Self-adaptive soft turn-on of power switching devices
AssigneeSTMicroelectronics S.r.l.
InventorsCostanzo Lorenzo, Patti Davide Giuseppe, Tagliavia Donato
Life of this patent
Estimating the term…
Abstract
An embodiment of a control circuit is proposed for turning on a power switching device, the switching device turning on in response to a control signal exceeding a threshold value. The control circuit includes pre-charging means for providing the control signal at a pre-charging value not reaching the threshold value, and soft turn-on means for gradually increasing the control signal from the pre-charging value to a turn-on value exceeding the threshold value; the pre-charging means includes means for sensing an indication of the threshold value, and means for setting the pre-charging value according to the sensed threshold value.
Claims36
A control circuit for turning on a power switching device, the switching device turning on in response to a control signal exceeding a threshold value, wherein the control circuit includes:
- pre-charging means for providing the control signal at a pre-charging value not reaching the threshold value, and
- soft turn-on means for gradually increasing the control signal from the pre-charging value to a turn-on value exceeding the threshold value,
- wherein the pre-charging means includes:
- means for sensing an indication of the threshold value, and
- means for setting the pre-charging value according to the sensed threshold value.
A method for turning on a power switching device, the switching device turning on in response to a control signal exceeding a threshold value, wherein the method includes the steps of:
- pre-charging the switching device by providing the control signal at a pre-charging value not reaching the threshold voltage, and
- soft turning-on the switching device by gradually increasing the control signal from the pre-charging value to a turn-on value exceeding the threshold value,
- wherein the step of pre-charging includes:
- sensing an indication of the threshold value, and
- setting the pre-charging value according to the sensed threshold value.
A bias generator for biasing a device, the bias generator comprising:
- a first circuit operable to determine a turn-on threshold of the device;
- and
- a second circuit operable to provide to the device a bias signal having a magnitude that is related to the turn-on threshold.
A bias generator for biasing a device, the bias generator comprising:
- a first circuit operable to determine a turn-on threshold of the device;
- and
- a second circuit operable to provide to the device a bias signal having a magnitude that is related to the turn-on threshold, wherein:
- the first circuit comprises a MOS transistor having substantially the turn-on threshold;
- and
- the second circuit comprises an amplifier operable to receive from the first circuit a signal that represents the turn-on threshold of the MOS transistor and to generate the bias signal by amplifying the first circuit signal with a gain that is less than unity.
A drive circuit, comprising:
- a drive device having a control node and a first activation threshold;
- a first circuit operable determine the first activation threshold;
- and
- a second circuit operable
- to receive an indication of the first activation threshold from the first circuit, and
- to provide to the control node of the drive device a bias signal having a magnitude that is related to the first activation threshold.
A drive circuit, comprising:
- a drive device having a control node and a first activation threshold;
- a first circuit operable determine the first activation threshold;
- and
- a second circuit operable to receive an indication of the first activation threshold from the first circuit, and
- to provide to the control node of the drive device a bias signal having a magnitude that is related to the first activation threshold, further comprising:
- first and second current sources;
- and
- a logic circuit operable
- to receive an activation signal,
- to couple the first current source to the control node of the first device for a first time in response to receiving the activation signal, and
- to couple the second current source to the control node of the first device after the first time expires.
A system, comprising:
- a first integrated circuit comprising
- a drive device having a control node and a first activation threshold,
- a first circuit operable determine the first activation threshold, and
- a second circuit operable
- to receive an indication of the first activation threshold from the first circuit, and
- to provide to the control node of the drive device a bias signal having a magnitude that is related to the first activation threshold;
- and
- a second integrated circuit coupled to the first integrated circuit.
A method, comprising:
- generating a bias signal that tracks a turn-on threshold of a device;
- biasing the device with the bias signal.
A method comprising:
- generating a bias signal that tracks a turn-on threshold of a device;
- biasing the device with the bias signal, further comprising:
- wherein generating the bias signal comprises generating a bias voltage;
- wherein biasing the device comprises charging an input capacitance of the device to the bias voltage;
- turning on the biased device by further charging the input capacitance with a substantially constant current.
Dependencies are inferred from the claim text.