not being able to easily resynchronize the device is a shortcoming of leaving CS low
continuously.
The number of clock pulses required for an I/O exchange may be different for the case when CS is left low
continuously vs. the case when CS is cycled. Take the I/O sequence detailed in Figure 65 as an example. The
table below lists the number of SCLK pulses required for each instruction:
Instruction CS Low Continuously CS Strobed
Auto Cal 13 SCLKs 8 SCLKs
Read Status 13 SCLKs 8 SCLKs
Read Status 13 SCLKs 8 SCLKs
12-Bit + Sign Conv 1 13 SCLKs 8 SCLKs
12-Bit + Sign Conv 2 13 SCLKs 13 SCLKs
1.4 Analog Input Channel Selection
The data input at DI also selects the channel configuration (see Table 2,Table 3, and Table 4). In Figure 66 the
only times when the channel configuration could be modified would be during I/O sequences 1, 4, 5 and 6. Input
channels are reselected before the start of each new conversion. Shown below is the data bit stream required at
DI during I/O sequence number 4 in Figure 66 to set CH1 as the positive input and CH0 as the negative input for
the different ADC versions.
Part DI Data(1)
Number DI0 DI1 DI2 DI3 DI4 DI5 DI6 DI7
ADC12130andADC12132 L H L L H L X X
ADC12138 L H L L L L H L
(1) X can be a logic high (H) or low (L).
1.5 Power Up/Down
The ADC may be powered down by taking the PD pin HIGH or by the instruction input at DI (see Table 4,
Table 5,Figure 59,Figure 60, and Figure 61). When the ADC is powered down in this way, the ADC conversion
circuitry is deactivated but the digital I/O circuitry is kept active.
Hardware power up/down is controlled by the state of the PD pin. Software power-up/down is controlled by the
instruction issued to the ADC. If a software power up instruction is issued to the ADC while a hardware power
down is in effect (PD pin high) the device will remain in the power-down state. If a software power down
instruction is issued to the ADC while a hardware power up is in effect (PD pin low), the device will power down.
When the device is powered down by software, it may be powered up by either issuing a software power up
instruction or by taking PD pin high and then low. If the power down command is issued during a conversion, that
conversion is interrupted, so the data output after power up cannot be relied upon.
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Figure 66. Changing the ADC's Conversion Configuration
1.6 User Mode and Test Mode
An instruction may be issued to the ADC to put it into test mode, which is used by the manufacturer to verify
complete functionality of the device. During test mode CH0–CH7 become active outputs. If the device is
inadvertently put into the test mode with CS continuously low, the serial communications may be
desynchronized. Synchronization may be regained by cycling the power supply voltage to the device. Cycling the
power supply voltage will also set the device into user mode. If CS is used in the serial interface, the ADC may
be queried to see what mode it is in. This is done by issuing a “read STATUS register” instruction to the ADC.
When bit 9 of the status register is high, the ADC is in test mode; when bit 9 is low the ADC, is in user mode. As
an alternative to cycling the power supply, an instruction sequence may be used to return the device to user
mode. This instruction sequence must be issued to the ADC using CS. The following table lists the instructions
required to return the device to user mode. Note that this entire sequence, including both Test Mode and User
Mode values, should be sent to recover from the test mode.
DI Data(1)
Instruction DI0 DI1 DI2 DI3 DI4 DI5 DI6 DI7
TEST MODE H X X X H H H H
Reset L L L L H H H L
Test Mode L L L L H L H L
Instructions L L L L H L H H
USER MODE L L L L H H H H
Power Up L L L L H L H L
Set DO with or without Sign H or L L L L H H L H
Set Acquisition Time H or L H or L L L H H H L
Start a Conversion H or L H or L H or L H or L L H or L H or L H or L
(1) X = Don't Care
The power up, data with or without sign, and acquisition time instructions should be resent after returning to the
user mode. This is to ensure that the ADC is in the required state before a conversion is started.
