General Description
The MAX3314E is a ±5V-powered EIA/TIA-232-compat-
ible interface. It has one transmitter and one receiver in
a flow-through architecture. The transmitter output and
the receiver input are protected to ±15kV using IEC
1000-4-2 Air-Gap Discharge, ±8kV using IEC 1000-4-2
Contact Discharge, and ±15kV using the Human Body
Model.
The transmitter has a low-dropout output stage provid-
ing minimum RS-232-compatible ±3.7V output levels
while driving 3kΩand 1000pF at 460kbps. Both +5V
and -5V must be supplied externally.
The MAX3314E has a SHDN function that reduces sup-
ply current to 1µA. The transmitter is disabled and put
into tristate while the receiver remains active.
The MAX3314E is available in 8-pin µMAX, SOT23, and
SO packages.
________________________Applications
Digital Cameras
PDAs
GPS
POS
Telecommunications
Handy-Terminals
Set-Top Boxes
Features
♦ESD Protection for RS-232 I/O Pins
±15kV—Human Body Model
±8kV—IEC 1000-4-2 Contact Discharge
±15kV—IEC 1000-4-2 Air-Gap Discharge
♦1µA Low-Power Shutdown with Receiver Active
♦30µA Operating Supply Current
♦460kbps Guaranteed Data Rate
♦8-Pin SOT23 Package
♦±3.7V RS-232-Compatible Levels
MAX3314E
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceiver
________________________________________________________________ Maxim Integrated Products 1
RIN
TOUTTIN
1
2
8
7
GND
V-
ROUT
VCC
SOT23/µMAX/SO
TOP VIEW
3
4
6
5
MAX3314E
SHDN
Pin Configuration
CBYPASS
0.1µF
2
7
1
8
5
6
4
3
SHDN
V-
TOUT
RIN
TIN
ROUT
VCC
GND
5kΩ
+5V
MAX3314E
CAPACITORS MAY BE POLARIZED OR NONPOLARIZED.
0.1µF
-5V
Typical Operating Circuit
19-1696; Rev 1; 3/01
Ordering Information
PART TEMP. RANGE PIN-PACKAGE
MAX3314ECKA-T 0°C to +70°C 8 SOT23-8
MAX3314ECUA 0°C to +70°C 8 µMAX
MAX3314ECSA 0°C to +70°C 8 SO
MAX3314EEKA-T -40°C to +85°C 8 SOT23-8
MAX3314EEUA -40°C to +85°C 8 µMAX
MAX3314EESA -40°C to +85°C 8 SO
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
MAX3314E
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceiver
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
VCC to GND.............................................................-0.3V to +6V
V- to GND ...............................................................+0.3V to -6V
Input Voltages
TIN, SHDN to GND ...............................................-0.3V to +6V
RIN to GND ......................................................................±25V
Output Voltages
TOUT to GND................................................................±13.2V
ROUT .................................................…-0.3V to (VCC + 0.3V)
Short-Circuit Duration
TOUT to GND .........................................................Continuous
Continuous Power Dissipation
8-Pin SOT23 (derate 9.7mW/°C above +70°C)...........777mW
8-Pin µMAX (derate 4.1mW/°C above +70°C) ............300mW
8-Pin SO (derate 5.88mW/°C above +70°C)...............471mW
Operating Temperature Ranges
MAX3314EC_A ..................................................0°C to +70°C
MAX3314EE_A................................................-40°C to +85°C
Junction Temperature.....................................................+150°C
Storage Temperature Range ............................-65°C to +150°C
Lead Temperature (soldering, 10s) ................................+300°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
DC CHARACTERISTICS
P osi ti ve S up p l y Op er ati ng Rang e VCC 4.75 5 5.25 V
N egati ve S up p l y Op er ating Range V- -4.75 -5 -5.25 V
Positive Supply Current SHDN = VCC, no load 30 100 µA
Negative Supply Current SHDN = VCC, no load 15 30 µA
Shutdown Supply Current SHDN = GND 1 10 µA
LOGIC INPUTS (TIN, SHDN)
Input Logic Threshold Low VIL 0.8 V
Input Logic Threshold High VIH 2.4 V
Transmitter Input Hysteresis 0.5 V
Input Leakage Current ±0.01 µA
RECEIVER OUTPUT
Output Voltage Low VOL IOUT = 1.6mA 0.4 V
Output Voltage High VOH IOUT = -1.0mA VCC
- 0.3
VCC
- 0.1 V
RECEIVER INPUT
Input Threshold Low VIL 0.8 V
Input Threshold High VIH 2.4 V
Input Hysteresis 0.5 V
Input Resistance 5 kΩ
TRANSMITTER OUTPUT
Output Voltage Swing Tr ansm i tter outp ut l oad ed w i th 3kΩ to g r ound ±3.7 V
Output Resistance (Note 1) VCC = V- = 0, transmitter output = ±2V 300 Ω
Output Short-Circuit Current ±60 mA
Output Leakage Current VOUT = ±12V, transmitter disabled 25 µA
ESD PROTECTION (Transmitter Output, Receiver Input)
Human Body Model ±15
IEC 1000-4-2 Air-Gap Discharge ±15
ESD-Protection Voltage
IEC 1000-4-2 Contact Discharge ±8
kV
ELECTRICAL CHARACTERISTICS
(VCC = +5V, V- = -5V, TA= TMIN to TMAX. Typical values are at TA= +25°C.)
