MCP9843 Datasheet, PDF (1/62 Pages) Microchip Technology – Memory Module Temperature Sensor w/ EEPROM for SPD

MCP9843/98243
Memory Module Temperature Sensor w/ EEPROM for SPD
Features
• Meets JEDEC Specification
- MCP9843 - JC42.4-TSE3000B3
Temperature Sensor
- MCP98243 --> JC42.4-TSE2002B3
Temperature Sensor with 2 Kbit Serial
EEPROM for Serial Presence Detect (SPD)
• 2-wire I²C™/SMBus Interface
• Available Packages:
- DFN-8, TDFN-8, UDFN-8, TSSOP-8
Temperature Sensor Features
• Temperature-to-Digital Converter
• Sensor Accuracy (Grade B):
- ±0.2°C/±1°C (typ./max.) → +75°C to +95°C
- ±0.5°C/±2°C (typ./max.) → +40°C to +125°C
- ±1°C/±3°C (typ./max.) → -20°C to +125°C
• Specified V_DD Range: 3.0V to 3.6V
• Operating Current: 200 µA (typical)
• Operating V_DD Range: 2.7V to 5.5V
Serial EEPROM Features (MCP98243)
• Specified V_DD Range: 1.8V to 5.5V
• Operating Current:
- Write → 1.1 mA (typical) for 3.5 ms (typical)
- Read → 100 µA (typical)
• Permanent and Reversible Software Write Protect
• Software Write Protection for the lower 1 Kbit
• Organized as 1 block of 256 x 8-bit (2 Kbit)
Typical Applications
• DIMM Modules for Servers, PCs, and Laptops
• General Purpose Temperature Datalog
DIMM MODULE
MCP9843/98243
Description
Microchip Technology Inc.’s MCP9843/98243 digital
temperature sensors convert temperature from -40°C
and +125°C to a digital word. These sensors meet
JEDEC Specification JC42.4-TSE3000B3 and
JC42.4-TSE2002B3 Memory Module Thermal Sensor
Component. It provides an accuracy of ±0.2°C/±1°C
(typical/maximum) from +75°C to +95°C. In addition,
MCP98243 has an internal 256 Byte EEPROM which
can be used to store memory module and vendor
information.
The MCP9843/98243 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 MCP9843/98243 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 MCP98243 EEPROM is designed specifically for
DRAM DIMMs (Dual In-line Memory Modules) Serial
Presence Detect (SPD). The lower 128 Bytes (address
0x00 to 0x7F) 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 0x80 to 0xFF) can be used for general
purpose data storage. These addresses are not write
protected.
This sensor has an industry standard 2-wire,
I²C compatible serial interface, allowing up to eight
devices to be controlled in a single serial bus.
Package Types
8-Pin 2x3 DFN/TDFN/UDFN * 8-Pin TSSOP
A0 1
8 V_DD
A0 ¹
A1 2 _EP 7 Event A1 ²
A2 3 ⁹ 6 SCL
A2 3
GND 4
5 SDA ^{GND 4}
8 ^VDD
7 ^Event
6 ^SCL
5 SDA
* Includes Exposed Thermal Pad (EP); see Table 3-1.
© 2009 Microchip Technology Inc.
DS22153C-page 1