| 摘要 |
A generic voltage converter outputs at least two voltages: a Vo potential that is regulated using output-to-input feedback to a PWM that controls duty cycle of the converter switch, and a VoAUX potential available from a post-linear regulator. Output-to-input feedback is provided from the post-linear regulator to a node in the PWM, e.g., COMP, SoftStart, VFB. Whenever the post-linear regulator senses excessive VoAUX current, feedback from the regulator commands the PWM to reduce converter duty cycle, which reduces VinAUX, as well as VoAUX and Vo, without cross-regulation. The topology minimizes thermal dissipation within the regulator pass element by saturating the pass element at maximum VoAUX current flow such that at maximum current flow there is minimal voltage drop across the pass element.
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