Abstract: An impedance sensor and an electronic apparatus using the same are provided. The impedance sensor includes an impedance-bridge circuit, a compensation circuit, and a signal processing circuit. The impedance-bridge circuit has an input side and an output side, and configured to generate a first impedance variation in response to a physical pressure. The compensation circuit is coupled to the input side of the impedance-bridge circuit in parallel, and configured to generate a second impedance variation in response to an environment temperature. The signal processing circuit respectively detects the first and the second impedance variations, and accordingly generates a first sensing signal indicating the first impedance variation and a second sensing signal indicating the second impedance variation, so as to compensate a temperature shift part of the first sensing signal by the second sensing signal and accordingly generate a pressure detection signal.

Abstract: An impedance sensor and an electronic apparatus using the same are provided. The impedance sensor includes an impedance-bridge circuit, a compensation circuit, and a signal processing circuit. The impedance-bridge circuit has an input side and an output side, and configured to generate a first impedance variation in response to a physical pressure. The compensation circuit is coupled to the input side of the impedance-bridge circuit in parallel, and configured to generate a second impedance variation in response to an environment temperature. The signal processing circuit respectively detects the first and the second impedance variations, and accordingly generates a first sensing signal indicating the first impedance variation and a second sensing signal indicating the second impedance variation, so as to compensate a temperature shift part of the first sensing signal by the second sensing signal and accordingly generate a pressure detection signal.

Abstract: A quantizer of a sigma-delta modulator includes a pulse width modulator (PWM), a converter and a voltage level tracing device. The PWM receives an input signal, and generates a PWM signal according to one or more sawtooth waves and one or more reference voltages. The converter is connected to the output of the PWM and digitizes the PWM signal to generate an output digital value. The voltage level tracing device is connected to the output of the converter, and receives the output digital value to generate a reference voltage adjustment value. The reference voltage adjustment value is transmitted to the PWM for adjusting the reference voltage, so as to change the next corresponding voltage level of the sawtooth wave to track the input signal.

Abstract: A switched-capacitor (SC) circuit relating to summing and integration algorithms is provided. The SC circuit submitted by the present invention benefits from better closed-loop bandwidth performance because of combining positive and negative feedback loops of a high gain amplifier. In addition, the SC circuit submitted by the present invention not only provides differential output signal obtained by a summing (or integration) algorithm of input voltage signals and reference voltage signals and forward drives such differential output signal to a next stage SC circuit, but also provides flexible and accurate coefficient design for every individual input and reference voltage signals in the said algorithm. Besides, if the circuit manner of alternate resetting is disabled or removed, the SC summing circuit submitted by the present invention can serve as an SC integration circuit.

Abstract: A quantizer of a sigma-delta modulator includes a pulse width modulator (PWM), a converter and a voltage level tracing device. The PWM receives an input signal, and generates a PWM signal according to one or more sawtooth waves and one or more reference voltages. The converter is connected to the output of the PWM and digitizes the PWM signal to generate an output digital value. The voltage level tracing device is connected to the output of the converter, and receives the output digital value to generate a reference voltage adjustment value. The reference voltage adjustment value is transmitted to the PWM for adjusting the reference voltage, so as to change the next corresponding voltage level of the sawtooth wave to track the input signal.