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MCP98244
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Datasheet MCP98244 Datasheet

MCP98244
DIMM MODULE
MCP98244
8-Pin 2x3 TDFN*
* Includes Exposed Thermal Pad (EP); see Tab le 3 -1 .
SCL
Event
SDA
A1
A2
1
2
3
4
8
7
6
5
GND
A0 V
DD
EP
9
DDR4 DIMM Temperature Sensor with EEPROM for SPD
Features
• Meets JEDEC Specification
- MCP98244 --> JC42.4-TSE2004B1 Temperature Sensor with 4 Kbit Serial EEPROM for Serial Presence Detect (SPD)
•1MHz, 2-wire I
• Specified V
• Operating Current: 100 µA (typ., EEPROM Idle)
• Available Package: TDFN-8
C™ Interface
Range: 1.7V to 3.6V
DD
Temperature Sensor Features
• Temperature-to-Digital Converter (°C)
• Sensor Accuracy (Grade B):
- ±0.2°C/±1°C (typ./max.)
- ±0.5°C/±2°C (typ./max.) +40°C to +125°C
- ±1°C/±3°C (typ./max.)
+75°C to +95°C
-40°C to +125°C
Serial EEPROM Features
• Operating Current:
-Write 250 µA (typical) for 3 ms (typical)
- Read 100 µA (typical)
• Reversible Software Write Protect
• Software Write Protection for each 1 Kbit Block
• Organized as two banks of 256 x 8-bit (2 Kbit x 2)
Typical Applications
• DIMM Modules for Servers, PCs, and Laptops
• Temperature Sensing for Solid State Drive (SSD)
• General Purpose Temperature Datalog
Description
Microchip Technology Inc.’s MCP98244 digital temperature sensor converts temperature from -40°C and +125°C to a digital word. This sensor meets JEDEC Specification JC42.4-TSE3000B1 Memory Module Thermal Sensor Component. It provides an accuracy of ±0.2°C/±1°C (typical/maximum) from +75°C to +95°C with an operating voltage of 1.7V to
3.6V. In addition, MCP98244 has an integrated EEPROM with two banks of 256 by 8 bit EEPROM (4k Bit) which can be used to store memory module details and vendor information.
The MCP98244 digital temperature sensor comes with user-programmable registers that provide flexibility for DIMM temperature-sensing applications. The registers allow user-selectable settings such as Shutdown or Low-Power modes and the specification of temperature Event boundaries. When the temperature changes beyond the specified Event boundary limits, the MCP98244 outputs an Alert signal at the Event pin. The user has the option of setting the temperature 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 MCP98244 EEPROM is designed specifically for DRAM DIMMs (Dual In-line Memory Modules) Serial Presence Detect (SPD). It has four 128 Byte pages, which can be Software Write Protected individually. This allows DRAM vendor and product information to be stored and write-protected.
This sensor has an industry standard I Plus compatible 1 MHz serial interface.
C Fast Mode

Package Types

2012-2013 Microchip Technology Inc. DS22327C-page 1
MCP98244
NOTES:
DS22327C-page 2 2012-2013 Microchip Technology Inc.
MCP98244

1.0 ELECTRICAL CHARACTERISTICS

Absolute Maximum Ratings †
VDD.................................................................................. 4.0V
Voltage at all Input/Output pins ............... GND – 0.3V to 4.0V
Pin A0 .......................................................GND – 0.3V to 11V
Storage temperature .....................................-65°C to +150°C
Ambient temp. with power applied ................-40°C to +125°C
Junction Temperature (T
ESD protection on all pins (HBM:MM) ................. (4 kV:200V)
Latch-Up Current at each pin (25°C) ....................... ±200 mA
) ..........................................+150°C
J
†Notice: Stresses above those listed under “Maximum ratings” may cause permanent damage 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 maximum rating conditions for extended periods may affect device reliability.

