JAJSAR0B March 2007 – October 2017 LM95214
PRODUCTION DATA.
The LM95214's TCRIT pins are active-low open-drain outputs and do not include internal pullup resistors. A high level will not be observed on these pins until pullup current is provided by some external source, typically a pullup resistor. Choice of resistor value depends on many system factors but, in general, the pullup resistor must be as large as possible without effecting the performance of the device receiving the signal. This will minimize any internal temperature reading errors due to internal heating of the LM95214. The maximum resistance of the pullup to provide a 2.1-V high level, based on LM95214 specification for High Level Output Current with the supply voltage at 3 V, is 82 kΩ (5%) or 88.7 kΩ (1%). The three TCRIT pins can each sink 6 mA of current and still ensured a Logic Low output voltage of 0.4 V. If all three pins are set at maximum current this will cause a power dissipation of 7.2 mW. This power dissipation combined with a thermal resistance of 77.8°C/W will cause the LM95214's junction temperature to rise approximately 0.6°C and thus cause the Local temperature reading to shift. This can only be cancelled out if the environment that the LM95214 is enclosed in has stable and controlled air flow over the LM95214, as airflow can cause the thermal resistance to change dramatically.