1.7 Reading the Data Without Starting a Conversion
The data from a particular conversion may be accessed without starting a new conversion by ensuring that the
CONV line is taken high during the I/O sequence. See Figure 55 and Figure 56.Table 5 describes the operation
of the CONV pin. It is not necessary to read the data as soon as DOR goes low. The data will remain in the
output register ifCS is brought high right after DOR goes high. A single conversion may be read as many times
as desired before CS is brought low.
1.8 Brown Out Conditions
When the supply voltage dips below about 2.7V, the internal registers, including the calibration coefficients and
all of the other registers, may lose their contents. When this happens the ADC will not perform as expected or
not at all after power is fully restored. While writing the desired information to all registers and performing a
calibration might sometimes cause recovery to full operation, the only sure recovery method is to reduce the
supply voltage to below 0.5V, then reprogram the ADC and perform a calibration after power is fully restored.
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2.0 THE ANALOG MULTIPLEXER
For the ADC12138, the analog input multiplexer can be configured with 4 differential channels or 8 single ended
channels with the COM input as the zero reference or any combination thereof (see Figure 67). The difference
between the voltages at the VREF+and VREFpins determines the input voltage span (VREF). The analog input
voltage range is 0 to VA+. Negative digital output codes result when VIN> VIN+. The actual voltage at VINor VIN+
cannot go below AGND. 8 Single-Ended Channels
4 Differential with COM
Channels as Zero Reference
Figure 67. Input Multiplexer Options
Differential Single-Ended
Configuration Configuration
A/DIN1 and A/DIN2 can be assigned as the + or input
A/DIN1 is + input
A/DIN2 is input
Figure 68. MUXOUT connections for multiplexer option
CH0, CH2, CH4, and CH6 can be assigned to the MUXOUT1 pin in the differential configuration, while CH1,
CH3, CH5, and CH7 can be assigned to the MUXOUT2 pin. In the differential configuration, the analog inputs
are paired as follows: CH0 with CH1, CH2 with CH3, CH4 with CH5 and CH6 with CH7. The A/DIN1 and A/DIN2
pins can be assigned positive or negative polarity.
With the single-ended multiplexer configuration, CH0 through CH7 can be assigned to the MUXOUT1 pin. The
COM pin is always assigned to the MUXOUT2 pin. A/DIN1 is assigned as the positive input; A/DIN2 is assigned
as the negative input. (See Figure 68).
The Multiplexer assignment tables for these ADCs (Table 2 and Table 3) summarize the aforementioned
functions for the different versions of ADCs.
2.1 Biasing for Various Multiplexer Configurations
Figure 69 is an example of device connections for single-ended operation. The sign bit is always low. The digital
output range is 0 0000 0000 0000 to 0 1111 1111 1111. One LSB is equal to 1 mV (4.1V/4096 LSBs).
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ADC1213X
VA+
LM4040-2.5
(LM4041-1.2)
430:
+5.0V
(+3.3V)
VD+
VREF+
VREF-
+2.5V
(+1.25V)
DGNDAGND
ANALOG INPUT VOLTAGE
GROUND REFERENCE
CH0
CH1
CH2
to
CH7
COM
ANALOG INPUT
VOLTAGE RANGE
0V to 5V
(0V to 2.5V)
12-BITS SIGNED ASSIGNED
(+) INPUT
ASSIGNED
(-) INPUT
R2
600:R1
(DEPENDS UPON
ACQUISITION TIME)
0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
ADC1213X
VA+0.01 uF 0.1 uF 10 uF
LM4040-4.1
(LM4040-2.5)
1k
+5.0V
(+3.3V)
VD+
VREF+
VREF-
+2.048V
(+2.5)
DGNDAGND
ANALOG INPUT VOLTAGE
GROUND REFERENCE
CH0
CH1
CH2
to
CH7
COM
ASSIGNED
(+) INPUT
ASSIGNED
(-) INPUT
ANALOG INPUT
VOLTAGE RANGE
0 TO 4.096V
(0V TO 2.5V)
12-BITS UNSIGNED 0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
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Figure 69. Single-Ended Biasing
For pseudo-differential signed operation, the circuit of Figure 70 shows a signal AC coupled to the ADC. This
gives a digital output range of 4096 to +4095. With a 2.5V reference, 1 LSB is equal to 610 μV. Although the
ADC is not production tested with a 2.5V reference, when VA+and VD+are +5.0V, linearity error typically will not
change more than 0.1 LSB (see the curves in Typical Performance Characteristics). With the ADC set to an
acquisition time of 10 clock periods, the input biasing resistor needs to be 600Ωor less. Notice though that the
input coupling capacitor needs to be made fairly large to bring down the high pass corner. Increasing the
acquisition time to 34 clock periods (with a 5 MHz CCLK frequency) would allow the 600Ωto increase to 6k,
which would set the high pass corner at 26 Hz. Increasing R, to 6k would allow R2to be 2k with a 1 μF coupling
capacitor.
