LM56

LM56 Dual Output Low Power Thermostat April 2000 LM56 Dual Output Low Power Thermostat General Description The LM56 is a precision low power thermostat. Two stable temperature trip points (VT1 and VT2) are generated by dividing down the LM56 1.250V bandgap voltage reference using 3 external resistors. The LM56 has two digital outputs. OUT1 goes LOW when the temperature exceeds T1 and goes HIGH when the the temperature goes below (T1–THYST). Similarly, OUT2 goes LOW when the temperature exceeds T2 and goes HIGH when the temperature goes below (T2–THYST). THYST is an internally set 5˚C typical hysteresis. The LM56 is available in an 8-lead Mini-SO8 surface mount package and an 8-lead small outline package. Features n n n n n n Digital outputs support TTL logic levels Internal temperature sensor 2 internal comparators with hysteresis Internal voltage reference Currently available in 8-pin SO plastic package Future availability in the 8-pin Mini-SO8 package Key Specifications n Power Supply Voltage n Power Supply Current n VREF n Hysteresis Temperature n Internal Temperature Sensor Output Voltage (+6.20 mV/˚C x T) +395 mV n Temperature Trip Point Accuracy: LM56BIM +25˚C +25˚C to +85˚C −40˚C to +125˚C LM56CIM 2.7V–10V 230 µA (max) 1.250V ± 1% (max) 5˚C Applications n n n n n n n n Microprocessor Thermal Management Appliances Portable Battery Powered 3.0V or 5V Systems Fan Control Industrial Process Control HVAC Systems Remote Temperature Sensing Electronic System Protection ...