摘要 |
An electronic control circuit for a bridge resistance circuit (10) of a transducer (20) has a switchable source of constant magnitude current (22) to direct current pulses of constant amplitude through the bridge circuit. A temperature setpoint detector (24) generates a temperature signal (TA) to a control logic circuit (26) when the circuit attains a predetermined temperature. The control logic circuit periodically turns on the current and directs a sample and hold network (32) to read the transducer output when the predetermined temperature is reached by enabling a gate (30). The control logic circuit turns off the current by applying a signal to the source of current after a reading of transducer output is taken. The current through the transducer develops its output, heats up the transducer and generates the temperature signal.
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