Interference suppression for switched mode power supply with error correction

摘要

A switched mode power supply arranged to provide a switched supply at one terminal of an inductor, another terminal of the inductor being connected to a first input of an error amplifier having a reference signal at a second input, the error amplifier generating a corrected switched supply at an output in dependence on the difference between signals at its first and second inputs, there being provided a feedback path between the output of the error amplifier and the first input of the error amplifier, and further comprising circuitry for sensing a switcher interference current in the feedback path of the error amplifier, and for adjusting the corrected switched supply output to reduce the switcher interference current in the output.

主权项

1. A switched mode power supply comprising:
a first inductor arranged to receive a switched supply at one terminal; an error amplifier having a first input connected to an other terminal of the first inductor and a second input connected to a reference signal, the error amplifier being configured to generate a corrected switched supply at an output of the error amplifier in dependence on a difference between signals at the first and second inputs; an impedance connected between the output of the error amplifier and the other terminal of the first inductor; a resistor connected between the other terminal of the first inductor and the first input of the error amplifier; and a second inductor connected between the first input of the error amplifier and the output of the error amplifier.