2010 Microchip Technology Inc. DS21996D-page 1
MCP98242
Features:
• Temperature Sensor + 256 Byte Serial EEPROM
• EEPROM for Serial Presence Detect (SPD)
• Optimized for Voltage Range: 3.0V to 3.6V
• Shutdown/Standby Current: 3 µA (maximum)
• 2-wire Inte rface: I2C™/SMBus Compatible
• Available Packages: DFN-8, TDFN-8, UDFN-8,
TSSOP-8
Temperature Sensor Features:
• Temperature-to-Digital Converter
• Operating Current: 200 µA (typical)
•Accuracy:
- ±0.5°C/±1°C (typ./m ax .) +75°C to +95°C
- ±1°C/±2°C (typ./max.) +40°C to +125°C
- ±2°C/±3°C (typ./max.) -2 0°C to +125°C
Serial EEPROM Features:
• Operati ng Curren t:
-Write 1.1 mA (typical) for 3.5 ms (typical)
- Read 100 µA (typical)
• Permanent and Reversible Software Write-Protect
• Sof tware Write Protectio n fo r th e Low e r 12 8 B yte s
• Organized as 1 Block of 256 Bytes (256x8)
Typical Applications:
• DIMM Modules
• Laptops, Personal Computers and Servers
• Hard Disk Drives and Other PC Peripherals
Description:
Microchip Technology Inc.’s MCP98242 digital
temperature sensor converts temperature from -40°C
and +125°C to a digital word. This sensor meets
JEDEC Specification JC42.4 Mobile Platform Memory
Module Thermal Sensor Component. It provides an
accuracy of ±0.5°C/±1°C (typical/maximum) from
+75°C to +95°C. In addi tion, this devic e has an interna l
256 Byte E EPROM which can be used to store memory
module and vendor information.
The MC P982 42 dig ital temperat ure sensor co me s w i th
user-programmable registers that provide flexibility for
DIMM temperature-s en si ng ap pl ica tio ns . The re gis ters
allow user-selectable settings such as Shutdown or
Low-Power modes and the specification of
temperature event and critical output boundaries.
When the temperature changes beyond the specified
boundary limits, the MCP98242 outputs an Event
signal. The user has the option of setting the Event
output signal polarity as either an active-low or
active-high comparator output for thermostat operation,
or as a temperature event interrupt output for
microprocessor-based systems. The Event output can
also be configured as a critical temperature output.
The EEPROM is designed specifically for DRAM
DIMMs (Dual In-line Memory Modules) Serial Presence
Detect (SPD). The lower 128 bytes (address 00h to
7Fh) can be Permanent Write-Protected (PWP) or
Software Reversible Write-Protected (SWP). This
allows DRAM vendor and product information to be
stored and write-protected. The upper 128 bytes
(address 80h to FFh) can be used for general purpose
data s torage. These a ddresses are not wri te-protected.
This sensor has an industry standard 2-wire, I2C/
SMBus co mp atible seria l inter face, a llow ing up to eig ht
devices to be controlled in a single serial bus. To
maintain interchangeability with the I2C/SMBus
interface th e electrical speci fications are specified with
the operating voltage of 3.0V to 3.6V. In addition, a
40 ms (typical) time out is implemented.
Package Types
Memory
DIMM MODULE
Temperature Sensor + EEPROM
MCP98242
3.3VDD_SPD SDA SCL
• ±0.5°C (typ.) Sensor
• 256 Byte EEPROM for SPD
Event
8-Pin DFN/TDFN/UDFN (2x3) *
SDA
GND
Event
SCLK
MCP98242
1
2
3
4
8-Pin TSSOP
A0 VDD
A1
A2
8
7
6
5
A2
A1
GND
Event
SCLK
1
2
3
4
8
7
6
5SDA
VDD
A0
EP
9
* Includes Exposed Thermal Pad (EP); see Table 3-1.
Memory Modul e Temperature Sensor w/EEPROM for SPD
MCP98242
DS21996D-page 2 2010 Microchip Technology Inc.
Notes:
2010 Microchip Technology Inc. DS21996D-page 3
MCP98242
1.0 ELECTRICAL
CHARACTERISTICS
Absolute Maximum Ratings †
VDD.................................................................................. 6.0V
Voltage at all Input/Output pins...............GND – 0.3V to 6.0V
Pin A0 ................................................... GND – 0.3V to 12.5V
Storage temperature ............. .. .... .. .. ....... .. .. .. .-65°C to +150°C
Ambient temp. with power applied. ...............- 40°C to +125°C
Junction Temperature (TJ) ..........................................+150°C
ESD protection on all pins (HBM:MM) ..... .... .. .... ..(4 kV:300V)
Latch-Up Current at each pin (+25°C) ..................... ±200 mA
†Notice: Stresses above those listed under “Maximum
ratings” may c ause permanent dam age to the device. This is
a stress rating only and functional operation of the device at
those or any other conditions above those indicated in the
operational listings of this specification is not implied.
Exposure to m aximum rating conditions for extended periods
may affect device reliability.
DC CHARACTERISTICS
Electrical Specifications: Unless otherwise indicated, VDD = 3.0V to 3.6V, GND = Ground, SDA/SCL pulled-up to
VDD, and TA = -20°C to +125°C.
Parameters Sym Min Typ Max Unit Conditions
Power Supply
Operati ng Voltage VDD 3.0 — 3.6 V
Operati ng Curren t
Temperature Sensor IDD — 200 500 µA EEPROM Inactive
EEPROM write IDD — 1100 2000 µA Sensor in Shutdow n mode (for tWC)
EEPROM read IDD — 100 500 µA Sensor in Shutdown mode
Shutdown Current ISHDN — 1 3 µA EEPROM Inactive,
Sensor in Shut dow n mode
Power-on-Reset (POR)
Threshold VPOR — 2.3 — V Temperature Sens or (VDD falling)
VPOR — 1.6 — V EEPROM (VDD falling) (see Section 5.4
“Summary of Temperature Sensor
Power-on Default”)
Power Supply Rejection,
TA = +25°C
°C/VDD —±0.4—°C/VV
DD = 3.0V to 3.6V
°C/VDD —±0.15— °CV
DD = 3.3V+150 mVPP AC (0 to 1 MHz)
Temperature Sensor Accuracy
+75°C < TA +95°C TACY -1.0 ±0.5 +1.0 °C
+40°C < TA +125°C TACY -2.0 ±1 +2.0 °C
-20°C < TA +125°C TACY -3.0 ±2 +3.0 °C
TA -40°C TACY —-2—°C
Conversion Time
0.25°C/bit tCONV — 65 125 ms 15 s/sec (typical) (See Section 5.2.3.3
“Temperature Resolution”)
Event Output (Open-drain)
High-level Current (leakage) IOH ——1µAV
OH = VDD
Low-level Voltage VOL ——0.4VI
OL= 3 mA
EEPROM
Write Cycle (byte /page) tWC —35ms—
Endurance TA = +25°C — 1M — — cycles VDD = 5V, Note 1
Write-Protect High Voltage VHI_WP 8 — 12 V Applied at A0 pin, Note 1
Thermal Response
Note 1: Char acterized but not production tested.
MCP98242
DS21996D-page 4 2010 Microchip Technology Inc.
GRAPHICAL SYMBOL DESCRIPTION
DFN tRES — 0.7 — s Time to 63% (89°C)
25°C (Air) to 125°C (oil bath)
TSSOP tRES —1.4— s
DC CHARACTERISTICS
Electrical Specifications: Unless otherwise indicated, VDD = 3.0V to 3.6V, GND = Ground, SDA/SCL pulled-up to
VDD, and TA = -20°C to +125°C.
Parameters Sym Min Typ Max Unit Conditions
Note 1: Char acterized but not production tested.
INPUT/OUTPUT PIN DC CHARACTERISTICS
Electrical Specifications: Unless otherwise indicated, VDD = 3.0V to 3.6V, GND = Ground and
TA = -20°C to +125°C.
Parameters Sym Min Typ Max Units Conditions
Serial Input/Output (SCL, SDA, A0, A1, A2)
Input
High-level Voltage VIH 2.1 — — V
Low-level Voltage VIL ——0.8V
Input Current IIN ——±5µA
Output (SDA)
Low-level Voltage VOL ——0.4VI
OL= 3 mA
High-level Current (leakage) IOH ——1µAV
OH = VDD
Low-level Current IOL 6——mAV
OL = 0.6V
Capacitance CIN —5—pF
SDA and SCL Inputs
Hysteresis VHYST —0.5—V
Note: The serial inputs do not load the serial bus for VDD range of 1.8V to 5.5V.
VDD VIH
VIL
IIN
Voltage
Current
time
VDD
IOH
Voltage
Current
time
INPUT OUTPUT
VOL
IOL
TEMPERATURE CHARACTERISTICS
Electrical Specifications: Unless otherwise indicated, VDD = 3.0V to 3.6V, GND = Ground.
Parameters Sym Min Typ Max Units Conditions
Temperature Ranges
Specified Temperature Range TA-20 — +125 °C (Note 1)
Operati ng Tempe rature Range TA-40 — +125 °C
Storage Temperature Range TA-65 — +150 °C
Thermal Package Resistances
Note 1: Operation in this range must not cause TJ to exceed Maximum Junction Temperature (+150°C).
2010 Microchip Technology Inc. DS21996D-page 5
MCP98242
0
TIMING DIAGRAM
Thermal Resistance, 8L-DFN JA — 84.5 — °C/W
Thermal Resistance, 8L-TDFN JA —41—°C/W
Thermal Resistance, 8L-TSSOP JA —139—°C/W
TEMPERATURE CHARACTERISTICS
Electrical Specifications: Unless otherwise indicated, VDD = 3.0V to 3.6V, GND = Ground.
Parameters Sym Min Typ Max Units Conditions
Note 1: Operation in this range must not cause TJ to exceed Maximum Junction Temperature (+150°C).
