SWITCHING MODE POWER SUPPLY WITH ADAPTIVELY RANDOMIZED SPREAD SPECTRUM

摘要

In described examples, a switching mode power supply includes an output filter, a driver, a pulse width modulator, and pulse adaptation circuitry. The output filter is configured to provide output of the switching mode power supply. The driver is coupled to the output filter and is configured to switch current to the output filter. The pulse width modulator is configured to generate pulses that control switching of current by the driver. The pulse width modulator includes spread spectrum logic configured to randomize timing of the pulses generated by the pulse width modulator. The pulse adaptation circuitry is configured to identify an instantaneous excursion of the output of the switching mode power supply beyond a predetermined threshold, and to modify the randomized timing of the pulses produced by the pulse width modulator based on the identified instantaneous excursion.

主权项

1. A switching mode power supply, comprising:
an output filter configured to provide output of the switching mode power supply; a driver coupled to the output filter and configured to switch current to the output filter; a pulse width modulator configured to generate pulses that control switching of current by the driver, the pulse width modulator including: spread spectrum logic configured to randomize timing of the pulses generated by the pulse width modulator; and pulse adaptation circuitry; wherein the pulse adaptation circuitry is configured to: identify an instantaneous excursion of the output of the switching mode power supply beyond a predetermined threshold; and modify the randomized timing of the pulses produced by the pulse width modulator based on the identified instantaneous excursion.