SWITCHED POWER CONVERTER WITH DUAL MODE PWM / COT CONTROL

摘要

The present invention relates to a power converter. The power converter includes: a switch-type power stage configured to generate an output voltage from an input voltage; and a controller configured to generate a pulsed control signal for switching the switch-type power stage depending on a voltage error signal. The voltage error signal is a difference between a reference voltage and the output voltage. The controller includes a digital pulse width modulation (PWM) control path and a digital constant on-time control path. The controller is configured to toggle between a light load mode in which a digital constant on-time is activated and a high load mode in which the digital PWM control path is activated. The present invention designs a digital constant one-time control path compared to a conventional constant one-time control path configured as a separate analog circuit including a continuous time comparator which is configured to compare a voltage error with a threshold value for triggering a preset constant on-time pulse and consumes an additional space and additional power.