LM77 temperature sensor

LM77 temperature sensor

Hello World

Import programmbed_HP03SA_LM77

Test program for HP03SA pressure and altitude sensor and for LM77 temperature sensor. Both devices use and I2C interface.


Import libraryLM77

LM77 Temperature sensor with I2C interface. Provides temperature in celsius and fahrenheit. The device also supports temperature alerts.





The LM77 is a digital temperature sensor and thermal window comparator with an I2C Serial Bus interface. The open-drain Interrupt (INT) output becomes active whenever temperature goes outside a programmable window, while a separate Critical Temperature Alarm (T_CRIT_A) output becomes active when the temperature exceeds a programmable critical limit. The INT output can operate in either a comparator or event mode, while the T_CRIT_A output operates in comparator mode only. The host can program both the upper and lower limits of the window as well as the critical temperature limit. Programmable hysterisis as well as a fault queue are available to minimize false tripping. Two pins (A0, A1) are available for address selection. The sensor powers up with default thresholds of 2°C THYST, 10°C TLOW, 64°C THIGH, and 80°C T_CRIT.

The figure below shows a blockdiagram of the LM77.


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