A first current source and a third current source are coupled at a first output node. A second current source and a fourth current source are coupled at a second output node. Control terminals of a first transistor and a second transistor are coupled to the second output node. Control terminals of a third transistor and a fourth transistor are coupled to the first output node. The first transistor and a fifth transistor are coupled in series between a power terminal and the first output node. A sixth transistor and the second transistor are coupled in series between the first output node and a ground terminal. The third transistor and a seventh transistor are coupled in series between the power terminal and the second output node. An eighth transistor and the fourth transistor are coupled in series between the second output node and the ground terminal.

Provided is a comparison circuit to which a negative voltage to be compared can be input directly. The comparison circuit includes a first input terminal, a second input terminal, a first output terminal, and a differential pair. The comparison circuit compares a negative voltage and a negative reference voltage and outputs a first output voltage from the first output terminal in response to the comparison result. The negative voltage is input to the first input terminal. A positive reference voltage is input to the second input terminal. The positive reference voltage is determined so that comparison is performed. The differential pair includes a first n-channel transistor and a second n-channel transistor each having a gate and a backgate. The first input terminal is electrically connected to the backgate of the first n-channel transistor. The second input terminal is electrically connected to the gate of the second n-channel transistor.

Disclosed is a dual clock signal to pulse-width modulated signal conversion circuit, comprising: a first counter, an input end of which inputs a first clock signal, and an output end of which outputs a divided signal; an edge reset circuit, an input end of which inputs the divided signal, the output end of which outputs a first reset pulse signal and a second reset pulse signal, the first reset pulse signal being configured for resetting a second counter, and the second reset pulse signal being configured for resetting a third counter; a second counter, an input end of which inputs the second clock signal and the first reset pulse signal, and an output end of which outputs the first pulse-width modulated signal; a third counter, an input end of which inputs the second clock signal and the second reset pulse signal, and an output end of which outputs the second pulse-width modulated signal; a logic processing circuit, an input end of which inputs the first pulse-width modulated signal and the second pulse-width modulated signal, and an output end of which outputs a pulse-width modulated signal PWM_OUT. The disclosure offers high precision, system stability, and good anti-interference.

Circuits and methods for reducing and cancelling out kickback noise are disclosed. In one example, a circuit for a comparator is disclosed. The circuit includes: a first transistor group, a second transistor group, and a first switch. The first transistor group comprises a first transistor having a drain coupled to a first node, and a second transistor having a source coupled to the first node. Gates of the first transistor and the second transistor are coupled together to a first input of the comparator. The second transistor group comprises a third transistor having a drain coupled to a second node, and a fourth transistor having a source coupled to the second node. Gates of the third transistor and the fourth transistor are coupled together to a second input of the comparator. The first switch is connected to and between the first node and the second node.

The present disclosure provides a substrate-enhanced comparator and electronic device, the comparator including: a cross-coupled latch, for connecting input signals to the gate of a cross-coupled MOS transistor to form a first input of the latch; output buffers, connected to the cross-coupled latch for amplifying output signals of the latch; AC couplers, connected to the output buffers for receiving and amplifying the output signals of the latch, coupling the output signals to substrates of the cross-coupled MOS transistors to form second inputs of the latch. The cross-coupled latch is also for output signal regenerative latching based on input signals sampled at the first inputs and input signals sampled at the second inputs. The present disclosure introduces additional substrate inputs to the cross-coupled structure of the conventional latch as the second inputs of the latch.

An on-die voltage regulator (VR) is provided that can deliver much higher conversion efficiency than the traditional solution (e.g., FIVR, LDO) during the standby mode of a system-on-chip (SOC), and it can save the power consumption significantly, during the connected standby mode. The VR operates as a switched capacitor VR under the low load current condition that is common during the standby mode of the SOC, while it automatically switches to the digital linear VR operation to handle a sudden high load current condition at the exit from the standby condition. A digital proportional-integral-derivative (PID) controller or a digital proportional-derivative-averaging (PDA) controller is used to achieve a very low power operation with stability and robustness. As such, the hybrid VR achieves much higher conversion efficiency than the linear voltage regulator (LVR) for low load current condition (e.g., lower than 500 mA).

A comparing device includes a first current generating circuit arranged to selectively generate a first current and a second current different from the first current, according to a first control signal. The comparing device also includes a comparing circuit having a common node coupled to the first current generating circuit for comparing a first input signal and a second input signal to generate an output signal according to the first current, the second current, and a second control signal. The second control signal and the first control signal are in-phase with each other.

The present invention provides a lead-on detection circuitry of a biopotential acquisition system. The lead-on detection circuitry includes an input terminal, a duty-cycle controller, a transmitting signal generator and a mixer-based receiver. The duty-cycle controller is configured to generate a first clock signal. The transmitting signal generator is configured to generate a transmitting signal to the input terminal according to the first clock signal. The mixer-based receiver is configured to perform a mixing operation based on the first clock signal and the transmitting signal to generate an output signal, wherein the output signal indicates if an electrode of the biopotential acquisition system is in contact with a human body, and the electrode is coupled to the input terminal.

A comparator includes: a first stage circuit, configured to receive a voltage signal to be compared and a reference voltage signal Vref, and to generate and output a first amplifying signal and a second amplifying signal based on the voltage signal to be compared and the reference voltage signal Vref; a second stage circuit, connected with the first stage circuit, configured to generate and latch a first output signal and a second output signal based on the first amplifying signal and the second amplifying signal; wherein the first stage circuit and/or the second stage circuit include(s) a first pair of cross-coupled transistors.

A circuit includes a transconductance stage having first and second outputs. The circuit also includes a comparator having first and second inputs. The first input is coupled to the first output, and the second input is coupled to the second output. The comparator includes first through fifth transistors and a pair of cross-coupled transistors. The pair of cross-coupled transistors is coupled to the second current terminals of the first and second transistors. The second current terminal of the third transistor is coupled to the second current terminal of the first transistor, and the first current terminals of the first, second, and third transistors are coupled together. The second current terminals of the fourth and fifth transistors are coupled together and to the control input of the third transistor.