摘要 |
On an electric cooker the sensor circuit (1) detects the presence of a pan (2) on each heater (F1-F4) and comprises a microcontroller (4) and a generator (6,7) that supply a high-frequency current (Ig) to a respective sensor loop (E1-E4) of each heater which generates a magnetic field, and two maximum and minimum reference signals (Vr0,Vr1) for all the heaters (F1-F4) obtained in the working temperature condition and a circuit (9-13) for measuring and evaluating the voltage (Vs) produced in each sensor loop, with a circuit part (11,11') for demodulation into low frequency of the measuring and reference signals (Vs,Vr0,Vr1), and their differential amplification (Vm,Vrr).
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