TEMPERATURE SENSOR DC CHARACTERISTICS

Electrical Specifications: Unless otherwise indicated, V
= -40°C to +125°C.
and T
A
Parameters Sym Min Typ Max Unit Conditions
Temperature Sensor Accuracy
+75°C < T
+95°C T
A
ACY
-1.0 ±0.2 +1.0 °C JC42.4 - TSE2004B1
+40°C < TA +125°C -2.0 ±0.5 +2.0 °C
-40°C < T
+125°C -3.0 ±1 +3.0 °C
A
Temperature Conversion Time
0.5°C/bit t
CONV
—30 — ms
0.25°C/bit — 65 125 ms 15 s/sec (typical) (See Section 5.2.4)
0.125°C/bit — 130 — ms
0.0625°C/bit — 260 — ms
Power Supply
Specified Voltage Range V
Operating Current I
DD_TS
Shutdown Current I
Power On Reset (POR) V
Settling Time after POR t
DD
SHDN
POR
POR
1.7 — 3.6 V
— 100 500 µA EEPROM Inactive
— 0.2 1 µA EEPROM Inactive, I2C Bus Inactive,
— 1.4 1.6 V Threshold for rising and falling V
— — 1 ms For warm and cold power cycles
Line Regulation °C — 0.2 — °C VDD = 1.7V to 3.6V
Event Output (Open-Drain output, external pull-up resistor required), see Section 5.2.3
High-Level Current (leakage) I
Low-Level Voltage V
OH
OL
—— 1 µAV
—— 0.4 VIOL= 3 mA (Active-Low, Pull-up
Thermal Response, from +25°C (Air) to +125°C (oil bath)
TDFN-8 t
RES
— 0.7 — s Time to 63% (89°C)
= 1.7V to 3.6V, GND = Ground,
DD
Grade B Accuracy Specification V
= 1.7V to 3.6V
DD
= 85°C
T
A
= V
OH
Resistor)
DD
DD
2012-2013 Microchip Technology Inc. DS22327C-page 3
MCP98244

MCP98244 EEPROM DC CHARACTERISTICS

Electrical Specifications: Unless otherwise indicated, V
= -40°C to +125°C.
and T
A
Parameters Sym Min Typ Max Unit Conditions
Current, EEPROM write (for tWC)I
Current, EEPROM read I
Write Cycle time (byte/page) t
Endurance T
EEPROM Write Temperature EE
EEPROM Read Temperature EE
Write Protect Voltage
SWP and CWP Voltage V
= +25°C — — 10k — cycles Write Cycles, V
A
DD_EE
DD_EE
WC
WRITE
READ
HV
— 250 2000 µA
— 100 500 µA
—3 5 ms
0— 85 °C
-40 — 125 °C For minimum read temperature, see Note 1
7 — 10 V Applied at A0 pin
Note 1: Characterized but not production tested.
2: For endurance estimates in a specific application, please consult the Total Endurance™ Model, which can
be obtained from Microchip’s web site at www.microchip.com/TotalEndurance

INPUT/OUTPUT PIN DC CHARACTERISTICS

Electrical Specifications: Unless otherwise indicated, V
= -40°C to +125°C.
T
A
Parameters Sym Min Typ Max Units Conditions
Serial Input/Output (SCL, SDA, A0, A1, A2) Input
High-Level Voltage V
Low-Level Voltage V
Input Current I
Input Impedance (A0, A1, A2) Z
Input Impedance (A0, A1, A2) Z
Output (SDA only)
Low-Level Voltage V
High-Level Current (leakage) I
Low-Level Current I
Capacitance C
SDA and SCL Inp uts
Hysteresis
V
Spike Suppression
IN
OL
OH
OL
HYST
T
SP
0.7V
IH
IL
IN
IN
IN
= 1.7V to 3.6V, GND = Ground,
DD
Sensor in Shutdown Mode
= 3.3V (Note 1, Note 2)
DD
.
= 1.7V to 3.6V, GND = Ground and
DD
DD
— — 0.3V
— — ±5 µA SDA and SCL only
—1—M VIN > V
— 200 — k VIN < V
——0.4VI
—— 1µAV
20 — — mA VOL = 0.4V; VDD ≥ 2.2V
6——mAV
—5—pF
— 0.05V
— — 50 ns
——V
V
DD
OL
OH
OL
—V
DD
IH
IL
= 3 mA
= V
= 0.6V
DD

