US 6,473,316 B2 · Phase control circuit and switching regulator

Abstract

A phase control circuit which can stabilize voltage control when used in a switching regulator, and a switching regulator using such a phase control circuit are provided. A switching circuit for generating a first and a second output signals having opposite polarities based on a clock signal, is provided. A PWM latch circuit, reset by a reset signal, for generating a third and a fourth output signals which have phases controlled with respect to the first and the second output signals respectively by a set signal produced based on a control signal and come to have opposite polarities, is provided. A delay circuit for delaying the rising of each of the first through the fourth output signals before outputting each of the first through the fourth output signals is provided for each output signal. A delay clock pulse width setting circuit for generating a delay pulse based on low level periods of the delayed first and second output signals is provided so as to reset the PWM latch circuit using the delay pulse as the reset signal.

Claims20

Dependent claims

A phase control circuit comprising:

a first pair of output stages for generating a first output signal and a second output signal based on a clock signal so that said first and said second output signals are pulse signals having opposite polarities;
a second pair of output stages, reset by a reset signal, for generating a third output signal and a fourth output signal which have phases controlled with respect to the first and the second output signals by the first and the second output signals respectively and also by a set signal produced based on a control signal, so that said third and said fourth output signals are pulse signals having opposite polarities;
first delay means for delaying, before output, the rising of the first through the fourth output signals;
and
delay pulse means for generating a delay pulse based on low level periods of the delayed first and second output signals, and for resetting said second pair of output stages using said delay pulse as said reset signal.

2 more elements

A switching regulator comprising:

a first half bridge circuit including a first switch and a second switch, connected in series, which are turned on/off according to a high/low signal;
a second half bridge circuit including a third switch and a fourth switch, connected in series, which are turned on/off according to a high/low signal;
a transformer whose primary is connected to said first and second half bridge circuits;
a resonant circuit, connected between said first and second half bridge circuits in series with the primary of said transformer, for soft switching so as to decrease switching loss;
a rectifier circuit connected to a secondary of said transformer;
a control signal generator circuit for generating a control signal to feed back and control an output from said rectifier circuit, based on said output;
and
a phase control circuit for controlling the turning on/off of the first through the fourth switches,
said phase control circuit comprising:
a first pair of output stages for generating a first output signal and a second output signal based on a clock signal so that said first and said second output signals are pulse signals having opposite polarities;
a second pair of output stages, reset by a reset signal, for generating a third output signal and a fourth output signal which have phases controlled with respect to the first and the second output signals by the first and the second output signals respectively and also by a set signal produced based on a control signal, so that said third and said fourth output signals are pulse signals having opposite polarities;
first delay means for delaying, before output, the rising of the first through the fourth output signals;
and
delay pulse means for generating a delay pulse based on low level periods of the delayed first and second output signals, and for resetting said second pair of output stages using said delay pulse as said reset signal, and
the first through the fourth switches of said switching regulator being respectively connected to the first through the fourth output signals of said phase control circuit.

12 more elements

Dependencies are inferred from the claim text.

Phase control circuit and switching regulator

Life of this patent

Phase control circuit and switching regulator

Life of this patent

Abstract

Claims20