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LM75AD temperature sensor

This feature is included only in tasmota-sensors.bin

Otherwise you must compile your build. Add the following to user_config_override.h:

#ifndef USE_LM75AD 
#define USE_LM75AD      // [I2cDriver20] Enable LM75AD sensor (I2C addresses 0x48 - 0x4F) (+0k5 code)
#endif

The LM75AD is an I2C temperature sensor that converts temperature directly to digital signals from -55°C to +125°C and achieves an accuracy of 0.125°C

Some features of the LM75A chip not implemented in this driver:
- Programmable temperature threshold and hysteresis set points - Stand-alone operation as thermostat at power-up

LM75A Datasheet

Configuration~

Wiring~

LM75AD ESP8266
VCC 3.3V
GND GND
SDA GPIOx
SCL GPIOy
OS not used

The driver currently only allows the use of a single LM75AD sensor on any of the addresses configurable through pins A0, A1 and A2. These are conveniently broken out on the breakout board either as pins or as solderable joints as can be seen on the example breakout board.

These pins need to be tied down to either GND or VCC (3.3V) and the resulting I2C address will be set during power-up according to the table: Address MAP

Tasmota Settings~

In the Configuration -> Configure Module page assign:

  1. GPIOx to I2C SDA (6)
  2. GPIOy to I2C SCL (5)

After a reboot the driver will detect LM75AD automatically and display Temperature.

Commands~

TempOffset can be used for calibrating the measured temperature. This setting affects all temperature sensors on the device.

Breakout Boards~

Can also be used standalone if soldered to a board given the diagram is used

Circuit

R1 and R2 are pull-up resistors which are required by the I2C bus to operate properly. If you have other I2C sensors with pull-up resistors connected to the same I2C bus it's probably not necessary to have them.