SENSOR AND EEPROM SERIAL INTERFACE TIMING SPECIFICATIONS
Electrical Specifications: Unless otherwise indicated, VDD = 3.0V to 3.6V, GND = Ground, TA = -20°C to +125°C,
CL = 80 pF, and all limits measured to 50% point.
Parameters Sym Min Typ Max Units Conditions
2-Wire I2C™/SMBus-Compatible Interface
Serial Port Frequency fSC 10 — 100 kHz I2C™/SMBus
Low Clock tLOW 4.7 — — µs
High Clock tHIGH 4.0 — — µs
Rise Time tR— — 1000 ns (VIL MAX - 0.15V) to (VIH MIN +
0.15V)
Fall Time tF— — 300 ns (VIH MIN + 0.15V) to (VIL MAX -
0.15V)
Data Setup Before SCLK High tSU-DATA 250 — — ns
Data Hold After SCLK Low tH-DATA 300 — — ns
Start Condition Setup Time tSU-START 4.7 — — µs
Start Condition Hold Time tH-START 4.0 — — µs
Stop Condition Setup Time tSU-STOP 4.0 — — µs
Bus Idle tB_FREE 4.7 — — µs
Time Out tOUT 2 5 40 5 0 ms Temp. Sensor Only (characterized
but not production tested)
tSU-START
tH-START
tSU-DATA
tSU-STOP
tB-FREE
SCLK
SDA
tH-DATA
tHIGH
tLOW
tOUT
tR, tF
Start Conditi on Data Transmission Stop Condition
MCP98242
DS21996D-page 6 2010 Microchip Technology Inc.
NOTES:
2010 Microchip Technology Inc. DS21996D-page 7
MCP98242
2.0 TYPICAL PERFORMANCE CURVES
Note: Unless otherwise indicated, VDD = 3.0V to 3.6V, GND = Ground, SDA/SCL pulled-up to VDD, and
TA = -20°C to +125°C.
FIGURE 2-1: Average Tem peratu re
Accuracy.
FIGURE 2-2: Temperature Accuracy
Histogram, TA = +95°C.
FIGURE 2-3: Temperature Accuracy
Histogram, TA = +75°C.
FIGURE 2-4: Supply Current vs.
Temperature.
FIGURE 2-5: Shutdown Current vs.
Temperature.
FIGURE 2-6: Power-on Reset Threshold
Voltage vs. Temperature.
Note: The gra phs and tab les prov ided fo llow ing this note are a sta tistic al sum mary b ased on a limit ed numb er of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.
-3.0
-2.0
-1.0
0.0
1.0
2.0
3.0
-40-20 0 20406080100120
TA (°C)
Temperature Accuracy (°C)
VDD= 3.0V to 3.6V
Spec. Limits
0%
10%
20%
30%
40%
50%
60%
70%
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
Temperature Accuracy (°C)
Occurrences
TA = +95°C
VDD = 3.3V
221 units
0%
10%
20%
30%
40%
50%
60%
70%
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
Temperature Accuracy (°C)
Occurrences
TA = +75°C
VDD = 3.3V
221 units
1
10
100
1000
10000
-40 -20 0 20 40 60 80 100 120
TA (°C)
IDD (µA)
VDD = 3.3V to 3.6V
EEPROM Write (Sensor in Shutdown Mode)
Sensor (EEPROM Inactive)
EEPROM Read (Sensor in Shutdown Mode)
0.00
0.50
1.00
1.50
2.00
2.50
3.00
-40 -20 0 20 40 60 80 100 120
TA (°C )
ISHDN (µA)
VDD = 3.0V to 3.6V
0
0.5
1
1.5
2
2.5
3
-40 -20 0 20 40 60 80 100 120
TA (°C)
VPOR (V)
MCP98242
DS21996D-page 8 2010 Microchip Technology Inc.
Note: Unless otherwise indicated, VDD = 3.0V to 3.6V, GND = Ground, SDA/SCL pulled-up to VDD, and
TA = -20°C to +125°C.
FIGURE 2-7: Event and SDA VOL vs.
Temperature.
FIGURE 2-8: Conversion Rate vs.
Temperature.
FIGURE 2-9: Power Supply Rejection vs.
Frequency.
FIGURE 2-10: SDA IOL vs. Temperature.
FIGURE 2-11: Temperature Accuracy vs.
VDD.
FIGURE 2-12: Package Thermal
Response.
0
0.1
0.2
0.3
0.4
-40-200 20406080100120
TA (°C)
Event & SDA V OL (V)
Event
SDA
VDD = 3.0V to 3.6V
IOL = 3 mA
35
50
65
80
95
110
125
-40-20 0 20406080100120
TA (°C)
tCONV (ms)
VDD = 3.0V to 3.6V
-1.0
-0.5
0.0
0.5
1.0
100 1,000 10,000 100,000 1,000,000
Frequency (Hz)
Normalized Temp. Error (°C)
Δ°C/ΔVDD, VDD = 3.3V + 150 mVPP (AC)
1k 10k 100k 1M100k 1M10k 100k 1M1k 10k 100k 1M
100 1k 10k 100k 1M
TA = +25°C
No decoupling capacitor
6
12
18
24
30
36
42
48
-40 -20 0 20 40 60 80 100 120
TA (°C)
SDA IOL (mA)
VDD = 3.0V to 3.6V
VOL = 0.6V
-3.0
-2.0
-1.0
0.0
1.0
2.0
3.0
-40-200 20406080100120
TA (°C)
Temperature Accuracy (°C)
VDD
= 3.0V
VDD
= 3.6V
Δ°C/ΔVDD = 0.4°C/V
0%
20%
40%
60%
80%
100%
120%
-2 0 2 4 6 8 10 12 14 16
Time (s)
Thermal Response (%)
22°C (Air) to 125°C (Oil bath)
TSSOP-8
DFN-8
2010 Microchip Technology Inc. DS21996D-page 9
MCP98242
3.0 PIN DESCRIPTION
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1: PIN FUNCTION TABLES
3.1 Address Pins (A2, A1, A0)
These pins are device address input pins.
The address pins correspond to the Least Significant
bits (LSb) of address bits. The Most Significant bits
(MSb) (A6, A5, A4, A3). This is shown in Table 3-2.
3.2 Ground Pin (GND)
The GND pin is the system ground pin.
3.3 Serial Data Line (SDA)
SDA is a bidirectional input/output pin, used to serially
transmit data to/from the host controller. This pin
requires a pull-up resistor. (See Section 4.0 “Serial
Communication”).
3.4 Serial Clock Line (SCLK)
The SCLK is a clock input pin. All communication and
timing is relative to the signal on this pin. The clock is
generated by the host or master controller on the bus.
(See Section 4.0 “Serial Communication”).
3.5 Open-Drain Temperature Alert
Output (Event)
The MCP982 42 Event pi n is an op en- drain ou tput. Th e
devi ce outputs a signal when the ambient tempera ture
goes beyond the user-programmed temperature limit.
(see Section 5.2.3 “Event Output Configuration”).
3.6 Power Pin (VDD)
VDD is the power pin. The operating voltage range, as
specified in the DC electrical specification table, is
applied on this pin.
3.7 Exposed Thermal Pad (EP)
There is an internal electrical connection between the
Exposed Thermal Pad (EP) and the GND pin; they
must be connected t o the same p otential on th e Printed
Circuit Board (PCB).
DFN/TDFN/
UDFN TSSOP Symbol Pin Function Package Type
1 1 A0 Slav e Addre ss
2 2 A1 Slav e Addre ss
3 3 A2 Slav e Addre ss
44 GNDGround
5 5 SDA Serial Data Line
6 6 SCLK Serial Clock Line
7 7 Event Temperature Alert Output
88 V
DD Power Pin
9 — EP Exposed Thermal Pad (EP);
must be connected to VSS.
SDA
GND
Event
SCLK
1
2
3
4
8-Pin TSSOP
A0 VDD
A1
A2
8
7
6
5
TABLE 3-2: MCP98242 ADDRESS BYTE
Device Address Code Slave
Address
A6 A5 A4 A3 A2 A1 A0
Sensor 0011
XXX
EEPROM 1010
EEPROM
Write-Protect 0110
Note: User-selectable address is shown by X.
MCP98242
DS21996D-page 10 2010 Microchip Technology Inc.
NOTES:
2010 Microchip Technology Inc. DS21996D-page 11
MCP98242
4.0 SERIAL COMMUNICATION
4.1 2-Wire SMBus/Standard Mode
I2C™ Protocol-Compatible
Interface
The MCP98242 serial clock input (SCLK) and the
bidirectional serial data line (SDA) form a 2-wire
bidirectional SMBus/Standard mode I2C compatible
communication port (refer to the Input/Output Pin DC
Characteristics Table and Sen sor And EEPROM Seria l
Interface Timing Specifications Table).
The following bus protocol has been defined:
TABLE 4-1: MCP98242 SERIAL BUS
PROTOCOL DESCRIPTIONS
4.1.1 DATA TRANSFER
Data tra nsfer s are in itiat ed by a Start co nditio n (Start) ,
follow ed b y a 7-bi t dev ic e ad dre ss and a rea d/wri te bi t.
An Acknowledge (ACK) from the slave confirms the
reception of each byte. Each access must be
terminated by a Stop condition (Stop).
Repeated communication is initiated after tB-FREE.
This device does not support sequential register read/
write. Each register needs to be addressed using the
Register Pointer.
This device supports the Receive Protocol. The
register can be spe ci fie d u si ng the po inter for the ini tia l
read. Each rep eated read or receive be gins with a S ta rt
condition and address byte. The MCP98242 retains the
previously selected register. Therefore, it outputs data
from the previousl y-speci fied register ( repeate d pointer
specification is not necessary).
4.1.2 MASTER/SLAVE
The bus is controlled by a master device (typically a
microcontroller) that controls the bus access and
generates the Start and Stop conditions. The
MCP982 42 is a slave device and does not con trol other
devi ce s in the bus. Both mas te r and sl ave devices ca n
operate as either transmitter or receiver. However, the
master device determines which mode is activated.