TEMPERATURE CHARACTERISTICS

Electrical Specifications: Unless otherwise indicated, V
= -40°C to +125°C.
and T
A
Parameters Sym Min Typ Max Units Conditions
Temperature Ranges
Specified Temperature Range T
Operating Temperature Range T
Storage Temperature Range T
A
A
A
Thermal Package Resistances
Thermal Resistance, 8L-TDFN
Note 1: Operation in this range must not cause T
DS22327C-page 4 2012-2013 Microchip Technology Inc.
JA
J
= 1.7V to 3.6V, GND = Ground,
DD
-40 — +125 °C Note 1
-40 — +125 °C
-65 — +150 °C
—52.5— °C/W
to exceed Maximum Junction Temperature (+150°C).

SERIAL INTERFACE TIMING SPECIFICATIONS

t
SU:S
TO
t
SU:DI
t
SU:DI
t
SU:STO
t
B:FR
EE
S
C
L
SD
A
t
H
D
:D
I
/
t
H
D:
D
O
t
HIGH
t
L
OW
t
O
U
T
t
R
,
t
F
Start Condition
Data Transmission
Stop Condition
Electrical Specifications: Unless otherwise indicated, GND = Ground, T (Note 1).
= 1.7V to 3.6V VDD= 2.2V to 3.6V
V
DD
100 kHz
Parameters Sym Min Max
2-Wire I
Serial port frequency (Note 2, 4)f Low Clock (Note 2)t
High Clock t
Rise time
Fall time (Note 5)t Data in Setup time (Note 3) Data in Hold time (Note 6)t Data out Hold time (Note 4)t
Start Condition Setup time t
Start Condition Hold time t
Stop Condition Setup time t
Bus Idle/Free t
Time out t
Bus Capacitive load C
Note 1: All values referred to V
C Interface
SCL
LOW
t
SU:DAT
HD:DO
SU:STA
HD:STA
SU:STO
B-FREE
IL MAX
HIGH
R
F
HD:DI
OUT
and V
(Note 5)t
2: If t
LOW
> t
, the temperature sensor I2C interface will time out. A Repeat Start command is required for
OUT
10 100 10 400 10 1000 kHz
4700 — 1300 — 500 — ns
4000 — 600 — 260 — ns
— 1000 20 300 — 120 ns
20 300 20 300 — 120 ns
250 — 100 —50—ns
0— 0 —0—ns
200 900 200 900 0 350 ns
4700 — 600 — 260 — ns
4000 — 600 — 260 — ns
4000 — 600 — 260 — ns
4700 — 1300 — 500 — ns
25 35 25 35 25 35 ms
—— — 400 — 100 pf
IH MIN
levels.
communication.
3: This device can be used in a Standard-mode I
C-bus system, but the requirement t be met. This device does not stretch SCL Low period. It outputs the next data bit to the SDA line within t
RMAX
+ t
SU:DAT MIN
= 1000 ns + 250 ns = 1250 ns (according to the Standard-mode I2C-bus specification)
before the SCL line is released.
4: As a transmitter, the device provides internal minimum delay time t
region (min. 200 ns) of the falling edge of SCL t
to avoid unintended generation of Start or Stop
F MAX
conditions.
5: Characterized but not production tested. 6: As a receiver, SDA should not be sampled at the falling edge of SCL. SDA can transition t
SCL toggles Low.
= -40°C to +125°C, and CL = 80 pF
A
400 kHz 1000 KHz
Min Max Min Max Units
HD:DAT MIN
MCP98244
250 ns must
SU:DAT
to bridge the undefined
0 ns after
HD:DI

