A fingerprint recognizing sensor with fast recognition, including: a substrate, a conductive plate, a passivation layer, a charging capacitor, a switch group, and an analog to digital (AD) converter; the conductive plate being arranged on the substrate; the passivation layer being arranged on the conductive pad for receiving a finger to detect a fingerprint; the switch group including a first switch and a second switch; the first switch controlling an input voltage to charge the charging capacitor; two ends of the second switch being electrically connected to the conductive plate and the first switch as well as the charging capacitor, respectively; the AD converter being electrically connected to the charging capacitor; where the second switch controls the charging capacitor to perform charge sharing for multiple times; and the AD converter outputs a fingerprint recognizing signal according to a residual voltage after the charge sharing.

The present disclosure provides a DC power supply system, comprising: a first power supply circuit and a second power supply circuit, each power supply circuit comprises a phase-shifting transformer and an AC-DC conversion circuit; and a bidirectional electronic switch electrically coupled between the output end of the first power supply circuit and the output end of the second power supply circuit, wherein the bidirectional electronic switch is configured to transmit power between the output end of the first power supply circuit and the output end of the second power supply circuit depend on the voltage difference of the two output voltages.

A circuit for receiving serial data. In some embodiments, the circuit has an input for receiving an analog input signal, and includes a first sampler for sampling the analog input signal relative to a first reference voltage, a second sampler for sampling the analog input signal relative to a second reference voltage, and a reference voltage control circuit. The second reference voltage may have a sign opposite to that of the first reference voltage; and the reference voltage control circuit may be configured to adjust the first reference voltage or the second reference voltage, based on a first sample of the analog input signal, the first sample having been taken at a sampling time corresponding to a one bit, in the serial data, preceded by a one bit and followed by a one bit.

A circuit configured to sense an input analog signal generated by a sensor at a first frequency and to generate an output digital signal indicative of the sensed input analog signal. The circuit includes a conditioning circuit, an ADC, a feedback circuit, and a low-pass filter. The conditioning circuit is configured to receive the input analog signal and to generate a conditioned analog signal. The ADC is configured to provide a converted digital signal based on the conditioned analog signal. The feedback circuit includes a band-pass filter configured to selectively detect a periodic signal at a second frequency higher than the first frequency and to act on the conditioning circuit to counter variations of the periodic signal at the second frequency. The low-pass filter is configured to filter out the periodic signal from the converted digital signal to generate the output digital signal.

Aspects of the present disclosure provide for circuit. In at least some examples, the circuit includes a controller, a current source, a switch, and a digital-to-analog converter (DAC). The controller includes an analog-to-digital converter (ADC) having an input and an output, a first register, and a second register coupled to the output of the ADC. The switch is coupled between an output of the current source and a first node and has a control terminal coupled to the controller. The first node is coupled to the input of the ADC and is configured to couple to a resistor. The DAC has an input coupled to the controller and an output configured to couple to a battery.

Described are apparatus and methods for analog to digital converter (ADC) with factoring and background clock calibration. An apparatus includes an ADC configured to sample and convert differential input signals using a reference clock to obtain a defined number of samples during a first state in an acquisition clock cycle, and a finite state machine circuit configured to obtain the defined number of samples from the ADC using a clock based on the reference clock, factor the defined number of samples based on at least a common mode offset associated with the ADC, and send offset factored output to a controller.

A transceiver includes a medium dependent interface configured to provide AC (alternate current) coupling between a first node and a second node; a broadband matching network 120 configured to couple the second node to a third node; a programmable gain amplifier configured to receive a third voltage signal at the third node and output a fourth voltage signal in accordance with a first logical signal; an analog-to-digital converter configured to receive the fourth voltage signal and output a first data in accordance with the first logical signal and a first clock; and a digital-to-analog converter configured to receive a second data and output a first current signal to the third node in accordance with a second logical signal and a second clock, wherein: the first logical signal and the second logical signal are asserted alternately.

The disclosure belongs to the field of integrated circuits, and is used for reducing an area overhead and a power consumption of a pipelined analog-to-digital converter. Each stage of the pipelined analog-to-digital converter according to the disclosure comprises an analogue-to-digital converter, a digital-to-analog converter, a subtractor and an amplifier. According to the disclosure, an amplification time of the pipelined ADC is used for extra quantization, and a number of bits of each ADC is reduced on the premise of not increasing a number of stages of the pipelined ADC, so that a scale of each circuit is greatly reduced, and the power consumption and the area overhead are reduced.

A flyback converter is provided that detects a load-transient-produced increase in the output current to more quickly detect and respond to the load transient.

An image sensor may contain an array of imaging pixels. Each pixel column outputs signals that are read out using a successive approximation register (SAR) analog-to-digital converter (ADC). The SAR ADC may include at least first and second input sampling capacitors, a comparator, a capacitive digital-to-analog converter (CDAC), and associated control circuitry. If desired, the SAR ADC may include a bank of more than two input sampling capacitors alternating between sampling and conversion. The first capacitor may be used to sample an input signal while conversion for the second capacitor is taking place. Prior to conversion, an input voltage of the comparator and an output voltage of the CDAC may be initialized. During conversion of the signal on the first capacitor, the first capacitor is embedded within the SAR ADC feedback loop to prevent charge sharing between the input sampling capacitor and the CDAC, thereby mitigating potential capacitor mismatch issues.