4.1.3 START/STOP CONDITION
A hig h- to - lo w t ran si t i on of t h e SD A l i ne (w hi l e SC LK is
high) is the Start condition. All data transfers must be
prece ded by a S tart condi tion from the maste r . If a S ta rt
condition is generated during data transfer, the
MCP982 42 reset s and acc epts th e new Start condit ion.
A low -t o -h i gh t r an si ti on of t he S DA l i ne (w hi l e SC LK is
high) signifies a Stop condition. If a Stop condition is
introduced during data transmission, the MCP98242
releases the bus. All data transfers are ended by a S top
condition from the master.
4.1.4 ADDRESS BYTE
Follow ing the S t art condi tion, the host mus t transmit an
8-bit address byte to the MCP98242. The address for
the MCP98242 Temperature Sensor is
‘0011,A2,A1,A0’ in binary, where the A2, A1 and A0
bits are set externally by co nne cti ng th e correspon din g
pins to VDD ‘1’ or GND ‘0’. The 7-bit address transmit-
ted in the serial bit stream must match the selected
address for the MCP98 242 to respond with a n ACK. Bit
8 in the address byte is a read/write bit. Setting this bit
to ‘1’ c ommands a read ope ration , whil e ‘0’ commands
a write operati on (se e Figure 4-1).
Term Description
Master The device that controls the serial bus,
typically a microcontroller.
Slave The device addressed by the master,
such as the MCP98242.
Transmitter Device sending data to the bus.
Receiver Device receiving data from the bus.
Start A unique signal from master to initiate
serial interface with a slave.
Stop A unique signal from the master to
terminate serial interface from a slave.
Read/Write A read or write to the MCP98242
registers.
ACK A receiver Acknowledges (ACK) the
reception of each byte by polling the
bus.
NAK A receiver Not-A ck nowl edg es (NAK) or
releases the bus to show End-of-Data
(EOD).
Busy Communication is not possible
because the bus is in use.
Not Busy The bus is in the Idle state, both SDA
and SCLK remain high.
Data Valid SDA must remain stable before SCLK
becomes high in order for a data bit to
be considered valid. During normal
dat a transfe rs, SDA only cha nges st ate
while SCLK is low.
MCP98242
DS21996D-page 12 2010 Microchip Technology Inc.
FIGURE 4-1: Device Addressing.
4.1.5 DATA VALID
After the Start condition, each bit of data in
transmi ssion needs to be settled for a tim e specifi ed by
tSU-DATA before SCLK toggles from low-to-high (see
“Sensor And EEPROM Serial Interface Timing
Specifications” on Page 5).
4.1.6 ACKNOWLEDGE (ACK)
Each receiving device, when addressed, is obliged to
generate an ACK bit after the reception of each byte.
The master device must generate an extra clock pulse
for ACK to be recognized.
The ackno w led gin g dev ic e pul ls down the SDA lin e for
tSU-DATA before the lo w-to-high transi tion o f SCL K from
the master. SDA also needs to remain pulled down for
tH-DATA after a high-to-low transition of SCLK.
During read, the master must signal an End-of-Data
(EOD) to the slave by no t genera ting an ACK bit (NAK)
onc e the l ast b it ha s been cloc ked ou t of the sl ave. I n
this case, the slave will leave the data line released to
enable the master to generate the Stop condition.
4.1.7 TIME OUT (MCP98242)
If the SCLK st ays lo w or high for time s pecified by tOUT,
the MCP98242 temperature sensor resets the serial
interface. This dictates the minimum clock speed as
specified in the SMBus specification. However, the
EEPROM does not reset the serial interface.
Therefore, the master can hold the clock indefinitely to
process data from the EEPROM.
123456789
SCLK
SDA 0011A2 A1 A0
Start
Address Byte
Slave
Address R/W
MCP98242 Response
Code Address
A
C
K
2010 Microchip Technology Inc. DS21996D-page 13
MCP98242
5.0 FUNCTIONAL DESCRIPTION
The MCP98242 temperature sensors consists of a
band gap type temperature sensor, a Delta-Sigma Ana-
log-to-Digital Converter ( ADC), user-programmable
registers and a 2-wire I2C/SMBus protocol compatible
serial interface. Figure 5-1 shows a block diagram of
the register struct ure.
FIGURE 5-1: Functional Block Diagram.
Clear Event
0.5°C/bit
0.25°C/bit
0.125°C/bit
0.0625°C/bit
Temperature
TUPPER
TLOWER
Configuration
ADC
Band-Gap
Temperature
Sensor
Event Status
Output Control
Critical Event only
Even t Polar ity
Event Comp/Int
TCRIT
Capability
Temp. Range
Accuracy
Output Feature
Register
Pointer
Critical Tr ip Lock
Alarm Win. Lock Bit
Shutdown
Hysteresis
Manufacturer ID
Resolution
Memory
Control
Logic
Address
Standard
Array
Write-
Write-Protect
Circuitry
Sense Amp
R/W Control
Protected
(00h-7Fh)
(80h-FFh)
Device ID/R ev
Selected Resolution
HV Generator
Decoder
Array
X
Address Decoder
Y
SMBus/Standard I2C™
Interface
A0 A1 A2 Event SDA SCL VDD GND
Temperature Sensor EEPROM
MCP98242
DS21996D-page 14 2010 Microchip Technology Inc.
5.1 Registers
The MCP98242 has several registers that are
user-ac cessibl e. Thes e regis ters in clude the Cap abi lit y
register, Configuration register, Event Temperature
Upper-Boundary and Lower-Boundary Trip registers,
Critical Temperature Trip register, Temperature
register, Manufacturer Identification register and
Device Iden tifi ca tio n regis ter.
The Temperature register is read-only, used to access
the ambient temperature data. The data is loaded in
parallel to this register after tCONV. The Event
Temperature Upper-Boundary and Lower-Boundary
Trip registers are read/writes. If the ambient
temperature drifts beyond the user-specified limits, the
MCP98242 outputs a signal using the Event pin (refer
to Section 5.2.3 “Event Output Configuration”). In
addition, the Critical Temperature Trip register is used
to provide an additional critical temperature limit.
The Capability register is used to provide bits
describ ing the MCP9 8242’s cap abi lity in measureme nt
resolution, measurement range and device accuracy.
The device Configuration register provides access to
configure the MCP98242’s various features. These
registers are described in further detail in the following
sections.
The registers are accessed by sending a Register
Pointer to the MCP98242 using the serial interface.
This is an 8-bit write-only pointer. However, the three
Least Significant bits are used as pointers and all
unused bits (bits 7-3) need to be cleared or set to ‘0’.
Register 5-1 describes the pointer or the address of
each register.
REGISTER 5-1: REGISTER POINTER (WRITE ONLY)
W-0 W-0 W-0 W-0 W-0 W-0 W-0 W-0
— — — — Pointer Bits
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-4 Writable Bits: Write ‘0’’
Bits 7- 4 must a lways be cl eared or wri tten to ‘0’. T his d evi ce ha s add itiona l r egiste rs that ar e rese rve d
for test and calibration. If these registers are accessed, the device may not perform according to the
specification.
bit 3-0 Pointer Bits:
0000 = Capability register
0001 = Configuration register (CONFIG)
0010 = Event Temperature Upper-Boundary Trip register (TUPPER)
0011 = Event Temperature Lower-Boundary Trip register (TLOWER)
0100 = Critical Temperature Trip register (TCRIT)
0101 = Temperature register (TA)
0110 = Manufacturer ID register
0111 = Device ID/Revision register
1000 = Resolution register
1XXX = Reserved
2010 Microchip Technology Inc. DS21996D-page 15
MCP98242
TABLE 5-1: BIT ASSIGNMENT SUMMARY FOR ALL REGISTERS (SEE SECTION 5.4)
Register
Pointer
(Hex)
MSB/
LSB
Bit Assignment
76 5 43210
0x00 MSB 0 0 0 0 0 0 0 0
LSB 0 0 0 Resolution Range Accuracy Event
0x01 MSB 0 0 0 0 0 Hysteresis SHDN
LSB Crt Loc Win Loc Int Clr Evt Stat Evt Cnt Evt Sel Evt Pol Evt Pol
0x02 MSB 0 0 0 SIGN 27°C 26°C 25°C 24°C
LSB 23°C 22°C 21°C 20°C 2-1°C 2-2°C 0 0
0x03 MSB 0 0 0 SIGN 27°C 26°C 25°C 24°C
LSB 23°C 22°C 21°C 20°C 2-1°C 2-2°C 0 0
0x04 MSB 0 0 0 SIGN 27°C 26°C 25°C 24°C
LSB 23°C 22°C 21°C 20°C 2-1°C 2-2°C 0 0
0x05 MSB TA TCRIT TA TUPPER TA TLOWER SIGN 27°C 26°C 25°C 24°C
LSB 23°C 22°C 21°C 20°C 2-1°C 2-2°C 0 0
0x06 MSB 0 0 0 0 0 0 0 0
LSB 0 1 0 1 0 1 0 0
0x07 MSB 0 0 1 0 0 0 0 0
LSB 0 0 0 0 0 0 0 1
0x08 LSB 0 0 0 0 0 0 0 1
MCP98242
DS21996D-page 16 2010 Microchip Technology Inc.
5.1.1 CAPABILITY REGISTER
This is a read-only register used to identify the
temperature sensor capability. In this case, the
MCP98242 is capable of providing temperature at
0.25°C resolution, measuring temperature below and
above 0°C, providing ±1°C a nd ±2°C accurac y over the
active and monitor temperature ranges (respectively)
and providing user-programmable temperature event
boundary trip limits. Register 5-2 describes the
Capability register. These functions are described in
further detail in the following sections.