TIMING DIAGRAM

2012-2013 Microchip Technology Inc. DS22327C-page 5
MCP98244
-1.0
0.0
1.0
2.0
3.0
rature Accuracy (°C)
VDD= 1.7 V to 3.6 V
16 units
Spec. Limits
+Std. Dev.
verage
-3.0
-2.0
-40 -20 0 20 40 60 80 100 120
Tem p
e
TA(°C)
g
-Std. Dev.
25%
50%
75%
100%
Occurrences
TA= +85 °C V
DD
= 1.7 V - 3.6 V
16 units
0%
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
Temperature Accuracy (°C)
25%
50%
75%
100%
Occurrences
TA= +25 °C V
DD
= 1.7 V - 3.6 V
16 units
0%
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
Temperature Accuracy (°C)
150
200
250
300
I
DD
(µA)
EEPROM Write (Sensor in Shutdown Mode)
EEPROM Read (Sensor in Shutdown Mode)
50
100
-40 -20 0 20 40 60 80 100 120 T
A
(°C)
Sensor (EEPROM Inactive)
0.50
0.75
1.00
I
SHDN
(µA)
0.00
0.25
-40 -20 0 20 40 60 80 100 120
T
A
(°C )
1
1.2
1.4
1.6
1.8
V
POR
(V)
Falling V
DD
Rising V
DD
0.6
0.8
-40 -20 0 20 40 60 80 100 120 T
A
(°C)

2.0 TYPICAL PERFORMANCE CURVES

Note: The graphs and tables provided following this note are a statistical summary based on a limited number 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.
Note: Unless otherwise indicated, V
= -40°C to +125°C.
T
A
A
= 1.7V to 3.6V, GND = Ground, SDA/SCL pulled-up to VDD, and
DD

FIGURE 2-1: Temperature Accuracy.

FIGURE 2-4: Supply Current Vs.
Temperature.
FIGURE 2-2: Temperature Accuracy Histogram, T
FIGURE 2-3: Temperature Accuracy Histogram, T
DS22327C-page 6 2012-2013 Microchip Technology Inc.
= + 85 °C.
A
= + 105 °C.
A

FIGURE 2-5: Shutdown Current Vs. Temperature.

FIGURE 2-6: Power On Reset Threshold Voltage Vs. Temperature.

MCP98244
0.2
0.3
0.4
nt & SDA V
OL
(V)
SDA, IOL= 20 mA V
DD
= 2.2 V to 3.6 V
0
0.1
-40 -20 0 20 40 60 80 100 120
Ev
e
TA(°C)
Event, IOL= 3 mA
75
100
125
150
175
200
t
CONV
(ms)
0.0625 °C/LSb
0.125 °C/LSb
0
25
50
-40 -20 0 20 40 60 80 100 120 T
A
(°C)
0.25 °C/LSb
0.5 °C/LSb
30
40
50
SDA I
OL
(mA)
VOL= 0.6V
10
20
-40 -20 0 20 40 60 80 100 120 T
A
(°C)
-1.0
0.0
1.0
2.0
3.0
ized Temp. Error (°C)
VDD= 1.7 V V
DD
= 3.6 V
-3.0
-2.0
-40 -20 0 20 40 60 80 100 120
Norma
l
TA(°C)
30
35
Bus t
OUT
(ms)
25
-40 -20 0 20 40 60 80 100 120
I
2
C
TA(°C)
Note: Unless otherwise indicated, V
= -40°C to +125°C.
T
A
= 1.7V to 3.6V, GND = Ground, SDA/SCL pulled-up to VDD, and
DD

FIGURE 2-7: Event Output and SDA VOL Vs. Temperature.