MAX3314E
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceiver
_______________________________________________________________________________________ 3
Note 1: Not tested, guaranteed by design.
TIMING CHARACTERISTICS
(VCC = +5V, V- = -5V, TA= TMIN to TMAX. Typical values are at TA= +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Maximum Data Rate
RL = 3kΩ, CL = 1000pF, transmitter
switching 460
kbps
tPLH
Receiver input to receiver output,
CL = 150pF 0.15
Receiver Propagation Delay
tPHL
Receiver input to receiver output,
CL = 150pF 0.15
µs
Transmitter Skew 100 ns
Receiver Skew 50 ns
Transition Region Slew Rate RL = 3kΩ to 7kΩ, CL = 150pF to 1000pF,
measured from +3V to -3V or -3V to +3V
8 V/µs
0
2
1
5
4
3
8
7
6
9
0 1000500 1500 2000 2500 3000
SLEW RATE vs. LOAD CAPACITANCE
MAX3314E-01
LOAD CAPACITANCE (pF)
SLEW RATE (V/µs)
+SLEW
-SLEW
-6
1
-1
-2
2
3
5
4
6
0 1000 1500 2000 2500 3000
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3314E-02
LOAD CAPACITANCE (pF)
TRANSMITTER OUTPUT VOLTAGE (V)
0
-3
-4
-5
500
20kbps/120kbps 460kbps/250kbps
460kbps/250kbps
20kbps/120kbps
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
0 500 1000 1500 2000 2500 3000
SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3314E-03
LOAD CAPACITANCE (pF)
SUPPLY CURRENT (mA)
250kbps
120kbps
460kbps
20kbps
Typical Operating Characteristics
(VCC = +5V, V- = -5V, 250kbps data rate, transmitter loaded with 3kΩand CL, TA= +25°C, unless otherwise noted.)
MAX3314E
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceiver
4 _______________________________________________________________________________________
Detailed Description
RS-232-Compatible Drivers
The transmitter is an inverting level translator that con-
verts CMOS-logic levels to ±3.7V EIA/TIA-232-compati-
ble levels. It guarantees data rates up to 460kbps with
worst-case loads of 3kΩin parallel with 1000pF. When
SHDN is driven low, the transmitter is disabled and put
into tristate. The transmitter input does not have a pull-
up resistor. Connect to ground if unused.
RS-232-Compatible Receivers
The MAX3314E’s receiver converts RS-232 signals to
CMOS-logic output levels. The receiver is rated to
receive signals to ±25V. It will remain active during
shutdown mode.
MAX3314E Shutdown Mode
In shutdown mode, the transmitter output is put into high
impedance (Table 1). This reduces supply current to 1µA.
The time required to exit shutdown is less than 2.5µs.
Applications Information
Capacitor Selection
The capacitor type used is not critical for proper opera-
tion; either polarized or nonpolarized capacitors are
acceptable. If polarized capacitors are used, connect
polarity as shown in the Typical Operating Circuit.
Bypass VCC and V- to ground with at least 0.1µF.
Transmitter Outputs When
Exiting Shutdown
Figure 1 shows the transmitter output when exiting
shutdown mode. The transmitter is loaded with 3kΩin
parallel with 1000pF. The transmitter output displays no
ringing or undesirable transients as the MAX3314E
comes out of shutdown.
High Data Rates
The MAX3314E maintains minimum RS-232-compatible
±3.7V transmitter output voltage even at high data rates.
Figure 2 shows a transmitter loopback test circuit.
Figure 3 shows the loopback test result at 120kbps, and
Figure 4 shows the same test at 250kbps.
±15kV ESD Protection
As with all Maxim devices, ESD-protection structures are
incorporated on all pins to protect against electrostatic
discharges encountered during handling and assembly.