REGISTER 5-2: CAPABILITY REGISTER (READ-ONLY) ADDRESS ‘0000 0000’b
U-0 U-0 U-0 U-0 U-0 U-0 U-0 U-0
————————
bit 15 bit 8
U-0 U-0 U-0 R-0 R-1 R-1 R-1 R-1
— — — Resolution Meas Range Accuracy Temp Alarm
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 15-5 Unimplemented: Read as ‘0’
bit 4-3 Resolution:
00 = 0.5°C
01 = 0.25°C ( power-up default)
10 = 0.125°C
11 = 0.0625°C
These bits reflect the selected resolution (see Section 5.2.3.3 “Temperature Resolution”)
bit 2 Temperature Measurement Range (Meas. Range):
0 =T
A 0 (decimal) for temperature below 0°C
1 = The part can measure temperature below 0°C (power-up default)
bit 1 Accuracy:
0 =Accuracy ±2°C from +75°C to +95°C (Active Range) and ±3°C from +40°C to +125°C
(Monitor Range)
1 =Accuracy ±1°C from +75°C to +95°C (Active Range) and ±2°C from +40°C to +125°C
(Monitor Range)
bit 0 Temperature Alarm:
0 = No defined function (This bit will never be cleared or set to ‘0’).
1 = The part has temperature boundary trip limits (TUPPER/TLOWER/TCRIT registers) and a
temperau tre ev ent outp ut (JC 42.4 requ ire d featu re).
2010 Microchip Technology Inc. DS21996D-page 17
MCP98242
FIGURE 5-2: Timing Diagram for Reading the Capability Register (See Section 4.0 “Serial
Communication”).
SDA A
C
K
0011A
Capability Pointer
0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
A
C
K
0011
A
MSB Data
A
C
KN
A
K
S P
2A
1
A
0
12345678 12345678 12345678
Address Byte LSB Data
R
MCP98242 MCP98242
MCP98242 Master Master
W
SDA
SCLK
000
00000000 00001111
MCP98242
DS21996D-page 18 2010 Microchip Technology Inc.
5.1.2 SENSOR CONFIGURATION
REGISTER (CONFIG)
The MCP98242 has a 16-bit Configuration register
(CONFIG) that allows the user to set various func tions
for a robust temperature monitoring system. Bits 10
thru 0 are used to select Event output boundary
hysteresis, device Shutdown or Low-Power mode,
temperature boundary and critical temperature lock,
temperature Event output enable/disable. In addition,
the user can select the Event output condition (output
set for TUPPER and TLOWER temperature boundary or
TCRIT only), read Event output status and set Event
output polarity and mode (Comparator Output or
Interrupt Output mode).
The temperature hysteresis bits 10 and 9 can be used
to prevent output chatter when the ambient
temperature gradually changes beyond the
user-specified temperature boundary (see
Section 5.2.2 “Temperature Hysteresis (THYST)”.
The Continuous Conversion or Shutdown mode is
selected using bit 8. In Shutdown mode, the band gap
temperature sensor circuit stops converting
temperature and the Ambient Temperature register
(TA) holds the previous successfully converted
temperature data (see Section 5.2.1 “Shutdown
Mode”). Bits 7 and 6 are used to lock the
user-specified boundaries TUPPER, TLOWER and TCRIT
to prevent an accidental rewrite. Bits 5 thru 0 are used
to configure the temperature Event output pin. All
functions are described in Register 5-3 (see
Section 5.2.3 “Event Output Configuration”).
REGISTER 5-3: CONFIGURATION REGISTER (CONFIG) ADDRESS ‘0000 0001’b
U-0 U-0 U-0 U-0 U-0 R/W-0 R/W-0 R/W-0
————— T
HYST SHDN
bit 15 bit 8
R/W-0 R/W-0 R/W-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0
Crit. Lock Win. Lock Int. Clear Event Stat. Event Cnt. Event Sel. Event Pol. Event Mod.
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 15-11 Unimplements: Read as ‘0’
bit 10-9 TUPPER and TLOWER Limit Hysteresis (THYST):
00 = 0°C (power-up default)
01 = 1.5°C
10 = 3.0°C
11 = 6.0°C
This bit cannot be altered when either of the lock bits are set (bit 6 and bit 7), refer to Section 5.2.3
“Event Output Configuration”.
bit 8 Shutdown Mode (SHDN):
0 = Continuous Conversion (power-up default)
1 = Shutdown (Low-Power mode)
In shut down, all po wer-consumin g activitie s are disabled , though all registers can be written to or read.
This bit ca nnot be set ‘1’ w h en either of the l ock b it s i s se t (bit 6 and bit 7 ) . Ho w eve r, it can be cleared
‘0’ for Continuo us C onv ers io n while loc ked. (Re fer to Section 5.2.1 “Shutdown Mode”)
2010 Microchip Technology Inc. DS21996D-page 19
MCP98242
bit 7 TCRIT Lock Bit (Crit. Lock):
0 = Unlocked. TCRIT register can be written. (power-up default)
1 =Locked. T
CRIT register cannot be written
When enabled, this bit remains set ‘1’ or locked until cleared by internal Reset (Section 5.4 “Sum-
mary of Temperature Sensor Power-on Default”). This bit does not require a double-write.
bit 6 TUPPER and TLOWER Window Lock Bit (Win. Lock):
0 = Unlocked. TUPPER and TLOWER registers can be written. (power-up default)
1 =Locked. T
UPPER and TLOWER registers cannot be written
When enabled, this bit remains set ‘1’ or locked until cleared by internal Reset (Section 5.4 “Sum-
mary of Temperature Sensor Power-on Default”). This bit does not require a double-write.
bit 5 Interrupt Clear (Int. Clear) Bit:
0 = No effect (power-up default)
1 = Clear interrupt output. When read this bit returns ‘0’
bit 4 Event Output Status (Event Stat.) Bit:
0 = Event output is not asserted by the device (power-up default)
1 = Event output is asserted as a comparator/Interrupt or critical temperature output
bit 3 Event Output Control (Event Cnt.) Bit:
0 = Disabled (power-up default)
1 = Enabled
This bit cannot be altered when either of the lock bits is set (bit 6 and bit 7).
bit 2 Event Output Select (Event Sel.) Bit:
0 = Event output for TUPPER, TLOWER and TCRIT (power-up defaul t)
1 = TA > TCRIT only. (TUPPER and TLOWER temperature boundaries are disabled.)
When the Alarm Window Lock bit is set, this bit cannot be altered until unlocked (bit 6).
bit 1 Event Output Polarity (Event Pol.) Bit:
0 = Active-low (power-up default)
1 = Active-high
This bit cannot be altered when either of the lock bits is set (bit 6 and bit 7).
bit 0 Event Output Mode (Event Mod.) Bit:
0 = Comparator output (power-up default)
1 = Interrupt output
This bit cannot be altered when either of the lock bits is set (bit 6 and bit 7).
REGISTER 5-3: CONFIGURATION REGISTER (CONFIG) ADDRESS ‘0000 0001’b
MCP98242
DS21996D-page 20 2010 Microchip Technology Inc.
FIGURE 5-3: Timing Diagram for Writing and Reading from the Configuration Register (See
Section 4.0 “Serial Communication”).
SDA A
C
K
0011A
Configuration Pointer
0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
A
C
K
0011A
MSB Data
A
C
KN
A
K
S P
2A
1A
0
12345678 12345678 12345678
Address Byte LSB Data
R
MCP98242 MCP98242
MCP98242 Master Master
W
SDA
SCLK
001
00000000 00001000
• Readi ng the CONF IG R egi ste r.
• Writing to the CONFIG Register to Enable the Event Output pin <0000 0000 0000 1000>b.
SDA A
C
K
0011A0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
W
MCP98242 MCP98242
MSB Data
A
C
KA
C
KP
12345678 12345678
LSB Data
Configu rati on Pointer
MCP98242 MCP98242
001
00000000 00001000
Note: It is not necessary to
select the Register
Pointer if it was set
from the previous read/
write.
2010 Microchip Technology Inc. DS21996D-page 21
MCP98242
5.1.3 UPPER/LOWER/CRITICAL
TEMPERATURE LIMIT REGISTERS
(TUPPER/TLOWER/TCRIT)
The MCP98242 has a 16-bit read/write Event output
Temperature Upper-Bou ndary T rip re gister (TUPPER), a
16-bit Lower-Boundary Trip register (TLOWER) and a
16-bit Critical Boundary Trip register (TCRIT) that
contains 11-bit data in two’s complement format
(0.25 °C). This data represents the maximum and
minimum temperature boundary or temperature
window that can be used to monitor ambient
temperature. If this feature is enabled (Section 5.1.2
“Sensor Configuration Register (CONFIG)”) and the
ambient temperature exceeds the specified boundary
or window, the MCP98242 asserts an Event output.
(Refer to Section 5.2.3 “Event Output
Configuration”).
REGISTER 5-4: UPPER/LOWER/CRITICAL TEMPERATURE LIMIT REGISTER (TUPPER/TLOWER/
TCRIT) ADDRESS ‘0000 0010’b/‘0000 0011’b‘0000 0100’b
U-0 U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
———Sign2
7°C 26°C 25°C 24°C
bit 15 bit 8
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 U-0 U-0
23°C 22°C 21°C 20°C 2-1°C 2-2°C — —
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 15-1 3 Unimplemented: Read as ‘0’
bit 12 Sign:
0 =T
A 0°C
1 =T
A 0°C
bit 11-2 TUPPER/TLOWER/TCRIT
:
Temperature boundary trip data in two’s complement format.
bit 1-0 Unimplemented: Read as ‘0’
Note: This table shows two 16-bit registers for TUPPER, TLOWER and TCRIT located at ‘0000 0010b’,
‘0000 0011b’ and ‘0000 0100b’, respectively.
MCP98242
DS21996D-page 22 2010 Microchip Technology Inc.
FIGURE 5-4: Timing Diagram for Writing and Reading from the TUPPER Register (See Section 4.0
“Serial Communication”).