Figure 70. Pseudo-Differential Biasing with the Signal Source AC Coupled Directly into the ADC
An alternative method for biasing pseudo-differential operation is to use the +2.5V from the LM4040 to bias any
amplifier circuits driving the ADC as shown in Figure 71. The value of the resistor pull-up biasing the LM4040-2.5
will depend upon the current required by the op amp biasing circuitry.
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VA+
LM4041-ADJ
2k
+5.0V
VD+
VREF+
VREF-
+2.048V
DGNDAGND
ANALOG INPUT VOLTAGE
GROUND REFERENCE
CH0
CH1
CH2
to
CH7
COM
ASSIGNED
(+) INPUT
ASSIGNED
(-) INPUT
+5.0V
+
-
ANALOG
INPUT
VOLTAGE
ANALOG INPUT
VOLTAGE RANGE
2.5V +/- 2.048V
12-BITS SIGNED
LM4040-2.5
1M 1k
0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
ADC1213X
VA+
LM4040-2.5
(LM4041-1.2)
1k
+5.0V
(+3.3V)
VD+
VREF+
VREF-
+2.5V
(+1.25V)
DGNDAGND
ANALOG INPUT VOLTAGE
GROUND REFERENCE
CH0
CH1
CH2
to
CH7
COM
ASSIGNED
(+) INPUT
ASSIGNED
(-) INPUT
1M
+
-
ANALOG
INPUT
VOLTAGE
ANALOG INPUT
VOLTAGE RANGE
0V to 5V
(0V to 2.5V)
12-BITS SIGNED
0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
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In the circuit of Figure 71, some voltage range is lost since the amplifier will not be able to swing to +5V and
GND with a single +5V supply. Using an adjustable version of the LM4041 to set the full scale voltage at exactly
2.048V and a lower grade LM4040D-2.5 to bias up everything to 2.5V as shown in Figure 72 will allow the use of
all the ADC's digital output range of 4096 to +4095 while leaving plenty of head room for the amplifier.
Fully differential operation is shown in Figure 73. One LSB for this case is equal to (4.1V/4096) = 1 mV.
Figure 71. Alternative Pseudo-Differential Biasing
Figure 72. Pseudo-Differential Biasing without the Loss of Digital Output Range
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VA+
LM4040-4.1
(LM4040-2.5)
1k
+5.0V
(+3.3V)
VD+
VREF+
VREF-
+4.1V
(+2.5V)
DGNDAGND
ANALOG INPUT VOLTAGE
GROUND REFERENCE
CH0
CH2
CH4
or
CH6
CH1
CH3
CH4
or
CH7
ANALOG INPUT VOLTAGE RANGE
0.45V to 4.55V
(0.4V to 2.9V) ASSIGNED
(+) INPUT
ANALOG INPUT VOLTAGE RANGE
0.45V to 4.55V
(0.4V to 2.9V) ASSIGNED
(-) INPUT
FULLY DIFFERENTIAL
12-BIT PLUS SIGN
0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
0.01 uF 0.1 uF 10 uF
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Figure 73. Fully Differential Biasing
3.0 REFERENCE VOLTAGE
The difference in the voltages applied to the VREF+and VREFdefines the analog input span (the difference
between the voltage applied between two multiplexer inputs or the voltage applied to one of the multiplexer
inputs and analog ground) over which 4095 positive and 4096 negative codes exist. The voltage sources driving
VREF+and VREFmust have very low output impedance and noise. The circuit in Figure 74 is an example of a
very stable reference appropriate for use with the device.
