Patent ID: 9634564
Date: 2017-04-25
CPC Classifications: H02M

Claim:
1. A control circuit of a digital control power supply circuit, comprising: an A/D converter that samples a feedback voltage according to an output voltage of the digital control power supply circuit when a strobe signal is asserted and that converts the sampled feedback voltage into digital feedback data; an error detector that generates error data which indicates a difference between the feedback data received from the A/D converter and target data indicating a target value of the feedback voltage; a compensator that generates a duty command value which is adjusted to approximate the error data received from the error detector to zero; a digital pulse width modulator that receives the duty command value from the compensator and that generates a pulse signal having a duty ratio corresponding to the received duty command value; and a strobe signal generator that generates the strobe signal, and that adjusts a sampling timing at which the strobe signal is asserted such that the sampling timing approximates a target position set in a substantial center of a slope of the output voltage, wherein the strobe signal generator comprises: a period counter that asserts the strobe signal at every period which depends on a variable period set value; and a period setting unit that sets the target position, that obtains an error time between the sampling timing and the target position, and that sets the period set value based on the error time.