A switching operation sensing device includes an input operation unit, an oscillator circuit, a frequency digital converter, and a touch-force detector circuit. The input operation unit, integrally formed with a housing, includes a first switch member and a second switch member disposed in different positions. The oscillator circuit is configured to generate a first oscillation signal based on varying capacitance when the first switch member is touched, and a second oscillation signal based on varying inductance when an input force is applied to the second switch member. The frequency digital converter is configured to convert the first oscillation signal to a first count value, and convert the second oscillation signal to a second count value. The touch-force detector circuit is configured to generate a first detection signal by detecting a touch input based on the first count value input from the frequency digital converter, and generate a second detection signal by detecting an input force based on the second count value.

A sensing device with a fingerprint sensor is provided. The sensing device includes a touch input pattern included in the fingerprint sensor, an oscillation circuit connected to the touch input pattern and configured to change a capacitance of the oscillation circuit when a touch occurrence is sensed by the touch input pattern and generate an oscillation signal based on the change in the capacitance, and an operation detection circuit configured to detect a touch occurrence based on a frequency included in the oscillation signal input from the oscillation circuit and generate a detection signal.

A switching operation sensing apparatus includes an input operation unit, an oscillation circuit, a frequency digital converter, and a touch detection circuit. The input operation unit includes a first switching member integrally formed with a housing. The oscillation circuit is configured to generate an oscillation signal having a resonant frequency, varying based on a capacitive change or an inductive change, depending on a touch input member in contact with the first switching member during an input operation. The frequency digital converter is configured to convert the oscillation signal into a count value. The touch detection circuit is configured to detect capacitive sensing and inductive sensing based on a slope change of the count value received from the frequency digital converter, and output corresponding touch detection signals of different levels based on the detection.

An arbitrary rate digital decimator filter (204) and associated method are disclosed for filtering a digital data stream with a plurality of cascaded power-of-two decimator stages (205, 207) connected to receive the digital data stream and to generate a first filtered digital signal which is provided to a fractional resampling stage (211) which generates a second filtered digital signal with delta-sigma modulator (310) and a limited integrator stage (320) connected to receive a first control (301) word and a feedback clock signal (305) with inserted or swallowed pulses which is generated by a clock generator in response to pulse commands generated by the limited integrator stage, wherein the limited integrator is configured to generate time shift commands (303) to a timing shift filter (340) which performs fractional interpolation on the first filtered digital signal to generate the second filtered digital signal.

A digital signal processor is designed to channelize an input signal, and includes a channelizer circuit and a plurality of tuning modules. The channelizer circuit is designed to receive an input signal having a first bandwidth and to channelize the input signal into a first set of channels each having a bandwidth smaller than the first bandwidth as a first output signal and to channelize the input signal into a second set of channels having a bandwidth smaller than the first bandwidth as a second output signal. The plurality of tuning modules are designed to receive one or more channels from the first output signal or the second output signal and to further downsample the one or more channels to a user-defined bandwidth at a user-defined center frequency. Each of the plurality of tuning modules include a plurality of FIR filter blocks and a memory having a plurality of FIR filter coefficients.

An analog-to-digital converter (ADC) includes a modulator configured to oversample an input signal generated from an output signal of a transducer; and a filter configured to perform a decimation operation on an output from the modulator and a frequency characteristics correction operation according to a filter control signal on the output from the modulator, wherein the frequency characteristics correction operation is performed to complement a frequency characteristics of the output signal of the transducer such that overall frequency characteristics of the transducer and the filter be flat in a signal band.

A switching operation sensing apparatus includes an input operation unit, an oscillation circuit, a frequency digital converter, and a touch detection circuit. The input operation unit includes a first switching member integrally formed with a housing. The oscillation circuit is configured to generate an oscillation signal having a resonant frequency, varying based on a capacitive change or an inductive change, depending on a touch input member in contact with the first switching member during an input operation. The frequency digital converter is configured to convert the oscillation signal into a count value. The touch detection circuit is configured to detect capacitive sensing and inductive sensing based on a slope change of the count value received from the frequency digital converter, and output corresponding touch detection signals of different levels based on the detection.

Aspect of the present disclosure provide for a circuit. In an example, the circuit comprises a multiplexer having a first input, a second input, a control input, and an output. The circuit further comprises a first register having an input coupled to the output of the multiplexer and an output. The circuit further comprises a second register having an input coupled to the output of the first register and an output. The circuit further comprises a subtractor having a first input coupled to the output of the multiplexer and a second input coupled to the output of the second register. The circuit further comprises a third register having an input coupled to the output of the subtractor and an output coupled to the first input of the multiplexer.

Aspect of the present disclosure provide for a circuit. In an example, the circuit comprises a multiplexer having a first input, a second input, a control input, and an output. The circuit further comprises a first register having an input coupled to the output of the multiplexer and an output. The circuit further comprises a second register having an input coupled to the output of the first register and an output. The circuit further comprises a subtractor having a first input coupled to the output of the multiplexer and a second input coupled to the output of the second register. The circuit further comprises a third register having an input coupled to the output of the subtractor and an output coupled to the first input of the multiplexer.

Most of the AC-DC converters have an analog control loop, which costs additional pins for the compensator, and there are limited options to change settings when, for example, the output voltage needs to change. This specification discloses systems and methods, where a delta-sigma ADC (analog-to-digital converter) is used to digitize the input voltage. The filter after the delta-sigma ADC can give a big delay, which reduces the phase margin of the control loop. To minimize the delay, this invention ensures that, when the setpoint is reached, the input of the delta-sigma modulator is in the middle of the input range. In some embodiments, a digital control loop can be implemented using a delta-sigma modulator together with a PI controller (proportional-integrator controller).