Enhanced peak current mode DC-DC power converter

摘要

Apparatus and methods are provided for feedback circuitry in a power converter, the feedback circuitry including a first resistor coupled to a first node between a high switch and a low switch, a first capacitor in series with the first resistor, the first capacitor coupled to a second node, a first comparator having a positive terminal connected between the first resistor and the first capacitor and a negative terminal connected to a third node, the first comparator configured to compare a voltage at the positive terminal to a voltage at the negative terminal, wherein the feedback circuitry is configured to generate a ramp waveform at the positive terminal of the first comparator, an amplitude of the ramp waveform based on a time constant of the first resistor and the first capacitor.

主权项

1. Feedback circuitry for a power converter, the feedback circuitry comprising:
a first resistor coupled to a first node between a high switch and a low switch; a first capacitor in series with the first resistor, the first capacitor coupled to a second node; a first comparator having a positive terminal connected between the first resistor and the first capacitor and a negative terminal connected to a third node, the first comparator configured to compare a voltage at the positive terminal to a voltage at the negative terminal, wherein the feedback circuitry is configured to generate a ramp waveform having an amplitude based on a time constant of the first resistor and the first capacitor and provide the ramp waveform to the positive terminal of the first comparator; and a second capacitor in parallel with the first capacitor; and a switch in series with the second capacitor, the switch configured to close once per clock cycle.