The LM89 is an 11-bit digital temperature sensor with a 2-wire System Management Bus (SMBus) serial interface. The LM89 accurately measures its own temperature as well as the temperature of an external device, such as processor thermal diode or diode-connected transistor such as the 2N3904. The temperature of any ASIC, GPU, FPGA or MCU can be accurately determined using the LM89 as long as a dedicated diode (semiconductor junction) is available on the target die. The LM89 has an Offset register to allow calibration for different nonideality factors without requiring software management.
Activation of the ALERT occurs when any temperature goes outside a preprogrammed window set by the HIGH and LOW limit registers or exceeds the T_CRIT limit. Activation of the T_CRIT_A occurs when any temperature exceeds the T_CRIT programmed limit.
The LM89 is pin and register compatible with the LM86, LM90, LM99, On Semiconductor ADM1032 and Maxim MAX6657/8.
The LM89C and the LM89-1C have the same functions but different SMBus slave addresses, allowing multiple LM89's on a bus. LM89-1D’s default local T_CRIT temperature limit is 105°C; all other versions are 85°C.
| Top documentation | Type | Title | Format options | Date |
|---|---|---|---|---|
| * | Data sheet | LM89 ±0.75°C Accurate, Remote Diode And Local Digital Temperature Sensor With Two-Wire Interface datasheet (Rev. D) | PDF | HTML | Jun 23, 2014 |
| User guide | LM86, LM89, LM89-1, LM90, LM99, LM99-1 Evaluation Board User’s Guide | Feb 29, 2012 |
For additional terms or required resources, click any title below to view the detail page where available.
The Linux driver supports the LM90 series of Remote and Local Temp Sensors. The Linux driver supports communication through the I2C bus and interfaces with the Hardware Monitoring sub-system.
Available in Linux Main line: Yes
Available through git.ti.com: N/A
SensorEval
SensorEval software supports the latest TI temperature sensor and hardware monitor evaluation boards via USB interface. It also allows access to sensors mounted directly on motherboards that support Intel chip sets.
| Package | Pins | CAD symbols, footprints & 3D models |
|---|---|---|
| VSSOP (DGK) | 8 | Ultra Librarian |
| SOIC (D) | 8 | Ultra Librarian |
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