Title :
A temperature sensor with single resistor set-point programming
Author_Institution :
Analog Devices Inc., Wilmington, MA, USA
Abstract :
Temperature set-point switches are used in applications from electric irons to industrial controls. A monolithic circuit combining simplicity with user programmability is ideal for many PC board applications. The circuit has an output which switches low when the die reaches a temperature set by a user selected resistor. The circuit uses laser-wafer-trimmed thin-film resistors to calibrate the resistor vs. temperature relationship to a simple formula. To determine its operating temperature, the circuit compares a PTAT voltage, generated by a current density ratio, to a CTAT voltage, derived from a base-emitter voltage. The circuit configuration allows a single temperature non-interactive trim for each of these voltages, to match the predetermined resistance vs. temperature characteristics.
Keywords :
application specific integrated circuits; electric sensing devices; temperature sensors; thin film resistors; CTAT voltage; PTAT voltage; laser-wafer-trimmed thin-film resistors; monolithic circuit; set-point programming; set-point switches; single temperature noninteractive trim; temperature sensor; Equations; Industrial control; Iron; Resistors; Switches; Switching circuits; Temperature dependence; Temperature sensors; Thin film circuits; Voltage;
Conference_Titel :
Solid-State Circuits Conference, 1996. Digest of Technical Papers. 42nd ISSCC., 1996 IEEE International
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-3136-2
DOI :
10.1109/ISSCC.1996.488642
