Methods and apparatus include and amplifier circuit and a first capacitor branch including a first plurality of capacitors. The first capacitor branch couples to an input signal and to an input of the amplifier circuit. A second capacitor branch includes a second plurality of capacitors. The second capacitor branch couples to the input of the amplifier circuit and to an output of the amplifier circuit.

Methods and apparatus include and amplifier circuit and a first capacitor branch including a first plurality of capacitors. The first capacitor branch couples to an input signal and to an input of the amplifier circuit. A second capacitor branch includes a second plurality of capacitors. The second capacitor branch couples to the input of the amplifier circuit and to an output of the amplifier circuit.

A fingerprint sensing circuit, system, and method is disclosed. The fingerprint sensor maybe include a plurality of inputs coupled to a plurality of fingerprint sensing electrodes and to an analog front end. The analog front end may be configured to generate at least one digital value in response to a capacitance of at least one of the plurality of fingerprint sensing electrodes. Additionally, the analog front end may include a quadrature demodulation circuit to generate at least one demodulated value for processing by a channel engine. The channel engine may generate a capacitance result value that is based, in part, on the demodulated value and is stored in a memory.

A circuit includes an integrator circuit. The integrator circuit includes: an operational amplifier having an input terminal and an output terminal; a trimmable component having a first terminal, a second terminal, and a control terminal, the first terminal of the trimmable component coupled to the input terminal, and the second terminal of the trimmable component coupled to the output terminal; and a calibration control circuit having a first terminal and a second terminal, the first terminal of the calibration control circuit coupled to the output terminal, and the second terminal of the calibration control circuit coupled to the control terminal of the trimmable component.

The disclosure relates to an integrator circuit (300) for a Sigma-Delta, , modulator, the integrator circuit (300) comprising an integrator module (310) comprising a differential amplifier (301), a sampling module (320) comprising sampling capacitors (CS1p, CS2p, CS1n, CS2n) and a reference module (330) comprising first and second pluralities of reference capacitors (331.sub.1-x, 332.sub.1-x) connected between respective first and second lines (308, 309) and first and second pluralities of reference switches (331.sub.1-x, 332.sub.1-x) for connecting each of the reference capacitors (331.sub.1-x, 332.sub.1-x) to either a first reference terminal (324) or a second reference terminal (325). In operation, the reference switches (331.sub.1-x, 332.sub.1-x) are switched according to a thermometrically coded quantizer signal.