US 2019/0103816 A1 · POWER CONVERSION DEVICE AND VOLTAGE REGULATING FEEDBACK CIRCUIT

Abstract

A power conversion device includes a transformer having a primary winding and a secondary winding, a switch coupled between the primary winding and a primary ground, a control circuit configured to output a control signal to turn on or off the switch selectively, a secondary circuit coupled to the secondary winding and configured to output an output voltage, a voltage regulating feedback circuit coupled to the secondary circuit, and an isolation circuit coupled between the voltage regulating feedback circuit and the control circuit. On the condition that the output voltage is greater than an upper limit, the voltage regulating feedback circuit is configured to output a feedback signal via the isolation circuit to the control circuit such that the control circuit turns off the switch.

Claims15

Dependent claims

A power conversion device comprising:

a transformer comprising a primary winding and a secondary winding;
a switch electrically coupled between the primary winding and a primary ground;
a control circuit configured to output a pulse width modulation control signal to turn on or off the switch selectively;
a secondary circuit electrically coupled to the secondary winding and configured to output an output voltage;
a voltage regulating feedback circuit electrically coupled to the secondary circuit;
and
an isolation circuit electrically coupled between the voltage regulating feedback circuit and the control circuit;
wherein on the condition that the output voltage is greater than an upper limit, the voltage regulating feedback circuit is configured to output a feedback signal via the isolation circuit to the control circuit such that the control circuit slops outputting the pulse width modulation control signal and turns off the switch.

5 more elements

A voltage regulating feedback circuit comprising:

a first diode unit, wherein an anode of the first diode unit is configured to receive an output voltage outputted by an output terminal of a power conversion device;
a Zener diode unit, wherein a cathode of the Zener diode unit is electrically coupled to a cathode of the first diode unit;
and
a first voltage dividing unit electrically coupled to an anode of the Zener diode unit and an isolation circuit;
wherein on the condition that the output voltage of the power conversion device is greater than an upper limit, the Zener diode unit reversely breakdowns such that a first current flows through a secondary side of the isolation circuit and a primary side of the isolation circuit conducts accordingly to provide a feedback signal to a primary side of the power conversion device in order that the power conversion device stops outputting a pulse width modulation control signal and turn off a switch of the power conversion device to as to reduce the output voltage.

2 more elements

Dependencies are inferred from the claim text.

Power conversion device and voltage regulating feedback circuit

Life of this patent

Power conversion device and voltage regulating feedback circuit

Life of this patent

Abstract

Claims15