Dead-time compensation in a power supply system

摘要

A power supply system (10) includes a pulse-width modulation (PWM) system (14) configured to generate a PWM signal. The system (10) also includes a power stage (16) comprising a gate driver (60), a high-side switch, and a low-side switch. The gate driver (60) can be configured to alternately activate the high-side and low-side switches to provide an output signal to a load (12) in response to the PWM signal, and to provide an activation dead-time between the alternate activation of the high-side and low-side switches. The system (10) further includes a digital delay system (18) configured to measure the activation dead-time and to add the measured activation dead-time to the activation of the high-side switch.

主权项

1. A power supply system comprising:
a pulse-width modulation (PWM) system configured to generate a PWM signal; a power stage comprising a gate driver, a high-side switch, and a low-side switch, the gate driver being configured to alternately activate the high-side and low-side switches to provide an output signal to a load in response to the PWM signal, and to provide an activation dead-time between the alternate activation of the high-side and low-side switches; and a digital delay system configured to measure the activation dead-time and to add the measured activation dead-time to the activation of the high-side switch, the digital delay system comprising a PWM adjust circuit including:
a NOR gate configured to generate a reset signal in response to the PWM signal and a delay signal associated with the measured activation dead-time; andan SR-latch configured to generate a control signal in response to the PWM signal being provided to an S input and the reset signal being provided to the R input, the control signal having a pulse-width that is greater than the PWM signal by an amount that is approximately equal to the measured activation dead-time, the control signal being provided to the gate driver for alternately activating the high-side and low-side switches.