*Tantalum
Figure 74. Low Drift Extremely
Stable Reference Circuit
The ADC12130/2/8 can be used in either ratiometric or absolute reference applications. In ratiometric systems,
the analog input voltage is proportional to the voltage used for the ADC's reference voltage. When this voltage is
the system power supply, the VREF+pin is connected to VA+and VREFis connected to ground. This technique
relaxes the system reference stability requirements because the analog input voltage and the ADC reference
voltage move together. This maintains the same output code for given input conditions. For absolute accuracy,
where the analog input voltage varies between very specific voltage limits, a time and temperature stable voltage
source can be connected to the reference inputs. Typically, the reference voltage magnitude will require an initial
adjustment to null reference voltage induced full-scale errors.
Below are recommended references along with some key specifications.
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Part Number Output Voltage Tolerance Temperature Coefficient
LM4041CI-Adj ±0.5% ±100ppm/°C
LM4040AI-4.1 ±0.1% ±100ppm/°C
LM4120AI-4.1 ±0.2% ±50ppm/°C
LM4121AI-4.1 ±0.2% ±50ppm/°C
LM4050AI-4.1 ±0.1% ±50ppm/°C
LM4030AI-4.1 ±0.05% ±10ppm/°C
LM4040AI-4.1 ±0.1% ±3.0ppm/°C
Circuit of Figure 74 Adjustable ±2ppm/°C
The reference voltage inputs are not fully differential. The ADC12130/2/8 will not generate correct conversions or
comparisons if VREF+is taken below VREF. Correct conversions result when VREF+and VREFdiffer by 1V or more
and remain at all times between ground and VA+. The VREF common mode range, (VREF++ VREF)/2, is restricted
to (0.1 × VA+) to (0.6 × VA+). Therefore, with VA+= 5V, the center of the reference ladder should not go below
0.5V or above 3.0V. Figure 75 is a graphic representation of the voltage restrictions on VREF+and VREF.
Figure 75. VREF Operating Range
4.0 ANALOG INPUT VOLTAGE RANGE
The ADC12130/2/8's fully differential ADC generate a two's complement output that is found by using the
equation shown below:
for (12-bit) resolution the Output Code =
(1)
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Round off to the nearest integer value between 4096 to 4095 if the result of the above equation is not a whole
number.
Examples are shown in the table below:
VREF+VREFVIN+VINCode Output Digital
+2.5V +1V +1.5V 0V 0,1111,1111,1111
+4.096V 0V +3V 0V 0,1011,1011,1000
+4.096V 0V +2.499V +2.500V 1,1111,1111,1111
+4.096V 0V 0V +4.096V 1,0000,0000,0000
5.0 INPUT CURRENT
At the start of the acquisition window (tA) a charging current flows into or out of the analog input pins (A/DIN1 and
A/DIN2) depending upon the input voltage polarity. The analog input pins are CH0–CH7 and COM when A/DIN1
is tied to MUXOUT1 and A/DIN2 is tied to MUXOUT2. The peak value of this input current will depend upon the
actual input voltage applied, the source impedance and the internal multiplexer switch on resistance. With
MUXOUT1 tied to A/DIN1 and MUXOUT2 tied to A/DIN2 the internal multiplexer switch on resistance is typically
1.6 kΩ. The A/DIN1 and A/DIN2 mux on resistance is typically 750Ω.
6.0 INPUT SOURCE RESISTANCE
For low impedance voltage sources (<600Ω), the input charging current will decay, before the end of the S/H's
acquisition time of 2 μs (10 CCLK periods with fCK = 5 MHz), to a value that will not introduce any conversion
errors. For high source impedances, the S/H's acquisition time can be increased to 18 or 34 CCLK periods. For
less ADC accuracy and/or slower CCLK frequencies the S/H's acquisition time may be decreased to 6 CCLK
periods. To determine the number of clock periods (Nc) required for the acquisition time with a specific source
impedance for the various resolutions the following equations can be used:
12 Bit + Sign NC= [RS+ 2.3] × fCK × 0.824
Where fCK is the conversion clock (CCLK) frequency in MHz and RSis the external source resistance in kΩ. As
an example, operating with a resolution of 12 Bits + sign, a 5 MHz clock frequency and maximum acquisition
time of 34 conversion clock periods the ADC's analog inputs can handle a source impedance as high as 6 kΩ.