SDA A
C
K
0011A
TUPPER Pointer
0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
A
C
K
0011A
MSB Data
A
C
KN
A
K
S P
2A
1A
0
12345678 12345678 12345678
Address Byte LSB Data
R
MCP98242 MCP98242
MCP98242 Master Master
W
SDA
SCLK
010
00000101 10100000
• Reading from the TUPPER Register.
• Writing 90°C to the TUPPER Register <0000 0101 1010 0000>b.
SDA A
C
K
0011A0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
W
MCP98242 MCP98242
MSB Data
A
C
KA
C
KP
12345678 12345678
LSB Data
TUPPER Pointer
MCP98242 MCP98242
010
00000101 10100000
Note: It is not necessary to
select the Register
Pointer if it was se t from
the previous read/write.
2010 Microchip Technology Inc. DS21996D-page 23
MCP98242
5.1.4 AMBIENT TEMPERATURE
REGISTER (TA)
The MCP98242 uses a band gap temperature sensor
circuit to output anal og volt age proporti onal to abs olute
temperat ure. An intern al ADC is used to co nvert the
analog voltage to a digital word. The converter
resolution is set to 0.25 °C + sign (11-bit data). The
digital word is loaded to a 16-bit read-only Ambient
Temperature register (TA) that contains 11-bit
temperature data in two’s complement format.
The TA regis ter bits (bit s 12 thru 0) ar e double-buf fered.
Therefore , the user can access the register whil e, in the
background, the MCP98242 performs an analog-to-
digital conversion. The temperature data from the
ADC is loaded in parallel to the TA register at tCONV
refresh rate.
The TA magnitude in decimal to ambient temperature
conversion is shown in Equation 5-1:
EQUATION 5-1: DECIMAL CODE TO
TEMPERATURE
CONVERSION
In addition, the TA register uses three bits (bits 15, 14
and 13) to reflect the Event pin state. This allows the
user to identify the cause of the Event output trigger
(see Section 5.2.3 “Event Output Configuration”);
bit 15 i s s et to ‘ 1’ i f TA is greater than or equa l to TCRIT,
bit 14 is set to ‘1’ i f T A is greater t han TUPPER and bit 13
is set to ‘1’ if TA is less than TLOWER.
The TA register bit assignment and boundary
conditions are described in Register 5-5.
TACode 2 4–
=
Where:
TA= Ambient Temperature (°C)
Code = MCP98242 temperature output
magnitude in decimal (bits 0-11)
REGISTER 5-5: AMBIENT TEMPERATURE REGISTER (TA) ADDRESS ‘0000 0101’b
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0
TA vs. TCRIT TA vs. TUPPER TA vs. TLOWER SIGN 27 °C 26 °C 25 °C 24 °C
bit 15 bit 8
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0
23 °C 22 °C 21 °C 20 °C 2-1 °C 2-2 °C — —
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 15 TA vs. TCRIT ( 1) Bit:
0 =T
A TCRIT
1 =T
A TCRIT
bit 14 TA vs. TUPPER (1) Bit:
0 =T
A TUPPER
1 =T
A TUPPER
bit 13 TA vs. TLOWER (1) Bit:
0 =T
A TLOWER
1 =T
A TLOWER
bit 12 SIGN Bit:
0 =T
A 0°C
1 =T
A 0°C
bit 11-2 Ambient Temperature (TA) Bits:
10-bit Ambient Temperature data in two’s complement format.
bit 1-0 TA: Dat a in 2’ s complem ent format. D epending on the statu s of the Reso lution Regis ter (Register 5-8),
these bits may display 2-3°C (0.125°C) and 2-4°C (0.0625°C), respectively.
Note 1: Not affected by the status of the Event output Configuration (bits 5 to 0 of CONFIG), Register 5-3.
MCP98242
DS21996D-page 24 2010 Microchip Technology Inc.
FIGURE 5-5: Timing Diagram for Reading +25.25°C Temperature from the TA Register (See
Section 4.0 “Serial Communication”).
SDA A
C
K
0011A
TA Pointer
0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
A
C
K
0011A
MSB Data
A
C
KN
A
K
S P
2A
1A
0
12345678 12345678 12345678
Address Byte LSB Data
R
MCP98242 MCP98242
MCP98242 Master Master
W
SDA
SCLK
101
00000001 10010100
Note: It is not necessary to
select the Register
Pointer if it was set
from the previous read/
write.
2010 Microchip Technology Inc. DS21996D-page 25
MCP98242
5.1.5 MANUFACTURER ID REGISTER
This regi st er is us ed to identify th e m anu fac ture r of th e
device in order to perform manufacturer specific
operation. The Manufacturer ID for the MCP98242 is
0x0054 (hexadecimal).
FIGURE 5-6: Timing Diagram for Reading the Manufacturer ID Register (See Section 4.0 “Serial
Communication”).
REGISTER 5-6: MANUFACTURER ID REGISTER (READ-ONLY) ADDRESS ‘0000 0110’b
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-0
Manufactur er ID
bit 15 bit 8
R-0 R-1 R-0 R-1 R-0 R-1 R-0 R-0
Manufactur er ID
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 15-0 Device Manufacturer Identification Number
.
SDA A
C
K
0011A
Manuf. ID Pointer
0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
A
C
K
0011A
MSB Data
A
C
KN
A
K
S P
2A
1A
0
12345678 12345678 12345678
Address Byte LSB Data
R
MCP98242 MCP98242
MCP98242 Master Master
W
SDA
SCLK
110
00000000 01010100
Note: It is not necessary to
select the Register
Pointer if it was set
from the previous read/
write.
MCP98242
DS21996D-page 26 2010 Microchip Technology Inc.
5.1.6 DEVICE ID AND REVISION
REGISTER
The upper byte of this register is used to specify the
device identification and the lower byte is used to
specify device revision. The device ID for the
MCP98242 is 0x21 (hex).
The revision begins with 0x00 (hex) for the first release,
with the number being incremented as revised versions
are released.
FIGURE 5-7: Timing Diagram for Reading Devi ce ID and Device Revision Register (See Section 4.0
“Serial Communication”).
REGISTER 5-7: DEVICE ID AND DEVICE REVISION (READ-ONLY) ADDRESS ‘0000 0111’b
R-0 R-0 R-1 R-0 R-0 R-0 R-0 R-0
Devi ce ID
bit 15 bit 8
R-0 R-0 R-0 R-0 R-0 R-0 R-0 R-1
Device Revision
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 15-8 Device ID: Bit 15 to bit 8 are used for device ID
bit 7-0 Device Revision: Bit 7 to bit 0 are used for device revision
SDA A
C
K
0011A
Device ID Pointer
0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
A
C
K
0011A
MSB Data
A
C
KN
A
K
S P
2A
1A
0
12345678 12345678 12345678
Address Byte LSB Data
R
MCP98242 MCP98242
MCP98242 Master Master
W
SDA
SCLK
111
00100000 00000000
Note: It is not necessary to
select the Register
Pointer if it was set
from the previous read/
write.
2010 Microchip Technology Inc. DS21996D-page 27
MCP98242
5.1.7 RESOLUTION REGISTER
This register allows the user to change the sensor
resolution (see Section 5.2.3.3 “Temperature
Resolution”). The POR default resolution is 0.25°C.
The selected resolution is also reflected in the
Cap ab ili ty regi st er (see Register 5-2).
FIGURE 5-8: Timing Diagram for Changing TA Resolution to 0.0625°C <0000 0011>b (See
Section 4.0 “Serial Communication”).
REGISTER 5-8: RESOLUTION ADDRESS ‘0000 1000’b
U-0 U-0 U-0 U-0 U-0 U-0 R/W-0 R/W-0
—————— Resolution
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-2 Unimplemented: Read as ‘0’
bit 1-0 Resolution:
00 = LSB = 0.5°C (tCONV = 30 ms typical)
01 = LSB = 0.25°C (power-up default, tCONV = 65 ms typical)
10 = LSB = 0.125°C (tCONV = 130 ms typical)
11 = LSB = 0.0625°C (tCONV = 260 ms typical)
SDA A
C
K
0011AA
C
K
S2A
1A
0
12345678 12345678
SCLK
Address Byte
W
MCP98242 MCP98242
A
C
KP
12345678
Data
Resolution Pointer
MCP98242
00001000 00000011
MCP98242
DS21996D-page 28 2010 Microchip Technology Inc.
5.2 SENSOR FEATURE DESCRIPTION
5.2.1 SHUTDOWN MODE
Shutdown mode disables all power-consuming
activities (including temperature sampling operations)
while leaving the serial interface active. This mode is
select ed by setting bit 8 of CONFIG to ‘ 1’. In this mode,
the device consumes ISHDN. It remains in this mode
until bit 8 is cleared ‘0’ to enable Continuous
Conversion mode, or until power is recycled.
The Shutdown bit (bit 8) cannot be set to ‘1’ while bits
6 and 7 of CONFIG (Lock bits) are set to ‘1’. However,
it can be cleared ‘0’ or returned to Continuous
Conve r si on wh il e lock ed .
In Shut down m ode, all registe rs can be read or written.
However , the serial bus activity increases the shutdown
current. In addition, if the device is shutdown while the
Event pin is asserted as active-low or deasserted
active-low (see Section 5.2.3.1 “Comparator Mode”),
the device will retain the active-low state. This
increases the shutdown current due to the additional
Event output pull-down current.
5.2.2 TEMPERATURE HYSTERESIS
(THYST)
A hysteres is of 0°C , 1.5°C, 3°C or 6°C can be s electe d
for the TUPPER, TLOWER and TCRIT temperate
boundaries using bits 10 and 9 of CONFIG. The
hystere sis applies for decreasing te mperature onl y (hot
to cold), or as temperature drifts below the specified
limit.
The TUPPER, TLOWER and TCRIT boundary conditions
are described graphically in Figure 5-2.