FIGURE 2-10: Line Regulation: Change in Temperature Accuracy Vs. Change in V
DD
.

FIGURE 2-8: Temperature Conversion Rate Vs. Temperature.

FIGURE 2-9: SDA I
2012-2013 Microchip Technology Inc. DS22327C-page 7
Vs. Temperature.
OL

FIGURE 2-11: I2C Protocol Time-out Vs. Temperature.

MCP98244

3.0 PIN DESCRIPT ION

The descriptions of the pins are listed in Tab l e 3 -1 .

TABLE 3-1: PIN FUNCTION TABLES

MCP98244
TDFN
1 A0 Slave Address and EEPROM Software Write Protect High Voltage Input (V
2 A1 Slave Address
3 A2 Slave Address
4 GND Ground
5 SDA Serial Data Line
6 SCL Serial Clock Line
7 Event Temperature Alert Output
8V
9 EP Exposed Thermal Pad (EP); can be connected to GND.

3.1 Address Pins (A0, A1, A2)

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) are (A6, A5, A4, A3). This is shown in Table 3-2.

TABLE 3-2: MCP98244 ADDRESS BYTE

Device Address Code Slave
Sensor 0011 EEPROM 1010
EEPROM Write Protect
Note 1: User-selectable address is shown by X,
where X is 1 or 0 for V respectively.
2: The address pins are ignored for all Write
Protect commands.
Symbol Description
DD
Power 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 (SCL)

Address
A6 A5 A4 A3 A2 A1 A0
1X1X1
X
and GND,
DD
2—2—2
0110—
The SCL is a clock input pin. All communication 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 Temperature Alert, Open-Drain Output (Event)

The MCP98244 temperature Event output pin is an open-drain output. The device outputs a signal when the ambient temperature goes beyond the user-pro-
grammed temperature limit. (see Section 5.2.3 “Event
Output Configuration”).

3.6 Power Pin (VDD)

The A0 Address pin is a multi-function pin. This input pin is also used for high voltage input V EEPROM Software Write Protect feature, for more
information see Section 5.3.3 “Bank or page selec-
tion for EEPROM Read/write operation”.
All address pin have an internal pull-down resistors.
to enable the
HV

3.2 Ground Pin (GND)

The GND pin is the system ground pin.
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 can be connected to the same potential on the Printed Circuit Board (PCB). This provides better thermal conduction from the PCB to the die.
HV
)
DS22327C-page 8 2012-2013 Microchip Technology Inc.
MCP98244
123456789
SCL
SDA
0 0 1 1 A2 A1 A0
Start
Address Byte
Slave
Address
R/W
MCP98244 Response
Code
Address
A C K