The acquisition time may also be extended to compensate for the settling or response time of external circuitry
connected between the MUXOUT and A/DIN pins.
An acquisition starts at a falling edge of SCLK and ends at a rising edge of CCLK (see timing diagrams). If SCLK
and CCLK are asynchronous, one extra CCLK clock period may be inserted into the programmed acquisition
time for synchronization. Therefore, with asynchronous SCLK and CCLK, the acquisition time will change from
conversion to conversion.
7.0 INPUT BYPASS CAPACITANCE
External capacitors (0.01 μF–0.1 μF) can be connected between the analog input pins, CH0–CH7, and analog
ground to filter any noise caused by inductive pickup associated with long input leads. These capacitors will not
degrade the conversion accuracy.
8.0 NOISE
The leads to each of the analog multiplexer input pins should be kept as short as possible. This will minimize
input noise and clock frequency coupling that can cause conversion errors. Input filtering can be used to reduce
the effects of the noise sources.
9.0 POWER SUPPLIES
Noise spikes on the VA+and VD+supply lines can cause conversion errors; the comparator will respond to the
noise. The ADC is especially sensitive to any power supply spikes that occur during the Auto Zero or linearity
correction. The minimum power supply bypassing capacitors recommended are low inductance tantalum
capacitors of 10 μF or greater paralleled with 0.1 μF monolithic ceramic capacitors. More or different bypassing
may be necessary depending upon the overall system requirements. Separate bypass capacitors should be used
for the VA+and VD+supplies and placed as close as possible to these pins.
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10.0 GROUNDING
The ADC12130/2/8's performance can be maximized through proper grounding techniques. These include the
use of separate analog and digital areas of the board with analog and digital components and traces located only
in their respective areas. Bypass capacitors of 0.01 µF and 0.1 µF surface mount capacitors and a 10 µF are
recommended at each of the power supply pins for best performance. These capacitors should be located as
close to the bypassed pin as practical, especially the smaller value capacitors.
11.0 CLOCK SIGNAL LINE ISOLATION
The ADC12130/2/8's performance is optimized by routing the analog input/output and reference signal
conductors as far as possible from the conductors that carry the clock signals to the CCLK and SCLK pins.
Maintaining a separation of at least 7 to 10 times the height of the clock trace above its reference plane is
recommended.
12.0 THE CALIBRATION CYCLE
A calibration cycle needs to be started after the power supplies, reference, and clock have been given enough
time to stabilize after initial turn-on. During the calibration cycle, correction values are determined for the offset
voltage of the sampled data comparator and any linearity and gain errors. These values are stored in internal
RAM and used during an analog-to-digital conversion to bring the overall full-scale, offset, and linearity errors
down to the specified limits. Full-scale error typically changes ±0.4 LSB over temperature and linearity error
changes even less; therefore, it should be necessary to go through the calibration cycle only once after power up
if the Power Supply Voltage and the ambient temperature do not change significantly (see the curves in the
Typical Performance Characteristics).
13.0 THE Auto Zero CYCLE
To correct for any change in the zero (offset) error of the ADC, the Auto Zero cycle can be used. It may be
desirable to do an Auto Zero cycle whenever the ambient temperature or the power supply voltage change
significantly. (See the curves, Figure 17 and Figure 19, in the Typical Performance Characteristics.)
14.0 DYNAMIC PERFORMANCE
Many applications require the converter to digitize AC signals, but the standard DC integral and differential
nonlinearity specifications will not accurately predict the converter's performance with AC input signals. The
important specifications for AC applications reflect the converter's ability to digitize AC signals without significant
spectral errors and without adding noise to the digitized signal. Dynamic characteristics such as signal-to-noise
(S/N), signal-to-noise + distortion ratio or S/(N + D), effective bits, full power bandwidth, aperture time and
aperture jitter are quantitative measures of the converter's capability.
