×

Output current control circuit for power converter with a changeable switching frequency

  • US 7,778,051 B2
  • Filed: 03/14/2007
  • Issued: 08/17/2010
  • Est. Priority Date: 03/14/2007
  • Status: Active Grant
First Claim
Patent Images

1. An output current control circuit for a power converter, comprising:

  • a current-detection circuit, coupled to a current sense device, for generating a primary-current signal in response to a primary-side switching current of a transformer;

    a voltage-detection circuit, coupled to the transformer, for generating a period signal and a discharge-time signal in response to a reflected voltage of the transformer;

    a signal-process circuits, for generating a current signal in response to the primary-current signal, the period signal and the discharge-time signal;

    a switching control circuit, coupled to the signal-process circuit, for generating a switching signal in response to the current signal; and

    a pulse generator, coupled to the voltage-detection circuit, for generating a sample-pulse signal in response to the period signal,wherein the switching signal is utilized to switch the transformer and regulate the output current of the power converter;

    the period signal is correlated to the switching period of the switching signal, the discharge-time signal is correlated to the duty cycle of a secondary-side switching current of the transformer;

    the current signal is correlated to the output current of the power converter;

    the sample-pulse signal is used to control sampling of the signal-process circuit.

View all claims
  • 5 Assignments
Timeline View
Assignment View
    ×
    ×