4.0 SERIAL COMMUNICATION

4.1 2-Wire Standard Mode I2C™ Protocol-Compatible Interface

The MCP98244 serial clock input (SCL) and the bidirectional serial data line (SDA) form a 2-wire bidirectional Standard mode I
communication port (refer to the Input/Output Pin DC
Characteristics Table and Serial Interface Timing Specifications Table).
The following bus protocol has been defined:
TABLE 4-1: MCP98244 SERIAL BUS
PROTOCOL DESCRIPTIONS
Term Description
Master The device that controls the serial bus,
typically a microcontroller.
Slave The device addressed by the master,
such as the MCP98244.
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 MCP98244
registers.
ACK A receiver Acknowledges (ACK) the
reception of each byte by polling the bus.
NAK A receiver Not-Acknowledges (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 SCL remain high.
Data Valid SDA must remain stable before SCL
becomes high in order for a data bit to be considered valid. During normal data transfers, SDA only changes state while SCL is low.
C-compatible
This device supports the Receive Protocol. The register can be specified using the pointer for the initial read. Each repeated read or receive begins with a Start condition and address byte. The MCP98244 retains the previously selected register. Therefore, they output data from the previously-specified register (repeated 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 MCP98244 is a slave device and does not control other devices in the bus. Both master and slave devices can operate as either transmitter or receiver. However, the master device determines which mode is activated.
4.1.3 START/STOP CONDITION
A high-to-low transition of the SDA line (while SCL is high) is the Start condition. All data transfers must be preceded by a Start condition from the master. A low­to-high transition of the SDA line (while SCL is high) signifies a Stop condition.
If a Start or Stop condition is introduced during data transmission, the MCP98244 releases the bus. All data transfers are ended by a Stop condition from the master.
4.1.4 ADDRESS BYTE
Following the Start condition, the host must transmit an 8-bit address byte to the MCP98244. The address for the MCP98244 Temperature Sensor is ‘0011,A2,A1,A0’ in binary, where the A2, A1 and A0 bits are set externally by connecting the corresponding pins to V transmitted in the serial bit stream must match the selected address for the MCP98244 to respond with an ACK. Bit 8 in the address byte is a read/write bit. Setting this bit to ‘1’ commands a read operation, while ‘0’ commands a write operation (see Figure 4-1).
‘1’ or GND ‘0’. The 7-bit address
DD
4.1.1 DATA TRANSFER
Data transfers are initiated by a Start condition (START), followed by a 7-bit device address and a read/write bit. 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 t
This device does not support sequential register read/ write. Each register needs to be addressed using the Register Pointer.
2012-2013 Microchip Technology Inc. DS22327C-page 9
B-FREE

FIGURE 4-1: Device Addressing.

4.1.5 DATA VALID
.
After the Start condition, each bit of data in transmission needs to be settled for a time specified by t
SU-DATA
Serial Interface Timing Specifications table).
before SCL toggles from low-to-high (see
MCP98244
4.1.6 ACKNOWLEDGE (ACK/NAK)
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 acknowledging device pulls down the SDA line for t
SU-DATA
the master. SDA also needs to remain pulled down for t
H-DATA
During read, the master must signal an End-of-Data (EOD) to the slave by not generating an ACK bit (NAK) once the last bit has been clocked out of the slave. In this case, the slave will leave the data line released to enable the master to generate the Stop condition.
before the low-to-high transition of SCL from
after a high-to-low transition of SCL.
4.1.7 TIME OUT (T
If the SCL stays low or high for time specified by t the MCP98244 resets the serial interface. This dictates the minimum clock speed as indicated in the specification.
OUT
)
OUT
,
DS22327C-page 10 2012-2013 Microchip Technology Inc.
MCP98244
Clear Event
0.5°C/bit
0.25°C/bit
0.125°C/bit
0.0625°C/bit
Temperature
T
UPPER
T
LOWER
Configuration
 ADC
Band-Gap
Temperature
Sensor
Event Status
Output Control
Critical Event only
Event Polarity
Event Comp/Int
T
CRIT
Capability
Temp. Range
Accuracy
Output Feature
Register
Pointer
Critical Trip Lock
Alarm Win. Lock Bit
Shutdown
Hysteresis
Manufacturer ID
Resolution
Device ID/Rev
Selected Resolution
Standard I2C
Interface
A0
A1
A2
Event
SDA
SCL
V
DD
GND
I2C Bus Time-out
Accepts V
HV
Shutdown Status
MCP98244 Temperature Sensor
MCP98244 EEPROM
Memory Control
Logic
XDEC
HV Generator
Software write
Write Protect Circuitry
YDEC
SENSE AMP R/W CONTROL
protected area
(00h-7Fh)
(7Fh-FFh)
Software write protected area
(00h-7Fh)
(7Fh-FFh)
Software write protected area
Software write protected area

5.0 FUNCTIONAL DESCRIPTION

The MCP98244 temperature sensors consists of a band-gap type temperature sensor, a Delta-Sigma Analog-to-Digital Converter ( ADC), user-program-
mable registers and a 2-wire I serial interface. Figure 5-1 shows a block diagram of the register structure.
C protocol compatible

FIGURE 5-1: Functional Block Diagram.