An ADC's AC performance can be measured using Fast Fourier Transform (FFT) methods. A sinusoidal
waveform is applied to the ADC's input, and the transform is then performed on the digitized waveform. S/(N + D)
and S/N are calculated from the resulting FFT data, and a spectral plot may also be obtained. Typical values for
S/N are shown in Converter Electrical Characteristics, and spectral plots of S/(N + D) are included in Typical
Performance Characteristics.
The ADC's noise and distortion levels will change with the frequency of the input signal, with more distortion and
noise occurring at higher signal frequencies. This can be seen in the S/(N + D) versus frequency curves. These
curves will also give an indication of the full power bandwidth (the frequency at which the S/(N + D) or S/N drops
3 dB).
Effective number of bits can also be useful in describing the ADC's noise and distortion performance. An ideal
ADC will have some amount of quantization noise, determined by its resolution, and no distortion, which will yield
an optimum S/(N + D) ratio given by the following equation:
S/(N + D) = (6.02 × n + 1.76) dB
where
"n" is the ADC's resolution in bits (2)
The effective bits of an actual ADC can be found by:
n(effective) = ENOB = (S/(N + D) - 1.76) / 6.02 (3)
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ABC
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
COM
MUXOUT1
A/DIN1
MUXOUT2
A/DIN2
DGND
VD+
CCLK
SCLK
DI
DO
EOC
PD
AGND
VREF+
VREF-
VA+
DOR
CS
CONV RS-232
Interface
+4.096V
+5V
D Q
CLK
7474
1/6 74HC04 1/4 DS14C89
1/4 DS14C89
1/4 DS14C88
+5V
5 MHz
DTR
RTS
CTS
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As an example, this device with a differential signed 5V, 1 kHz sine wave input signal will typically have a S/(N +
D) of 77 dB, which is equivalent to 12.5 effective bits.
15.0 AN RS232 SERIAL INTERFACE
Shown on the following page is a schematic for an RS232 interface to any IBM and compatible PCs. The DTR,
RTS, and CTS RS232 signal lines are buffered via level translators and connected to the ADC12138's DI, SCLK,
and DO pins, respectively. The D flip-flop is used to generate the CS signal.
Note: VA+, VD+, and VREF+on the ADC12138 each have 0.01 μF and 0.1 μF chip caps, and 10 μF tantalum caps. All
logic devices are bypassed with 0.1 μF caps.
Figure 76. RS232 Serial Interface Schematic
The assignment of the RS232 port is shown below
B7 B6 B5 B4 B3 B2 B1 B0
Input Address 3FE X X X CTS X X X X
COM1 Output Address 3FC X X X 0 X X RTS DTR
A sample program, written in Microsoft QuickBasic, is shown on the next page. The program prompts for data
mode select instruction to be sent to the ADC. This can be found from the Mode Programming table shown
earlier. The data should be entered in “1”s and “0”s as shown in the table with DI0 first. Next, the program
prompts for the number of SCLK cycles required for the programmed mode select instruction. For instance, to
send all “0”s to the ADC, selects CH0 as the +input, CH1 as the input, 12-bit conversion, and 13-bit MSB first
data output format (if the sign bit was not turned off by a previous instruction). This would require 13 SCLK
periods since the output data format is 13 bits.
The ADC powers up with No Auto Cal, No Auto Zero, 10 CCLK Acquisition Time, 12-bit conversion, data out with
sign, power up, 12- or 13-bit MSB First, and user mode. Auto Cal, Auto Zero, Power Up and Power Down
instructions do not change these default settings. The following power up sequence should be followed:
1. Run the program
2. Prior to responding to the prompt apply the power to the ADC12138
3. Respond to the program prompts
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It is recommended that the first instruction issued to the ADC12138 be Auto Cal (See 1.1 Interface Concepts).
