Maxim 公司的LM75是帶Delta-Sigma ADC和數字超溫檢測器的溫度傳感器，I2C總線接口，漏極開路輸出，工作電壓3.0V到5.5V，典型工作電流200uA，關斷電流4uA，廣泛應用于熱系統管理，熱保護，測試設備，計算機和辦公設備。本文介紹了LM75的主要特性，功能方框圖，以及風扇控制電路，I2C 控制的溫度傳感器應用電路和帶聲音告警的溫度傳感器應用電路。
The LM75 temperature sensor includes a delta-sigma analog-to-digital converter, and a digital overtemperature detector. The host can query the LM75 through its I2C interface to read temperature at any time. The open-drain overtemperature output (OS) sinks current when the programmable temperature limit is exceeded.
The OS output operates in either of two modes, comparator or interrupt. The host controls the temperature at which the alarm is asserted (TOS) and the hysteresis temperature below which the alarm condition is not valid (THYST). Also, the LM75’s TOS and THYST registers can be read by the host. The address of the LM75 is set with three pins to allow multiple devices to work on the same bus. Power-up is in comparator mode, with defaults of TOS = +80°C and THYST = +75°C. The 3.0V to 5.5V supply voltage range, low supply current, and I2C interface make the LM75 ideal for many applications in thermal management and protection.
LM75主要特性：
_ SO (SOP) and μMAX (μSOP) Packages
_ I2C Bus Interface
_ Separate Open-Drain OS Output Operates as Interrupt or Comparator/Thermostat Input
_ Register Readback Capability
_ Power-Up Defaults Permit Stand-Alone Operation as a Thermostat
_ 3.0V to 5.5V Supply Voltage
_ Low Operating Supply Current 250μA (typ), 1mA (max)
_ 4μA (typ) Shutdown Mode Minimizes Power Consumption
_ Up to Eight LM75s Can Be Connected to a Single Bus
_ Pin- and/or Register-Compatible with Improved-Performance Maxim Sensors Including MAX7500, MAX6625, MAX6626, DS75LV, and DS7505
LM75應用：
Thermal System Management
Thermal Protection
Test Equipment
Computers and Office Electronics
圖1 LM75功能方框圖
圖2 采用LM75的風扇控制
圖3 I2C 控制的溫度傳感器
詳情請見：http://datasheets.maxim-ic.com/en/ds/LM75.pdf