A bus interface bus is described. A first logical state is conveyed over the bus by a higher voltage level and a second logical state is conveyed by a lower voltage level. An output stage of the interface includes a power transistor configured to drive the lower voltage level onto the bus to convey the second logical state, and a protective device between the power transistor and the bus. The protective device couples the power transistor to the bus when turned on and limits negative voltage excursions at the power transistor when turned off. A control circuit of the interface is configured to turn on the protective device when the bus voltage is above the lower voltage level and to turn off the protective device when the bus voltage is at or below the lower voltage level.

A linear power supply circuit includes: an output stage including a first output transistor and a second output transistor, which are provided between an input terminal to which an input voltage is able to be applied and an output terminal to which an output voltage is able to be applied and are connected in parallel to each other; a driver configured to drive the first output transistor and the second output transistor based on a difference between a voltage based on the output voltage and a reference voltage; a resistor inserted between a gate of the first output transistor and a gate of the second output transistor; a capacitor having one end connected to the input terminal and the other end connected to a connection node between the resistor and the gate of the second output transistor; and a clamp element connected in parallel to the resistor.

In a switching circuit apparatus, first and second capacitors apply power supply voltages to first and second drive circuits. First and second diodes are connected such that currents flow from a DC voltage source to the first and second capacitors. A resistor and a Zener diode are connected in series between a terminal and a node, such that a reverse bias voltage is applied from the terminal to the Zener diode via the resistor. A third diode is connected such that a current flows to the first capacitor from a node (N2) between the resistor and the Zener diode.

A method is described. The method comprises determining a first measurement signal (CS1) which depends on a first load current (I1) through a first transistor (Q1) which is connected in series to a load (Z); determining a second measurement signal (CS2) which depends on a second load current (I2) through a second transistor (Q2) which is connected in series to the load (Z); and comparing the first measurement signal (CS1) and the second measurement signal (CS2), in order to detect the presence of an error.

A signal switching apparatus includes a signal control switch, a switch circuit, a blocking capacitor and a surge current dissipating circuit. The signal control switch coupled between a first signal transceiving end and a second signal transceiving end is turned on or turned off according to a first control signal. The switch circuit having at least one first transistor is controlled by a second control signal to be turned on or off, and a first end of the switch circuit is coupled to the first signal transceiving end. The blocking capacitor is coupled between a second end of the switch circuit and a reference voltage terminal. The surge current dissipating circuit having at least one second transistor is coupled between the second end of the switch circuit and the reference voltage terminal. The second transistor is configured to dissipate a surge current and also turned off when operated normally.

A switching circuit has a primary MOSFET switch connected between first and second terminals that are connected to a power line and a load represented as a resistance and inductance. The primary switch is operable by primary control commands to assume a conductive or non-conductive state. Four protection branches are connected in parallel with the primary switch, each having a series connected resistive element and a secondary MOSFET switch operable by branch control commands received at branch command terminals to assume a conductive or non-conductive state. A timing circuit applies branch turn off control commands in sequence to the branch command terminals, each delayed by a different predetermined time interval relative to when a primary turn off control command is applied to the primary switch.

A semiconductor device includes a semiconductor body having an active region and a substrate region that is disposed beneath the active region, and a bidirectional switch formed in the semiconductor body. The bidirectional switch includes first and second gate structures that are each configured to control a conductive state of an electrically conductive channel that is disposed in the active region, and first and second input-output terminals that are each in ohmic contact with the electrically conductive channel. A passive substrate voltage discharge circuit in parallel with the bidirectional switch is configured to discharge a voltage of the substrate region in both directions of the bidirectional switch. The passive substrate voltage discharge circuit includes first and second normally-on switches connected in anti-series between the first and second input-output terminals in a common source configuration with the substrate region as a midpoint.

The present disclosure provides a hot-swap circuit and a control apparatus. The hot-swap circuit includes: a power input terminal, a power output terminal; a startup module electrically connected to the power input terminal and the power output terminal; a switch module electrically connected to the power input terminal, the power output terminal, and the startup module; a detection module electrically connected to the startup module, the switch module, and the power output terminal. When a surge signal is input at the power input terminal, a voltage value of a first control signal output by the detection module doesn't fall in a voltage value range of a preset first control signal, then the switch module is controlled to be turned off, so as to cut off a power signal input to the power output terminal, reducing probability of circuit damage, and reducing sparking phenomena of hot-swap power interfaces.

A circuit for detecting failure of a device includes an on-phase detector, an off-phase detector, and protection switch circuitry. The on-phase detector is configured to determine whether a first failure has occurred at the device based on a rate of change of a current at a high-side switching element. The off-phase detector is configured to determine whether a second failure has occurred at the device based on both a current at a low-side switching element and a voltage at a switch node that is electrically coupled to the high-side switching element and the low-side switch. The protection switch circuitry is configured to electrically disconnect the high-side switching element from a supply circuit in response to the on-phase detector determining that the first failure has occurred at the device or in response to the off-phase detector determining that the second failure has occurred at the device.

A protected direct-drive depletion-mode (D-mode) GaN semiconductor half-bridge power module is disclosed. Applications include high power inverter applications, such as 100kW to 200kW electric vehicle traction inverters, and other motor drives. The high-side switch is a normally-on D-mode GaN semiconductor power switch Q1 in series with a normally-off LV Si MOSFET power switch M1 and the low-side switch is a normally on D-mode GaN semiconductor power switch Q2. The gates of both Q1 and Q2 are directly driven. M1 in series with Q1 provides a high-side switch which is a normally-off device for start-up and fail-safe protection. M1 may also be used for current sensing and overcurrent protection. For example, a control circuit determines an operational mode of M1 responsive to a UVLO signal and a voltage sense signal indicative of an overcurrent event. Examples of single phase and three-phase half-bridge modules and driver circuits are described.