Code Listing:
'variables DOL=Data Out word length, DI=Data string for the DI input,
' DO=ADC result string
'SET CS# HIGH
OUT &H3FC, (&H2 OR INP (&H3FC) 'set RTS HIGH
OUT &H3FC, (&HFE AND INP(&H3FC) 'SET DTR LOW
OUT &H3FC, (&HFD AND INP (&H3FC) 'SET RTS LOW
OUT &H3FC, (&HEF AND INP(&H3FC)) 'set B4 low
10
LINE INPUT “DI data for ADC12138 (see Mode Table on data sheet)”; DI$
INPUT “ADC12138 output word length (12,13,16 or 17)”; DOL
20
'SET CS# HIGH
OUT &H3FC, (&H2 OR INP (&H3FC) 'set RTS HIGH
OUT &H3FC, (&HFE AND INP(&H3FC) 'SET DTR LOW
OUT &H3FC, (&HFD AND INP (&H3FC) 'SET RTS LOW
'SET CS# LOW
OUT &H3FC, (&H2 OR INP (&H3FC) 'set RTS HIGH
OUT &H3FC, (&H1 OR INP(&H3FC) 'SET DTR HIGH
OUT &H3FC, (&HFD AND INP (&H3FC) 'SET RTS LOW
DO$=“ 'reset DO variable
OUT &H3FC, (&H1 OR INP(&H3FC) 'SET DTR HIGH
OUT &H3FC, (&HFD AND INP(&H3FC)) 'SCLK low
FORN=1TO8
Temp$ = MID$(DI$, N, 1)
IF Temp$=“0” THEN
OUT &H3FC, (&H1 OR INP(&H3FC))
ELSE OUT &H3FC, (&HFE AND INP(&H3FC))
END IF 'out DI
OUT &H3FC, (&H2 OR INP(&H3FC)) 'SCLK high
IF (INP(&H3FE) AND 16) = 16 THEN
DO$ = DO$ + “0”
ELSE
DO$ = DO$ + “1”
END IF 'Input DO
OUT &H3FC, (&H1 OR INP(&H3FC) 'SET DTR HIGH
OUT &H3FC, (&HFD AND INP(&H3FC)) 'SCLK low
NEXT N
IF DOL > 8 THEN
FOR N=9 TO DOL
OUT &H3FC, (&H1 OR INP(&H3FC) 'SET DTR HIGH
OUT &H3FC, (&HFD AND INP(&H3FC)) 'SCLK low
OUT &H3FC, (&H2 OR INP(&H3FC)) 'SCLK high
IF (INP(&H3FE) AND &H1O) = &H1O THEN
DO$ = DO$ + “0”
ELSEDO$ = DO$ + “1”
END IF
NEXT N
END IF
OUT &H3FC, (&HFA AND INP(&H3FC)) 'SCLK low and DI high
FOR N = 1 TO 500
NEXT N
PRINT DO$
INPUT “Enter “C” to convert else “RETURN” to alter DI data”; s$
IF s$ = “C” OR s$ = “c” THEN
GOTO 20
ELSE
GOTO 10
END IF
END
42 Submit Documentation Feedback Copyright © 2000–2013, Texas Instruments Incorporated
Product Folder Links: ADC12130 ADC12132 ADC12138
ADC12130, ADC12132, ADC12138
www.ti.com
SNAS098G MARCH 2000REVISED MARCH 2013
REVISION HISTORY
Changes from Revision F (March 2013) to Revision G Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 42
Copyright © 2000–2013, Texas Instruments Incorporated Submit Documentation Feedback 43
Product Folder Links: ADC12130 ADC12132 ADC12138
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
ADC12130CIWMX/NOPB SOIC DW 16 1000 330.0 16.4 10.9 10.7 3.2 12.0 16.0 Q1
ADC12138CIMSAX/NOPB SSOP DB 28 2000 330.0 16.4 8.4 10.7 2.4 12.0 16.0 Q1
ADC12138CIWMX/NOPB SOIC DW 28 1000 330.0 24.4 10.8 18.4 3.2 12.0 24.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 23-Sep-2013
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
ADC12130CIWMX/NOPB SOIC DW 16 1000 367.0 367.0 38.0
ADC12138CIMSAX/NOPB SSOP DB 28 2000 367.0 367.0 38.0
ADC12138CIWMX/NOPB SOIC DW 28 1000 367.0 367.0 45.0
PACKAGE MATERIALS INFORMATION
www.ti.com 23-Sep-2013
Pack Materials-Page 2
GENERIC PACKAGE VIEW
Images above are just a representation of the package family, actual package may vary.