5.2.3 EVENT OUTPUT CONFIGURATION
The Event output can be enabled using bit 3 of
CONFIG (Event output control bit) and can be
configured as either a comparator output or as Interrupt
Output m ode using bit 0 of CON FIG (Event mode). The
polarity can also be specified as an active-high or
active-low using bit 1 of CONFIG (Event polarity).
When the ambient temperature increases above the
critica l tempera ture limit , the Event output is forced to a
comparator output (regardless of bit 0 of CONFIG).
When the temperature drifts below the critical
temperature limit minus hysteresis, the Event output
automatically returns to the state specified by bit 0 of
CONFIG.
The status of the Event output can be read using bit 4
of CONFIG (Event status).
Bit 7 and 6 of the CONFIG register can be used to lock
the TUPPER, TLOWER and TCRIT registers. The bits
prevent false triggers at the Event output due to an
accidental rewrite to these registers.
The Event output can also be used as a critical
temperature output using bit 2 of CONFIG (critical
output only). When this feature is selected, the Event
output bec omes a comp arator outp ut. In this mode , the
interrupt output configuration (bit 0 of CONFIG) is
ignored.
5.2.3.1 Comparator Mod e
Comparator mode is selected using bit 0 of CONFIG. In
this mode, the Ev ent output is asserted as active-high
or active-low using bit 1 of CONFIG. Figure 5-2 shows
the conditions that toggle the Event output.
If the device enters Shutdown mode with asserted
Event output, the output remains asserted during
Shutdown. The device must be operating in
Continuous Conversion mode for tCONV; the TA vs.
TUPPER, TLOWER and TCRIT boundary conditions need
to be s atisf ied i n or der fo r the Event output to de asse rt.
Comparator mode is useful for thermostat-type
applications, such as turning on a cooling fan or
triggering a system shutdown when the temperature
exceeds a safe operating range.
5.2.3.2 Interrupt Mode
In the Interrupt mode, the Event output is asserted as
active-high or active-low (depending on the polarity
configuration) when TA drifts above or below TUPPER
and TLOWER limits. The outp ut is deass erted by se tting
bit 5 (Interrupt Clear) of CONFIG. Note that when
switching from Comparator mode to Interrupt mode, it
is recommended to send interrupt clear command (set
bit 5) to reset the interrupt flag. Shutting down the
device will not reset or deassert the Event output. This
mode cannot be selected when the Event output is
used as critical temperature output only, using bit 2 of
CONFIG. This mode is designed for interrupt driven
microcontroller-based systems. The microcontroller
receiving the interrupt will have to acknowledge the
interrupt by setting bit 5 of CONFIG register from the
MCP98242.
5.2.3.3 Temp eratur e Resolution
The MCP98242 is capable of providing a temperature
data w ith 0.5°C to 0.0625°C resolutio n. The Resolutio n
can be selected using the Resolution register
(Register 5-8) which is located in address
‘00001000’b. This address location is not specified in
JEDEC Standard JC42.4. However, it provides
additional flexibility while being functionally compatible
with JC42 .4 and prov ide a 0.2 5°C res olutio n at 125 ms
(maximum). The selected resolution can be read by
user using bit 4 and bit 3 of the Capability register
(Register 5-2). A 0.25°C resolution is set as POR
default by factory.
2010 Microchip Technology Inc. DS21996D-page 29
MCP98242
TABLE 5-2: TEMPERATURE
CONVERSION TIME
FIGURE 5-9: Event Output Condition.
Resolution tCONV
(ms)
Samples/sec
(typical)
0.5°C 30 33
0.25°C
(POR default) 65 15
0.125°C 130 8
0.0625°C 260 4
TUPPER
TLOWER
Event Output
TCRIT
TA
TUPPER - THYST
(Active-Low)
Comparator
Interrupt
S/w Int. Clear
Crit ic al On ly
TCRIT - THYST
123456
Note Event Output Boundary
Conditions
Event Output TA Bits
Comparator Interrupt Critical 15 14 13
1T
A TLOWER HLH000
2T
A TLOWER - THYST LLH001
3T
A TUPPER LLH010
4 T
A TUPPER - THYST HLH000
5 T
A TCRIT LLL110
6T
A TCRIT - THYST LHH010
* When TA TCRIT and TA TCRIT - T HYST the Event output is Comparator mode and bits 0 of
CONFIG (Event output mode) is ignored.
TLOWER -THYST
TLOWER -THYST
TUPPER - THYST
1342
Note: *
MCP98242
DS21996D-page 30 2010 Microchip Technology Inc.
5.3 EEPROM FEATURE
DESCRIPTION
5.3.1 BYTE WRITE
To write a byte in the MCP98242 EEPROM, the master
has to specify the memory location or address. Once
the address byte is transmitted correctly followed by a
word address, the word address is stored in the
EEPROM Address Pointer. The following byte is data
to be stored in the specified memory location.
Figure 5-10 shows the timing diagram.
FIGURE 5-10: Timing Diagram for Byte Write (See Section 4.0 “Serial Communication”).
SDA A
C
K
1010AA
C
K
S2A
1A
0
12345678 12345678
SCLK
Address Byte
W
MCP98242 MCP98242
A
C
KP
12345678
Data
Word Address
MCP98242
XXXXXXX X XXXXXXXX
2010 Microchip Technology Inc. DS21996D-page 31
MCP98242
5.3.2 PAGE WRITE
The write Address Byte, word address and the first data
byte are transmit ted to the MCP9824 2 in the s ame way
as in a byte write. Instead of generating a Stop
conditi on, th e mas ter tran smit s u p to 15 addi tional dat a
bytes to the MCP98242, which are temporarily stored
in the on-chip page buffer and will be written into the
memory after the master has transmitted a Stop
condition. Upon receipt of each word, the four lower
order Address Pointer bits are internally incremented
by o ne. T h e hi ghe r o rde r f o ur bi ts of th e w ord a d dr ess
remain constant. If the master should transmit more
than 1 6 bytes p rior to gen erating the S top cond ition, the
address counter will roll over and the previously
receive d dat a wil l be overwri tten. As with the by te writ e
operation, once the Stop condition is received, an
internal write cycle will begin (Figure 5-11).
FIGURE 5-11: Timing Diagram for Page Write (See Section 4.0 “Serial Communication”).
Note: Page write operat ions are limited to writing
bytes within a single physical page,
regardless of the number of bytes actually
being written. Physical page boundaries
start at addresses that are integer
multiples of the page buffer size (or ‘page
size’) and end at addresses that are
integer multiples of [page size - 1]. If a
Page Write command attempts to write
across a physical page boundary, the
result is that the data wraps around to the
beginning of the current page (overwriting
data previously stored there), instead of
being wr itten to the next p age, as might be
expected. It is therefore necessary for the
application software to prevent page write
operations that would attempt to cross a
page boundary.
SDA A
C
K
1010AXXXX A
C
K
S2A
1A
0
12345678 12345678
SCLK
X
Address Byte
W
MCP98242 MCP98242
Data at (n)
A
C
KP
12345678 12345678
Data at (n+1)
Word Address (n)
MCP98242 MCP98242
XXX
XXXXXXXX XXXXXXXX A
C
K
Data at (n+15)
MCP98242
XXX XXX
A
C
K
Note: ‘n ’ is the in itial address for a page.
MCP98242
DS21996D-page 32 2010 Microchip Technology Inc.
5.3.3 WRITE PROTECTION
The MCP98242 has a Software Write-Protect (SWP)
feature that allows the lower half array (addresses
00h -7Fh) to be write-protected or permanently
write-protected (PWP). The write-protected area can
be cleared by sending Clear Write-Protect (CWP)
command. However, once the PWP is executed the
protected memory can not be cleared. The device will
not respond to the CWP command.
To access write protection, the device address code of
the Address Byte is set to ‘0110’ instead of ‘1010’.
The ‘1010’ Address code is used to access the mem-
ory area and the ‘0110’ address code is used to
access the write protection. Once the device is write-
protected it will not acknowledge certain commands.
Table 5-3 shows the corresponding Address Bytes for
the write-protect f eature.
TABLE 5-3: WRITE-PROTECT DEVICE ADDRESSING
TABLE 5-4: DEVICE RESPONSE WHEN WRITING DATA OR ACCESSING SWP/CWP/PWP
EEPROM Operation
Address Pins Address Byte
A2 A1 A0 Address Code
Slave Address
R/W
A2 A1 A0
SWP WRITE GND GND VHI_A0 0110 0 0 1 0
READ 1
CWP WRITE GND VDD VHI_A0 0110 0 1 1 0
READ 1
PWP (Note)WRITEXXX0110 X X X 0
READ 1
Note: The address pins are ‘X’ or don’t cares. However, the slave address bits need to match the address pins.
Status Command ACK Address ACK Data Byte ACK Write Cycle
Not
Protected SWP/CWP/PWP ACK X ACK X ACK Yes
Page/byte write ACK Address ACK Data ACK Yes
Protected
with
SWP
SWP NoACK X NoACK X NoACK No
CWP ACK X ACK X ACK Yes
PWP ACK X ACK X ACK Yes
Page/byte write lower 128 bytes ACK Address ACK Data NoACK No
Permanently
Protected SWP/CWP/PWP NoACK X NoACK X NoACK No
Page/byte write lower 128 bytes ACK Address ACK Data NoACK No
Note: X is defined as ‘don’t care’.
2010 Microchip Technology Inc. DS21996D-page 33
MCP98242
5.3.3.1 Software Write-Protect (SWP)
The SWP feature is invoked by writing to the
write-protect register. This is done by sending an
Address Byte similar to a normal Write command.
Figure 5-14 shows the timing diagram. SWP can be
cleared using the CWP command. See
Section 5.3.3.2 “Clear Write-Protect (CWP)”.
The Slave Address bits need to correspond to the
address pin logic configuration. For SWP, a high
voltage VHI_WP needs to be applied to the A0 pi n and
the corre spond ing sl ave a ddress need s to be set t o ‘1’,
as shown in Table 5-3. Both A2 and A1 pins are
groun ded and the correspond ing slave ad dress bit s are
set to ‘0’.
