LM94021 Datasheet | National Semiconductor

Description The LM94021 is a precision analog output CMOS integrated-circuit temperature sensor that operates at a supply voltage as low as 1.5V. While operating over the wide temperature range of - 50˚C to +150˚C, the LM94021 delivers an output voltage that is inversely porportional to measured temperature. The LM94021’s low supply current makes it ideal for battery-powered systems as well as general temperature sensing applications. Two logic inputs, Gain Select 1 (GS1) and Gain Select 0 (GS0), select the gain of the temperature-to-voltage output transfer function. Four slopes are selectable: - 5.5 m V/˚C, - 8.2 m V/˚C, - 10.9 m V/˚C, and - 13.6 m V/˚C. In the lowest gain configuration (GS1 and GS0 both tied low), the LM94021 can operate with a 1.5V supply while measuring temperature over the full - 50˚C to +150˚C operating range. Tying both inputs high causes the transfer function to have the largest gain of - 13.6 m V/˚C for maximum temperature sensitivity. The gain-select inputs can be tied directly to VDD or Ground without any pull-up or pull-down resistors, reducing ponent count and board area. These inputs can also be driven by logic signals allowing the system to optimize the gain during operation or system diagnostics. n Disk Drives n Games n Appliances Features n Low 1.5V operation n Four selectable gains n Very accurate over wide temperature range of - 50˚C to +150˚C n Low quiescent current n Output is short-circuit protected n Extremely small SC70 package n Footprint patible with the industry-standard LM20 temperature sensor Key Specifications j Supply Voltage j Supply Current j Temperature 1.5V to 5.5V 9 µA (typ) 20˚C to 40˚C -50˚C to 70˚C -50˚C to 90˚C -50˚C to 150˚C Accuracy Applications n n n n Cell phones Wireless Transceivers Battery Management Automotive ± 1.5˚C ± 1.8˚C ± 2.1˚C ± 2.7˚C - 50˚C to 150˚C j Operating Temperature Connection Diagram SC70-5 Typical Transfer Characteristic Output Voltage vs Temperature Top View See NS Package...