2012-2013 Microchip Technology Inc. DS22327C-page 11
MCP98244

5.1 Registers

The MCP98244 device has several registers that are user-accessible. These registers include the Capability register, Configuration register, Event Temperature Upper-Boundary and Lower-Boundary Trip registers, Critical Temperature Trip register, Temperature register, Manufacturer Identification register and Device Identification register.
The Temperature register is read-only, used to access the ambient temperature data. The data is loaded in parallel to this register after t Temperature Upper-Boundary and Lower-Boundary Trip registers are read/writes. If the ambient temperature drifts beyond the user-specified limits, the MCP98244 device 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 Event
CONV
The Capability register is used to provide bits describing the MCP98244’s capability in measurement resolution, measurement range and device accuracy. The device Configuration register provides access to configure the MCP98244’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 MCP98244 using the serial interface. This is an 8-bit write-only pointer, and Register 5-1 describes the pointer assignment.
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’ bit 3-0 Pointer Bits:
0000 = Capability register 0001 = Configuration register (CONFIG) 0010 = Event Temperature Upper-Boundary Trip register (T 0011 = Event Temperature Lower-Boundary Trip register (T 0100 = Critical Temperature Trip register (T 0101 = Temperature register (T 0110 = Manufacturer ID register 0111 = Device ID/Revision register 1000 = TSE2004av Device ID and Vendor Silicon Revision Register 1001 = Resolution register 1XXX = Unused (The device will not acknowledge commands to other pointer locations.).
)
A
CRIT
)
UPPER
LOWER
)
)
DS22327C-page 12 2012-2013 Microchip Technology Inc.
MCP98244
TABLE 5-1: BIT ASSIGNMENT SUMMARY FOR ALL TEMPERATURE SENSOR REGISTERS
(SEE SECTION 5.4)
Register
Pointer
(Hex)
MSB/
LSB
76543210
0x00 MSB 00000000
LSB SHDN Status t
Range V
OUT
0x01 MSB 00000Hysteresis SHDN
LSB Crt Loc Win Loc Int Clr Evt Stat Evt Cnt Evt Sel Evt Pol Evt Mod
0x02 MSB 000SIGN 2
LSB 2
3
°C 22°C 21°C 20°C 2-1°C 2-2°C 0 0
0x03 MSB 000SIGN 2
3
LSB 2
°C 22°C 21°C 20°C 2-1°C 2-2°C 0 0
0x04 MSB 000SIGN 2
3
LSB 2
0x05 MSB T
LSB 2
°C 22°C 21°C 20°C 2-1°C 2-2°C 0 0
T
A
CRITTA
3
°C 22°C 21°C 20°C 2-1°C 2-2°C 2-3°C 2-4°C
T
UPPERTA
T
0x06 MSB 00000000
LSB 01010100
0x07 MSB 00100010
LSB 00000001
0x08 MSB 00100010
LSB 00000001
0x09 MSB 00000000
LSB 000000Resolution
HV
LOWER
Bit Assignment
Resolution Range Accuracy Event
7
°C 26°C 25°C 24°C
7
°C 26°C 25°C 24°C
7
°C 26°C 25°C 24°C
SIGN 27°C 26°C 25°C 24°C
2012-2013 Microchip Technology Inc. DS22327C-page 13
MCP98244
5.1.1 CAPABILITY REGISTER
This is a read-only register used to identify the temperature sensor capability. The device capability bit assignments are specified by TSE2004av, and this device is factory configured to meet the default conditions as described in Register 5-2 (these values can not be changed).
For example, the MCP98244 device is capable of providing temperature at 0.25°C resolution, measuring temperature below and above 0°C, providing ±1°C and ±2°C accuracy over the active and monitor temperature ranges (respectively) and providing user­programmable temperature event boundary trip limits.
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
R-1 R-1 R-1 R-0 R-1 R-1 R-1 R-1
SHDN Status t
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
