Disclosed are a doorbell system and a method for controlling a doorbell system that includes a shunt unit electrically connected to a signaling unit of a doorbell system, a power harvest unit electrically connected to the shunt unit and the signaling unit, a first switch unit, the power harvest unit being selectively connected to an external power source via the first switch unit, a button unit that receives a press operation, and a detection and control unit that detects whether there is a press operation, and controls the first switch unit to be in a first mode when no press operation is detected, the power harvest unit harvests power from the external power source via the first switch unit in the first mode, and controls the first switch unit to be in a second mode and controls the signaling unit to make sound when the press operation is detected.

Disclosed are a doorbell system and a method for controlling a doorbell system that includes a shunt unit electrically connected to a signaling unit of a doorbell system, a power harvest unit electrically connected to the shunt unit and the signaling unit, a first switch unit, the power harvest unit being selectively connected to an external power source via the first switch unit, a button unit that receives a press operation, and a detection and control unit that detects whether there is a press operation, and controls the first switch unit to be in a first mode when no press operation is detected, the power harvest unit harvests power from the external power source via the first switch unit in the first mode, and controls the first switch unit to be in a second mode and controls the signaling unit to make sound when the press operation is detected.

A resonant power converter controller comprising a control circuit configured to turn on a synchronous rectifier (SR) in response to a count of a number of times a drain voltage of the SR crosses below a turn on threshold based on a stored count and turns off the SR when the drain voltage crosses above a turn off threshold. The control circuit comprises a first comparator configured to generate a first detection signal in response to the drain voltage being less than the turn on threshold. A first turn on detection circuit generates a first turn on signal when the count reaches the stored count. A first turn off signal is generated in response to the drain voltage being greater than the turn off threshold. A drive circuit turns on and off the SR in response to the first turn on signal and the first turn off signal.

A switch system includes a bidirectional switch, a first gate driver circuit, a second gate driver circuit, a control unit, a first decision unit, and a second decision unit. The bidirectional switch includes a first source, a second source, a first gate, and a second gate. The first decision unit determines, based on a voltage at the first gate and a first threshold voltage, a state of the first gate in a first period in which a signal to turn OFF the first gate is output from the control unit to the first gate driver circuit. The second decision unit determines, based on a voltage at the second gate and a second threshold voltage, a state of the second gate in a second period in which a signal to turn OFF the second gate is output from the control unit to the second gate driver circuit.

The invention relates to a method, a device and a system for monitoring the IGBT junction temperature, wherein the linear relationship between each turn-off DC bus ringing peak voltage and the corresponding turn-off IGBT junction temperature, the phase current directions, and the initial and secondary states of the half-bridge arms are used to accurately determine the monitoring time of the turn-off DC bus ringing peak voltage, thereby obtaining the IGBT junction temperature at a converter level with higher sensitivity. The IGBT junction temperature obtained using the junction temperature monitoring method provided by the invention is an appropriate converter-level parameter, which has a good application prospect in multi-IGBT junction temperature estimation.

An electronic circuit is disclosed. The electronic circuit includes: a half-bridge with a first transistor device (1) and a second transistor device (1a); a first biasing circuit (3) connected in parallel with a load path of the first transistor device (1) and comprising a first electronic switch (31); a second biasing circuit (3a) connected in parallel with a load path of the second transistor device (1a) and comprising a second electronic switch (31a); and a drive circuit arrangement (DRVC). The drive circuit arrangement (DRVC) is configured to receive a first half-bridge input signal (Sin) and a second half-bridge input signal (Sina), drive the first transistor device (1) and the second electronic switch (31a) based on the first half-bridge input signal (Sin), and drive the second transistor device (1a) and the first electronic switch (31) based on the second half-bridge input signal (Sina).

An electronic circuit is disclosed. The electronic circuit includes: a half-bridge with a first transistor device (1) and a second transistor device (1a); a first biasing circuit (3) connected in parallel with a load path of the first transistor device (1) and comprising a first electronic switch (31); a second biasing circuit (3a) connected in parallel with a load path of the second transistor device (1a) and comprising a second electronic switch (31a); and a drive circuit arrangement (DRVC). The drive circuit arrangement (DRVC) is configured to receive a first half-bridge input signal (Sin) and a second half-bridge input signal (Sina), drive the first transistor device (1) and the second electronic switch (31a) based on the first half-bridge input signal (Sin), and drive the second transistor device (1a) and the first electronic switch (31) based on the second half-bridge input signal (Sina).

A circuit comprises a gate driver having a supply voltage terminal and configured to generate an output at an output terminal based on an input. A voltage multiplexer is configured to connect a first voltage terminal to the supply voltage terminal responsive to a voltage select signal having a first value and connect a second voltage terminal to the supply voltage terminal responsive to the voltage select signal having a second value. First logic is configured to generate a fault signal responsive to detecting one of a first fault condition associated with operation of the gate driver or a second fault condition associated with operation of the gate driver and generate the voltage select signal having the second value based on the fault signal. Second logic is configured to generate the voltage select signal having the second value after a predetermined delay period based on a value of the input.

A large-current MOS drive control method, comprising the following steps: 1) turning on a device, initializing the device, activating an MOS switching circuit, and completing a turn-on operation for the circuit; 2) monitoring the voltage connected to the switching circuit, connecting the switching circuit to a power supply after voltage detection, and activating the power supply; 3) connecting the power supply to a control circuit, processing, by the control circuit, information transmitted by the power supply, and driving, by the control circuit, a driving circuit; and 4) after the MOS switching circuit is connected, measuring the temperature of the switching circuit in real time by means of an infrared temperature measurement instrument, and if the temperature exceeds 80 Celsius degrees, giving an alarm by flashing a red alarm lamp.

A large-current MOS drive control method, comprising the following steps: 1) turning on a device, initializing the device, activating an MOS switching circuit, and completing a turn-on operation for the circuit; 2) monitoring the voltage connected to the switching circuit, connecting the switching circuit to a power supply after voltage detection, and activating the power supply; 3) connecting the power supply to a control circuit, processing, by the control circuit, information transmitted by the power supply, and driving, by the control circuit, a driving circuit; and 4) after the MOS switching circuit is connected, measuring the temperature of the switching circuit in real time by means of an infrared temperature measurement instrument, and if the temperature exceeds 80 Celsius degrees, giving an alarm by flashing a red alarm lamp.