The device response in this mode is shown in
Table 5-4 and Table 5-5.
FIGURE 5-12: Timing Diagram for Setting Software Write-Protect (See Section 4.0 “Serial
Communication”).
5.3.3.2 Clear Write-Protect (CWP)
The CWP feature is invoked by writing to the clear
write-protect register. This is done by sending an
Address Byte similar to a normal Write command.
Figure 5-14 shows the timing diagram. CWP clears
SWP only. PWP can not be cleared using this
command.
The Slave Address bits need to correspond to the
address pin logic configuration. For CWP, a high
voltage VHI_WP needs to be applied to the A0 pi n and
the corre spond ing sl ave a ddress need s to be set t o ‘1’.
The A1 pin is set to VDD and the corresponding slave
address bit is set to ‘1’. And A2 pin is set to ground
and the c orresp onding slav e addre ss bi ts a re set t o ‘0’.
Table 5-3 shows the bit configuration. The device
response in this mode is shown in Table 5-4 and
Table 5-5.
FIGURE 5-13: Timing Diagram for Setting Clear Write-Protect (See Section 4.0 “Serial
Communication”).
SDA A
C
K
0110 A
C
K
S
12345678 12345678
SCLK
Address Byte
W
MCP98242 MCP98242
A
C
KP
12345678
Data
Word Addre ss
MCP98242
XXXXXXXX XXXXXXXX
001
Note: Apply VHI_WP at A0 pin and connect GND to A1 and A2 pins to initiate SWP cycle.
SDA A
C
K
0110 A
C
K
S
12345678 12345678
SCLK
Address Byte
W
MCP98242 MCP98242
A
C
KP
12345678
Data
Word Addre ss
MCP98242
XXXXXXXX XXXXXXXX
011
Note: Apply VHI_WP at A0 pin, apply VDD at A1 pin, connect A2 pin to GND to initiate CWP cycle.
MCP98242
DS21996D-page 34 2010 Microchip Technology Inc.
5.3.3.3 PWP (Permanent Write-Protect)
Once the PWP register is written, the lower half of the
memory will be permanent protected and the device
will not acknowledge any command. The protected
area of the memory can not be cleared, reversed, or
re-written. If a write is attempted to the protected area,
the devic e will acknowled ge the address by te and word
address but not the data byte. (See Table 5-4 and
Table 5-5).
Unlike SWP and CWP, a VHI_WP is not applied on the
A0 pin to execute PWP. The state of A2, A1, and A0 is
user selectable. However, the address pin states need
to matc h the s lave addres s bit s, a s shown in Table 5-3.
FIGURE 5-14: Timing Diagram for Setting Permanently Write-Protect (See Section 4.0 “Serial
Communication”).
Note: Once the Permanent Write-Protect is
executed, it cannot be reversed, even if
the device power is cycled.
SDA A
C
K
0110AA
C
K
S2A
1A
0
12345678 12345678
SCLK
Address Byte
W
MCP98242 MCP98242
A
C
KP
12345678
Data
Word Addre ss
MCP98242
XXXXXXXX XXXXXXXX
Note: Unlike SWP and CWP, a VHI_WP is not applied on the A0 pin to execute PWP.
2010 Microchip Technology Inc. DS21996D-page 35
MCP98242
5.3.4 READ OPERATION
Read operations are initiated in the same way as write
operations, with the exception that the R/W bit of the
slave address is set to ‘1’. There are three basic types
of read operat ions: curren t address read, ra ndom rea d,
and sequential read.
TABLE 5-5: DEVICE RESPONSE WHEN READING SWP/CWP/PWP
5.3.4.1 Current Ad dr es s Read
The MCP98242 contains an address counter that
maintains the address of the last word accessed,
internal ly inc rem en ted b y ‘1’. Therefore, if th e p rev iou s
access (either a read or write operation) was to
address n, the next current address read operation
would access data from addres s n+1. Upon receipt of
the slave address with R/W bit set to ‘1’, the MCP98242
issues an Acknowledge and transmits the 8-bit data
word. The master will not acknowledge (NAK) the
transfer but does generate a Stop condition and the
MCP98 242 disc onti nu es tran sm is si on (Figure 5-15).
FIGURE 5-15: Reading Current Word Address (See Section 4.0 “Serial Communication”).
Status Command ACK Address ACK Data Byte ACK
Not Protected SWP/CWP/PWP ACK X NoACK X NoACK
Protected with SWP SWP NoACK X NoACK X NoACK
CWP ACK X NoACK X NoACK
PWP ACK X NoACK X NoACK
Permanently Protected SWP/CWP/PWP NoACK X NoACK X NoACK
Note: X is defined as ‘don’t care’.
1010AA
C
KN
A
K
S P
2A
1A
0
12345678 12345678
Address Byte Current Word Address
R
MCP98242 Master
SDA
SCLK
00000000
Note: In this example, the current word address is the
previously accessed address location n plus 1.
MCP98242
DS21996D-page 36 2010 Microchip Technology Inc.
5.3.4.2 Random Read
Random read operations allow the master to access
any memory location in a random manner. To perform
this typ e of re ad ope ratio n, the word add res s mus t firs t
be set. This is done b y sendi ng the word address to the
MCP98242 as part of a wr ite op erat ion . O nc e th e wo rd
address is sent, the master genera tes a Start co nditio n
following the Acknowledge. This terminates the write
operatio n, but not before the internal Address Pointer is
set. The master then issues the Address Byte again,
but with the R/W bit set to a ‘1’. The MCP98242 then
issues an Acknowledge and transmits the 8-bit data
word. Th e master w ill n ot acknow ledg e the tra nsfer but
does generate a Stop condition and the MCP98242
discontinues transmission (Figure 5-16).
FIGURE 5-16: Timing Diagram for Random Read (See Section 4.0 “Serial Communication”).
SDA A
C
K
1010A
Word Address (n)
0000 A
C
K
S2A
1A
0
12345678 12345678
SCLK
0
Address Byte
MCP98242 MCP98242
W000
1010AA
C
KN
A
K
S P
2A
1A
0
12345678 12345678
Address Byte Data at (n)
R
MCP98242 Master
SDA
SCLK
XXXXXXXX
Note: In this example, ‘n’ is the current Address Word which ‘00’h and the data is the byte at address ‘n’.
2010 Microchip Technology Inc. DS21996D-page 37
MCP98242
5.3.4.3 Seque nti al Read
Sequential reads are initiated in the same way as a
random read, with the exception that after the
MCP98242 transmits the first data byte, the master
issues an Acknowledge, as opposed to a Stop condi-
tion in a random read. This directs the MCP98242 to
transmit the next sequentially addressed 8-bit word
(Figure 5-17).
To provide sequential reads, the MCP98242 contains
an internal Address Pointer, which is incremented by
one at the completion of each operation. This Address
Pointer allows the entire memory contents to be serially
read during one operation.
FIGURE 5-17: Timing Diagram for Sequential Read (See Section 4.0 “Serial Communication”).
5.3.5 STANDBY MODE
The des ign w ill inc orporate a low -pow er Standb y mod e
(ISHDN). Standby mode will be entered after a normal
termination of any operation and after all internal
functions are complete. This would include any error
conditions occurring, such as improper number of clock
cycles or improper instruction byte as defined
previously.
SDA A
C
K
1010AXXXX A
C
K
S2A
1A
0
12345678 12345678
SCLK
X
Address Byte
R
MCP98242 MCP98242
Data at (n+1)
A
C
K
12345678 12345678
Data at (n+2)
Data (n)1
MCP98242 MCP98242
XXX
XXXXXXXX XXXXXXXX
Data at (n +m)(1)
XXX XXX
A
C
K
Note 1: ‘n’ is the initial address location and ‘m’ is the final address location (‘n+m’ < 256).
N
A
KP
Master
MCP98242
DS21996D-page 38 2010 Microchip Technology Inc.
5.4 Summary of Temperature Sensor
Power-on Default
The MCP98242 temperature sensor has an internal
Power-on Reset (POR) circuit. If the power supply
voltage VDD glitches down to the VPOR threshold, the
device resets the registers to the power-on default
settings.
Table 5-6 shows the power-on default summary.
TABLE 5-6: POWER-ON DEFAULTS
Registers Default Register
Data (Hexadecimal)
Power-up Default
Register Description
Address (Hexadecimal) Register Label
0x00 Capability 0x000F
0.25°
Measures temperature below 0°C
±1°C accuracy over active range
Temperature event outp ut
0x01 CONFIG 0x0000
Compar ator mode
Active-Low output
Event and critical output
Output disabled
Event not asser ted
Interr upt cl eare d
Event limits unlocked
Critical limit unlocked
Continuous conversion
0°C Hysteresis
0x02 TUPPER 0x0000 0°C
0x03 TLOWER 0x0000 0°C
0x04 TCRIT 0x0000 0°C
0x05 TA0x0000 0°C
0x06 Manufacturer ID 0x0054 0x0054 (hex)
0x07 Device ID/ Device Revision 0x2001 0x2001 (hex)
0x08 Resolution 0x01 0x01 (hex)
2010 Microchip Technology Inc. DS21996D-page 39
MCP98242
6.0 APPLICATIONS INFORMATION
6.1 Connecting to the Serial Bus
The SDA and SCLK serial interface pins are
open-drain pins that require pull-up resistors. This
configuration is shown in Figure 6-1.
FIGURE 6-1: Pull-up Resistors On Serial
Interface.
The number of devices connected to the bus is limited
only by the max imum rise and fall tim es of the SDA and
SCLK lines. Unlike I2C specific ations , SMBus do es not
specify a maximum bus capacitance value. Rather, the
SMBus specification requires that the maximum
current through the pull-up resistor be 350 µA and
minimum 100 µA. Because of this, the value of the
pull-up resistors will vary depending on the system’s
bias voltage (VDD). The pull-up resistor values for a
3.3 V system ranges 9 k to 33 k. Minimizing bus
capacitance is still very important as it directly affects
the rise and fall times of the SDA and SCLK lines.
