MCP9805

`Meets JEDEC Standard JC42.4 for Mobile Platform Memory Module Thermal Sensor
`Temperature-to-Digital Converter
`Accuracy with 0.25/LSb Resolution
-±1 (max.) from +75 to +9
-±2 (max.) from +40 to +12
-±3 (max.) from -20 to +12
`Programmable Temperature Monitor Boundary
`Critical Temperature Output
`Operating Voltage Range: 3.0V to 3.6V
`2-wire Interface: SMBus/Standard mode I<sup>2</sup>C<sup>TM</sup> Compatible
`Operating Current: 200A (typ.
`Shutdown Current: 0.1A (typ.
`Available Packages: 2x3 DFN-8, TSSOP-8

Absolute Maximum Ratings *
V_DD .................................................................. 6.0V
Voltage at all Input/Output pins....GND- 0.3V to 5.5
Storage temperature.........................-65 to +150
Ambient temp. with power applied....-40 to +125
Junction Temperature (T_J)...............................+150
ESD protection on all pins (HBM:MM).........(4kV:200V)
Latch-Up Current at each pin........................ ±200m

* Notice: Stresses above those listed under 'Maximu ratings' may cause permanent damage to the device. This isa 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.

Microchip Technology Inc's MCP9805 digital tempera ture sensor converts temperatures between -40 an +125 to a digital word. This sensor is designed t meet the JEDEC standard JC42.4 for Mobile Platform Memory Module Thermal Sensor. This device provides an accuracy of ±1 (max.) from a temperature ran of +75 to +95 (active range) and ±2 (max.) +40 to +125 (monitor range) as defined in t JEDEC standard.

The MCP9805 comes with user-programmable registers that provide flexibility for DIMM temperature-sensing pplications. The registers allow user-selectable settings such as Shutdown or Low-Power modes and the specification of tempera- ture event and critical output boundaries. When the temperature changes beyond the specified boundary limits, the MCP9805 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.

This sensor has a 2-wire industry-standard SMBus and Standard mode I²C compatible (100kHz bus clock) serial interface protocol, allowing up to eight sen- sors to be controlled in a single serial bus. These fea- tures make the MCP9805 ideal for sophisticated multi-zone temperature-monitoring applications.