The LM95245 is an 11-bit digital temperature sensor with a 2-wire System Management Bus (SMBus) interface and TruTherm technology that can monitor the temperature of a remote diode as well as its own temperature. The LM95245 can be used to very accurately monitor the temperature of external devices such as microprocessors. TruTherm technology allows the LM95245 to precisely monitor thermal diodes found in 90 nm and smaller geometry processes. The LM95245 is specifically targeted for Intel processors on 45nm process. LM95245 reports temperature in two different formats for +127.875°C/-128°C range and 0°C/255°C range. The LM95245 T_CRIT\ and OS\ outputs are asserted when either unmasked channel exceeds its programmed limit and can be used to shutdown the system, to turn on the system fans, or as a microcontroller interrupt function. The current status of the T_CRIT\ and OS\ pins can be read back from the status registers via the SMBus interface. All limits have a shared programmable hysteresis register.
The remote temperature channel of the LM95245 has a programmable digital filter. The LM95245 is targeted for a typical Intel® processor on a 45 nm, 65 nm or 90nm process, and has an offset register for maximum flexibility and best accuracy.
The LM95245 has a three-level address pin to connect up to 3 devices to the same SMBus master, that is shared with the OS\ output. The LM95245 has a programmable conversion rate register and a standby mode to save power. One conversion can be triggered in standby mode by writing to the one-shot register.
Remote and Local Temperature Channels
Targeted for Intel 45nm Processor Diodes
Two Formats: −128°C to +127.875°C and 0°C to 255.875°C
Digital Filter for Remote Channel
Programmable TCRIT and OS Thresholds
Programmable Shared Hysteresis Register
Diode Fault Detection
Mask, Offset, and Status Registers
SMBus 2.0 Compatible Interface, Supports TIMEOUT
Programmable Conversion Rate for Best Power Consumption
Three-Level Address Pin
Standby Mode One-Shot Conversion Control
Pin-for-Pin Compatible With the LM95235 and LM86, LM89, LM99
8-Pin VSSOP and SOIC Packages
Supply Voltage 3.0 to 3.6 V
Supply Current, Conv. Rate = 1 Hz 350 µA (typ)
Remote Diode Temperature Accuracy
TA = 25°C to 85°C; TD = 50°C to 105°C, ±0.75 °C (max)
TA = 25°C to 85°C; TD = 40°C to 125°C, ±1.5 °C (max)