Refer to the product data sheet for package details.
DW 16 SOIC - 2.65 mm max height
SMALL OUTLINE INTEGRATED CIRCUIT
4040000-2/H
www.ti.com
PACKAGE OUTLINE
C
TYP
10.63
9.97
2.65 MAX
14X 1.27
16X 0.51
0.31
2X
8.89
TYP
0.33
0.10
0 - 8 0.3
0.1
(1.4)
0.25
GAGE PLANE
1.27
0.40
A
NOTE 3
10.5
10.1
BNOTE 4
7.6
7.4
4220721/A 07/2016
SOIC - 2.65 mm max heightDW0016A
SOIC
NOTES:
1. All linear dimensions are in millimeters. Dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed 0.15 mm, per side.
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm, per side.
5. Reference JEDEC registration MS-013.
116
0.25 C A B
9
8
PIN 1 ID
AREA
SEATING PLANE
0.1 C
SEE DETAIL A
DETAIL A
TYPICAL
SCALE 1.500
www.ti.com
EXAMPLE BOARD LAYOUT
0.07 MAX
ALL AROUND 0.07 MIN
ALL AROUND
(9.3)
14X (1.27)
R0.05 TYP
16X (2)
16X (0.6)
4220721/A 07/2016
SOIC - 2.65 mm max heightDW0016A
SOIC
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
METAL SOLDER MASK
OPENING
NON SOLDER MASK
DEFINED
SOLDER MASK DETAILS
OPENING
SOLDER MASK METAL
SOLDER MASK
DEFINED
LAND PATTERN EXAMPLE
SCALE:7X
SYMM
1
89
16
SEE
DETAILS
SYMM
www.ti.com
EXAMPLE STENCIL DESIGN
R0.05 TYP
16X (2)
16X (0.6)
14X (1.27)
(9.3)
4220721/A 07/2016
SOIC - 2.65 mm max heightDW0016A
SOIC
NOTES: (continued)
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
9. Board assembly site may have different recommendations for stencil design.
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE:7X
SYMM
SYMM
1
89
16
www.ti.com
PACKAGE OUTLINE
C
26X 0.65
2X
8.45
28X 0.38
0.22
8.2
7.4 TYP
SEATING
PLANE
0.05 MIN
0.25
GAGE PLANE
0 -8
2 MAX
B5.6
5.0
NOTE 4
A
10.5
9.9
NOTE 3
0.95
0.55
(0.15) TYP
SSOP - 2 mm max heightDB0028A
SMALL OUTLINE PACKAGE
4214853/B 03/2018
1
14 15
28
0.15 C A B
PIN 1 INDEX AREA
SEE DETAIL A
0.1 C
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed 0.15 mm per side.
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.
5. Reference JEDEC registration MO-150.
A 15
DETAIL A
TYPICAL
SCALE 1.500
www.ti.com
EXAMPLE BOARD LAYOUT
0.07 MAX
ALL AROUND 0.07 MIN
ALL AROUND
28X (1.85)
28X (0.45)
26X (0.65)
(7)
(R0.05) TYP
SSOP - 2 mm max heightDB0028A
SMALL OUTLINE PACKAGE
4214853/B 03/2018
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE: 10X
SYMM
SYMM
1
14 15
28
15.000
METAL
SOLDER MASK
OPENING METAL UNDER
SOLDER MASK SOLDER MASK
OPENING
EXPOSED METAL
EXPOSED METAL
SOLDER MASK DETAILS
NON-SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK
DEFINED
www.ti.com
EXAMPLE STENCIL DESIGN
28X (1.85)
28X (0.45)
26X (0.65)
(7)
(R0.05) TYP
SSOP - 2 mm max heightDB0028A
SMALL OUTLINE PACKAGE
4214853/B 03/2018
NOTES: (continued)
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
9. Board assembly site may have different recommendations for stencil design.
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE: 10X
SYMM
SYMM
1
14 15
28
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