Although SMBus specifications only require the SDA
and SCLK lines to pull-down 350 µA, with a maximum
voltage drop of 0.4 V, the MCP98242 is designed to
meet a maximum voltage drop of 0.4 V, with 3 mA of
current. This allows lower pull-up resistor values to be
used, allowing the MCP98242 to handle higher bus
capacitance. In such applications, all devices on the
bus must meet the same pull-down current
requirements.
A possible configuration using multiple devices on the
SMBus is shown in Figure 6-2.
FIGURE 6-2: Multiple Devices on DIMM
SMBus.
6.2 Layout Considerations
The MCP98242 does not require any additional
components besides the master controller in order to
measure temperature. However, it is recommended
that a decoupling capacitor of 0.1 µF to 1 µF be used
between the VDD and GND pins. A high-frequency
cera mic c a paci tor is re co mmen d ed . I t is ne c es sa ry fo r
the c apaci tor to be loc ate d as clo se a s po ssibl e to the
power and ground pins of the device in or der to provid e
effective noise protection.
6.3 Thermal Considerations
A potential for self-heating errors can exist if the
MCP98242 SDA, SCLK and Event lines are heavily
loaded with pull-ups (high current). Typically, the
self-hea tin g error is negligible be ca use of the relativel y
small current consumption of the MCP98242. A
temperature accuracy error of approximately 0.5°C
could re sult from sel f-heating if th e communicati on pins
sink/s ourc e the ma xi mum curre nt speci fied.
For exampl e, if the Event out put is load ed to maxim um
IOL, Equation 6-1 can be used to determine the effect
of self-heating.
EQUATION 6-1: EFFECT OF
SELF-HEATING
At room temperature (TA = +25°C) with maximum
IDD = 500 µA and VDD = 3.6V, the self-heating due to
power dissipation T is 0.2°C for the DFN-8 package
and 0.5°C for the TSS OP- 8 package.
SDA
SCLK
VDD
R
R
Microcontroller
MCP98242
Event
R
Master Slave
SDA SCLK
MCP98242
Temperature
Sensor 24LCS52
EEPROM
TJA VDD IDD VOL_Event IOL_Event VOL_SDA IOL_SDA
++=
Where:
T=T
J - TA
TJ= Junction Temperature
TA= Ambient Temperat ure
JA = Package Thermal Resistance
VOL_Event, SDA = Event and SDA Output VOL
(0.4 Vmax)
IOL_Event, SDA = Event and SDA Output IOL
(3 mAmax)
MCP98242
DS21996D-page 40 2010 Microchip Technology Inc.
NOTES:
2010 Microchip Technology Inc. DS21996D-page 41
MCP98242
7.0 PACKAGING INFORMATION
7.1 Package Marking Information
8-Lead DFN (MC) Example:
XXX
YWW
NN
ABJ
010
25
8-Lead TSSOP (ST) Example:
XXXX
YYWW
NNN
242B
E010
256
Legend: XX...X Customer-specific information
Y Year code (last digit of calendar year)
YY Year code (last 2 digits of calendar year)
WW Week code (week of January 1 is week ‘01’)
NNN Alphanu me ric trac ea bil ity code
Pb-free JEDEC designator for Matte Tin (Sn)
*This package is Pb-free. The Pb-f ree JEDEC designator ( )
can be found on the outer packaging for this package.
Note: In the ev ent the fu ll Mic rochip part nu mber ca nnot be m arked o n one lin e, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information.
3
e
3
e
8-Lead TDFN (MNY) Example:
XXX
YWW
NN
ABX
010
25
8-Le ad UDF N (MUY) Example:
XXX
YWW
NN
ABX
010
25
MCP98242
DS21996D-page 42 2010 Microchip Technology Inc.
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NOTE 1
12
EXPOSED PAD
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21
D2
K
L
E2
N
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b
A3 A1
A
NOTE 2
BOTTOM VIEW
TOP VIEW
2010 Microchip Technology Inc. DS21996D-page 43
MCP98242
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MCP98242
DS21996D-page 44 2010 Microchip Technology Inc.
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
2010 Microchip Technology Inc. DS21996D-page 45
MCP98242
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
MCP98242
DS21996D-page 46 2010 Microchip Technology Inc.
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DS21996D-page 48 2010 Microchip Technology Inc.
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MCP98242
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MCP98242
DS21996D-page 50 2010 Microchip Technology Inc.
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
2010 Microchip Technology Inc. DS21996D-page 51
MCP98242
APPENDIX A: REVISION HISTORY
Revision D (October 2010)
The following is the list of modifications:
1. Added the UDFN package.
Revision C (July 2009)
The following is the list of modifications:
1. Updated the DFN/TDFN package throughout
document.
2. Updated Table 5-1 and Table 5-6.
3. Updated Register 5-3, Register 5-5, Register 5-
7 and Register 5-8.
4. Updated Section 5.1.6 “Device ID and
Revision Register”.
5. Added Section 5.2.3.2 “Interrupt Mode”.
6. Updated Figure 5-9.
7. Section 7.0 “Packaging Information”:
Updated package outline drawings.
Revision B (February 2008)
The following is the list of modifications:
1. Added TDFN package throughout document.
Revision A (September 2006)
• Origin al Release of this Docu ment.
MCP98242
DS21996D-page 52 2010 Microchip Technology Inc.
NOTES:
2010 Microchip Technology Inc. DS21996D-page 53
MCP98242
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
Device: MCP98242: Digital Temperature Sensor
MCP98242T: Digital Temper ature Sensor
(Tape and Reel)
Grade: B = ±1°C (max.) from +75° C to +95°C,
B±2°C (max.) from +40° C to +125°C, and
B±3°C (max.) from -20°C to +125°C
Temperature Range: E = -40°C to +125°C
Package: MC = Dual Flat No Lead (2x3 mm Body), 8-lead,
MCBAC(1) = Dual Flat No Lead (2x3 mm Body), 8-lead,
MUY(2) = Dual Flat No Lead (2x3 mm Body), 8-lead,
MNY(2) = Dual Flat No Lead (2x3 mm Body), 8-lead,
MNYBAC(1,2) = Dual Flat No Lead (2x3 mm Body), 8-lead,
ST = Plastic Thin Shrink Small Outline
(4x4 mm Body), 8-lead
PART NO. X/XXX
PackageTemperature
Range
Device
Examples:
a) MCP98242-BE/MC: Extended Temp.,
8LD DFN pkg.
b) MCP98242T-BE/MC: Tape and Reel,
Extend ed Temp.,
8LD DFN pkg.
c) MCP98242-BE/ST: Extended Temp.,
8LD TSSOP pkg.
d) MCP98242T-BE/ST: Tape and Reel,
Extend ed Temp.,
8LD TSSOP pkg.
e) MCP98242-BE/MNY: Ext ended Temp.,
8LD TDFN (nickel
palla d iu m gold) pkg.
f) MCP98242-BE/MUY: Extended Temp.,
8LD UDFN (nickel
palla d iu m gold) pkg.
–X
Grade
Note 1: “Y” is Nickel Palladium Gold manufacturing designator. Only available
on the TDFN and UDFN packages for this family of products.
2: “BAC” is a n on-standa rd re el m anufa cturing desi gnator. It designa tes
parts in 8 m m wi de b y 4 m m w ide pi tc h ( Tape and R e el) on a 13 inch
reel with 11k base quantity.
MCP98242
DS21996D-page 54 2010 Microchip Technology Inc.
NOTES:
2010 Microchip Technology Inc. DS21996D-page 55
Information contained in this publication regarding device
applications a nd the lik e is provided only for your convenien ce
and may be su persed ed by upda t es . I t is y our responsibil it y to
ensure that your application meets with your specifications.
MICROCHIP MAKES NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND WHETHER EXPRESS OR
IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION,
INCLUDING BUT NOT LIMITED TO ITS CONDITION,
QUALITY, PERFORMANCE, MERCHANTABILITY OR
FITNESS FOR PURPOSE. Microchip disclaims all liability
arising from this information and its use. Use of Microchip
devices in life support and/or safety applications is entirely at
the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims,
suits, or expenses resulting from such use. No licenses are
conveyed, implicitly or otherwise, under any Microchip
intellectual property rights.
Trademarks
The Microchip name and logo, the Microchip logo, dsPIC,
KEELOQ, KEELOQ logo, MPLAB, PIC , PI Cmi cro, PI CSTART,
PIC32 logo, rfPIC and UNI/O are registered trademarks of
Microchip Technology Incorporated in the U.S.A. and other
countries.
FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor,
MXDEV, M XLA B, SE EVAL and The Embedded Control
Solutions Company are registered trademarks of Microchip
Technology Incorporated in the U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN,
ECONOMONIT OR, FanSense, HI-TIDE , In -Circuit Seri a l
Programming, ICSP, Mindi, MiWi, MPAS M, MPLA B Cert ified
logo, MPLIB, MPLINK, mTouch, Omniscient Code
Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit,
PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance,
TSHARC, UniWinDriver, WiperLock and ZENA are
trademarks of Microchip Technology Incorporated in the
U.S.A. and other countries.
SQTP is a service mark of Microchip T echnology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2010, Microchip Technology Inco rporated, Pr inted in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
ISBN: 978-1-60932-688-3
Note the following details of the code protection feature on Microchip devices:
• Microchip products meet the specification contained in their particular Microchip Data Sheet.
• Microchip believes that i ts family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
• Microchip is willing to work with the customer who is concerned about the integrity of their code.
• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is c onstantly evolving. We a t Microc hip are co m mitted to continuously improving the code prot ect ion featur es of our
products. Attempts to break Microchip’ s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Microchip received ISO/TS-16949:2002 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperiph erals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
DS21996D-page 56 2010 Microchip Technology Inc.
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08/04/10