The MAX3314E driver outputs and receiver inputs have
extra protection against static discharge. Maxim’s engi-
neers have developed state-of-the-art structures to pro-
tect these pins against ESD of ±15kV without damage.
The ESD structures withstand high ESD in all states: nor-
mal operation, shutdown, and powered down. After an
ESD event, Maxim’s E versions keep working without
latchup, whereas competing products can latch and
must be powered down to remove latchup.
ESD protection can be tested in various ways. The trans-
mitter outputs and receiver inputs of the product family
are characterized for protection to the following limits:
•±15kV using the Human Body Model
•±8kV using the Contact Discharge method specified
in IEC 1000-4-2
•±15kV using the IEC 1000-4-2 Air-Gap method
Pin Description
PIN NAME FUNCTION
1V
CC +5V ±5% External Power Supply. Decouple with a 0.1µF capacitor to ground.
2SHDN Shutdown, Active low (0 = off, 1 = on).
3 ROUT TTL/CMOS Receiver Output
4 TIN TTL/CMOS Transmitter Input
5 TOUT RS-232-Compatible Transmitter Output
6 RIN RS-232-Compatible Receiver Input
7 V- -5V ±5% External Power Supply. Decouple with a 0.1µF capacitor to ground.
8 GND Ground
ESD Test Conditions
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents
test setup, test methodology, and test results.
Human Body Model
Figure 5 shows the Human Body Model, and Figure 6
shows the current waveform it generates when dis-
charged into low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the test device through a
1.5kΩresistor.
MAX3314E
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceiver
_______________________________________________________________________________________ 5
Table 1. Shutdown Logic Truth Table
SHDN TRANSMITTER
OUTPUT
RECEIVER
OUTPUT
L High Z Active
H Active Active
Figure 1. Transmitter Outputs When Exiting Shutdown or
Powering Up
1µs/div
SHDN
TOUT
5V/div
0
1.5V/div
0
TIN = GND
TIN = VCC
Figure 2. Loopback Test Circuit
0.1µF
SHDN
TOUT
RIN
TIN
ROUT
VCC
GND
5kΩ
+5V
MAX3314E
0.1µF
-5V
1000pF
V-
Figure 3. Loopback Test Result at 120kbps
5µs/div
TOUT
TIN
ROUT
Figure 4. Loopback Test Result at 250kbps
2µs/div
TOUT
TIN
ROUT
MAX3314E
IEC 1000-4-2
The IEC 1000-4-2 standard covers ESD testing and per-
formance of finished equipment; it does not specifically
refer to ICs. The MAX3314E helps design equipment
that meets Level 4 (the highest level) of IEC 1000-4-2
without the need for additional ESD-protection compo-
nents.
The major difference between tests done using the
Human Body Model and IEC 1000-4-2 is higher peak
current in IEC 1000-4-2 because series resistance is
lower in the IEC 1000-4-2 model. Hence, the ESD with-
stand voltage measured to IEC 1000-4-2 is generally
lower than that measured using the Human Body Model.
Figure 7 shows the IEC 1000-4-2 model, and Figure 8
shows the current waveform for the 8kV, IEC 1000-4-2,
Level 4, ESD Contact Discharge test.
The Air-Gap test involves approaching the device with a
charged probe. The Contact Discharge method connects
the probe to the device before the probe is energized.
Machine Model
The Machine Model for ESD tests all pins using a
200pF storage capacitor and zero discharge resis-
tance. Its objective is to emulate the stress caused by
contact that occurs with handling and assembly during
manufacturing. Of course, all pins require this protec-
tion during manufacturing, not just RS-232 inputs and
outputs. Therefore, after PC board assembly, the
Machine Model is less relevant to I/O ports.
Chip Information
TRANSISTOR COUNT: 128
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceiver
6 _______________________________________________________________________________________
CHARGE-CURRENT
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
100pF
RC
1MΩ
RD
1500Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 6. Human Body Current Waveform
IP 100%
90%
36.8%
tRL TIME
tDL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
Ir
10%
0
0
AMPERES
Figure 7. IEC 1000-4-2 ESD Test Model
CHARGE-CURRENT
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
150pF
RC
50MΩ to 100MΩ
RD
330Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 8. IEC 1000-4-2 ESD Generator Current Waveform
tr = 0.7ns to 1ns
30ns
60ns
t
100%
90%
10%
IPEAK
I
Figure 5. Human Body ESD Test Model
MAX3314E
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceiver
_______________________________________________________________________________________ 7
Package Information
8LUMAXD.EPS SOT23, 8L.EPS
MAX3314E
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceiver
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Package Information (continued)
SOICN.EPS
