The present invention provides a power supply circuit with an adjustable channel switch impedance and an electronic device. The power supply circuit includes N main channel MOS transistors, a control module, an execution module and a detection module, wherein the execution module includes a first MOS transistor; the detection module includes a detection resistor and a second MOS transistor; a gate-source voltage of the main channel MOS transistors and a gate-source voltage of the first MOS transistor are configured to be consistent, and a source-drain voltage of the main channel MOS transistors and a source-drain voltage of the second MOS transistor are consistent; the control module is connected to the detection resistor and configured to: detect voltage drop information on voltage drop at two ends of the detection resistor, wherein the voltage drop information can represent a current of a load.

A switch control circuit and a switch control method are provided. The switch control circuit includes a load, an inductor, a control switch, and a sensing resistance connected in series to an input power; an integrator that integrates a sensing voltage and a load current setting voltage to generate an integrated signal; a comparator that compares the integrated signal and a bias voltage; a switch driver that controls the control switch based on an output of the comparator and an output of an off time controller; and a gate sensor that outputs, to the integrator, a gate sensing signal that senses a time when an input of a gate terminal of the control switch becomes a low level. An integration operation is started from a position in which the integrated signal is located lower than the bias voltage, when an input of the gate terminal becomes a high level.

In order both to accommodate instantaneous current as well as overcurrent protection in accordance with the load, an overcurrent protection circuit has: a threshold value generation unit that, in accordance with a threshold value control signal, switches between setting an overcurrent detection threshold value to a first set value (∝ Iref) and a second set value (∝ Iset) lower than the first set value; an overcurrent detection unit that compares a sense signal in accordance with the current being monitored and the overcurrent detection value and generates an overcurrent protection signal; a reference value generation unit that generates a reference value (∝ Iset) in accordance with the seconds set value; a comparison unit that compares the sense signal and the reference value, and generates a comparison signal; and a threshold value control unit that monitors the comparison signal, and generates a threshold value control signal.

A circuit arrangement is disclosed for controlling the switching of a field effect transistor (FET). A current controlled amplifier may be configured to amplify a current in a current sense device to generate an amplified current, wherein the current in the current sense device indicates a current through the FET. A comparator may be coupled to the current sense amplifier to compare a voltage corresponding to the amplified current with a voltage reference and to generate a comparator output based on the comparison, wherein the comparator output controls whether the FET is on or off.

A switch-mode power supply circuit includes a low-side switching transistor, a high-side switching transistor, a low-side current sensing circuit, and a gate driver circuit. The low-side current sensing circuit is coupled to the low-side switching transistor and is configured to sense a current flowing through the low-side switching transistor. The gate driver circuit is coupled to the low-side current sensing circuit and the high-side switching transistor. The gate driver circuit is configured to generate a signal having a first drive strength to switch the high-side switching transistor based on current flowing through the low-side switching transistor being less than a threshold current, and to generate a signal having a second drive strength to switch the high-side switching transistor based on current flowing through the low-side switching transistor being greater than the threshold current. The first drive strength is greater than the second drive strength.

An electrical switching system includes a constant-power controller and a switching device electrically coupled between a first node and a second node. The constant-power controller is configured to (a) generate a digital control signal to control the switching device, (b) control a duration of an active phase of the digital control signal at least partially based on a voltage across the switching device, and (c) control a peak value of the digital control signal to regulate a peak magnitude of current flowing through the switching device.

Systems, methods, techniques and apparatuses of a semiconductor control system are disclosed. One exemplary embodiment is a method for protecting a semiconductor switch comprising receiving a first voltage during a second blanking period following a first blanking period; determining whether a short circuit fault is occurring by comparing the first voltage to a fast detection threshold corresponding to a first value of a drain-source voltage of the semiconductor switch; if a short circuit is not occurring: receiving a second voltage after the second blanking period ends; determining whether a short circuit fault is occurring by comparing the second voltage to a slow detection threshold corresponding to a second value of the drain-source voltage; and if a short circuit fault is occurring, opening the semiconductor switch, wherein the first value of the drain-source voltage is greater than the second value of the drain-source voltage.

An overcurrent protection circuit configured to limit an output current flowing through an output transistor includes a sense transistor that provides a sense current proportional to the output current, a sense resistor through which the sense current flows, a current limiting circuit that detects a sense voltage generated by the sense resistor and controls a gate voltage of the output transistor, and a current correction circuit that provides the sense resistor with a corrected sense current added to the sense current based on a difference of voltage between a drain voltage of the output transistor and a drain voltage of the sense transistor.

An integrated circuit, including: a first current source; a second current source provided in parallel to the first current source; a first resistor with one end coupled to an output of the first current source; a first bipolar transistor that is diode-connected and is coupled to the other end of the first resistor; a second bipolar transistor that is diode-connected and is coupled to an output of the second current source; a second resistor coupled to the second bipolar transistor; and an output circuit configured to output a voltage based on a first voltage outputted from the first current source and a second voltage outputted from the second current source.

A power circuit with a first transistor, including a first terminal connected to a first node, a second terminal connected to an input node, and a control terminal connected to a first control node, and a second transistor, including a first terminal connected to the first node, a second terminal connected to an output node, and a control terminal connected to a second control node. A third transistor includes a first terminal connected to the first control node, a second terminal connected to a second node, and a control terminal, and a fourth transistor includes a first terminal connected to the output node, a second terminal connected to the second control node, and a control terminal connected to a third node. The power circuit also includes a current limiting circuit coupled between the second node and the third node.