Abstract: A method and an electronic readout circuit for measuring a capacitance of a MEMS sensor are disclosed. In one aspect, the readout circuit includes: an input stage for receiving a first signal from the sensor and for presenting a second signal; a charge amplifier stage for amplifying and integrating the second signal; and a control logic for controlling the readout circuit according to a predefined timing relation synchronized to actuation voltages applied to the sensor for generating the first signal. The readout circuit may further includes a first switching unit for applying a first reference voltage to the sensor and a second switching unit for applying the second signal to the charge amplifier stage, wherein the first and the second switching units are controlled according to the predefined timing relation such that a plurality of the second signals are accumulated.

Abstract: A method and an electronic readout circuit for measuring a capacitance of a MEMS sensor are disclosed. In one aspect, the readout circuit includes: an input stage for receiving a first signal from the sensor and for presenting a second signal; a charge amplifier stage for amplifying and integrating the second signal; and a control logic for controlling the readout circuit according to a predefined timing relation synchronized to actuation voltages applied to the sensor for generating the first signal. The readout circuit may further includes a first switching unit for applying a first reference voltage to the sensor and a second switching unit for applying the second signal to the charge amplifier stage, wherein the first and the second switching units are controlled according to the predefined timing relation such that a plurality of the second signals are accumulated.

Abstract: An analogue-to-digital (A/D) converter converts an analogue input signal to a digital code representing the analogue input signal. The A/D converter includes a comparator for comparing the input signal with a reference signal, a search logic block for determining the digital code, and an A/D converter arranged for receiving input from the search logic block and for providing the reference signal to be applied to the comparator. At least a first portion of the A/D converter is implemented with equal capacitors and may be controlled by a thermometer coded signal. Additionally, the A/D converter may include a second portion implemented using binary weighted capacitors controlled by a thermometer coded or binary coded signal. The A/D converter may also include a plurality of A/D converters coupled by an analogue addition circuit or a weighted summing amplifier.

Abstract: The present disclosure is related to an analogue-to-digital (A/D) converter (1) for converting an input signal (Vin) to a digital code representing said input signal. The A/D converter comprises a comparator (3) for comparing the input signal with a reference signal (VA), a search logic block (4) for determining the digital code and a digital-to-analogue converter (5) arranged for receiving input from the search logic block and for providing the reference signal to be applied to the comparator. The digital-to-analogue converter comprises at least a first portion implemented with equal capacitors (20). The ADC optionally further comprises a second portion implemented with binary weighted capacitors. The first portion is arranged for being controlled by a thermometer coded signal. The converter avoids charging-discharging of large capacitors during the search and therefore reduces the lost energy.