Range V
OUT
HV
Resolution Meas. Range Accuracy Temp Alarm
bit 15-8 Unimplemented: Read as ‘0’ bit 7 Event output status during Shutdown (SHDN Status):
0 = Event output remains in previous state. If the output asserts before shutdown command, it
remains asserted during shutdown.
1 = Event output deasserts during shutdown. After shutdown, it takes t
output (power-up default)
bit 6 I
bit 5 High Voltage Input
bit 4-3 Resolution:
bit 2 Temperature Measurement Range (Meas. Range):
C Bus time-out (t
0 = Bus time-out range is 10 ms to 60 ms 1 = Bus time-out range is 25 ms to 35 ms (power-up default)
0 = Pin A0 does not accept High Voltage 1 = Pin A0 accepts High Voltage for the EEPROM Write Protect feature (power-up default)
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 5.2.4 “Temperature Resolution”)
0 =T 1 = The part can measure temperature below 0°C (power-up default)
0 (decimal) for temperature below 0°C
A
OUT
Range):
to re-assert the Event
CONV
DS22327C-page 14 2012-2013 Microchip Technology Inc.
MCP98244
SDA
A C K
0011
A
Capability Pointer
0000
A C K
S
2A1A0
12345678 12345678
SCL
0
Address Byte
A C K
0011
A
MSB Data
A C K
N A K
S P
2A1A0
12345678 12345678 12345678
Address Byte
LSB Data
R
MCP98244
MCP98244
MCP98244
Master
Master
W
SDA
SCL
000
00000
000 00001
111
REGISTER 5-2: CAPABILITY REGISTER (READ-ONLY) ADDRESS ‘0000 0000’b (CONTINUED)
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 A larm:
0 = No defined function (This bit will never be cleared or set to ‘0.’) 1 = The part has temperature boundary trip limits (T
temperature event output (JC 42.4 required feature)
UPPER/TLOWER/TCRIT
registers) and a
FIGURE 5-2: Timing Diagram for Reading the Capability Register (See Section 4.0 “Serial
Communication”).
2012-2013 Microchip Technology Inc. DS22327C-page 15
MCP98244
5.1.2 SENSOR CONFIGURATION REGISTER (CONFIG)
The MCP98244 device has a 16-bit Configuration reg­ister (CONFIG) that allows the user to set various func­tions 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, or temperature Event output enable/disable. In addition, the user can select the Event output condition (output set for T T
only), read Event output status and set Event
CRIT
UPPER
and T
temperature boundary or
LOWER
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 T T
LOWER
and T
to prevent an accidental rewrite.
CRIT
UPPER
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”).
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 (T
REGISTER 5-3: CONFIGURATION REGISTER (CONFIG) ADDRESS ‘0000 0001’b
)”. The Continuous
HYST
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 Unimplemented: Read as ‘0’ bit 10-9 T
UPPER
and T
Limit Hysteresis (T
LOWER
HYST
):
00 = 0°C (power-up default) 01 = 1.5°C 10 = 3.0°C 11 = 6.0°C
(Refer to Section 5.2.3 “Event Output Configuration”)
This bit can not be altered when either of the lock bits are set (bit 6 and bit 7).
This bit can be programmed in Shutdown mode.
bit 8 Shutdown Mode (SHDN):
0 = Continuous Conversion (power-up default) 1 = Shutdown (Low-Power mode)
In shutdown, all power-consuming activities are disabled, though all registers can be written to or read. Event output will deassert.
This bit cannot be set ‘1’ when either of the lock bits is set (bit 6 and bit 7). However, it can be cleared ‘0’ for Continuous Conversion while locked (Refer to Section5.2.1 “Shutdown Mode”).
DS22327C-page 16 2012-2013 Microchip Technology Inc.
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