DC-to-DC converter controllers including over-current protection, and associated systems and methods

摘要

A DC-to-DC converter includes a switching circuit, an energy storage inductor electrically coupled to the switching circuit, and a controller. The controller includes a control signal generator, a current sensing subsystem, an over-current detection subsystem, and filter logic. The control signal generator generates unfiltered control signals to control the switching circuit, and the current sensing subsystem senses current flowing through the energy storage inductor. The over-current detection subsystem asserts an over-current signal if a magnitude of positive current flowing through the energy storage inductor exceeds a maximum permissible value. The filter logic filters the unfiltered control signals to generate filtered control signals in response to assertion of the over-current signal, such that respective widths of one or more pulses of the filtered control signals are less than respective widths of corresponding pulses of the unfiltered control signals.

主权项

1. A DC-to-DC converter, comprising:
a switching circuit; an energy storage inductor electrically coupled to the switching circuit; and a controller, including:
a control signal generator adapted to generate unfiltered control signals to control the switching circuit, the control signal generator including:
error circuitry adapted to set a voltage at an error node as a function of a difference between an actual output voltage of the DC-to-DC converter and a desired output voltage of the DC-to-DC converter,an impedance network electrically coupled between the error node and an integration node,an integration subsystem adapted to integrate current flowing through the impedance network to generate a modulator control signal, anda modulator adapted to generate the unfiltered control signals from at least the modulator control signal,the impedance network being electrically coupled in series with the error circuitry and the integration subsystem,a current sensing subsystem adapted to sense current flowing through the energy storage inductor,an over-current detection subsystem adapted to assert a first over-current signal if a magnitude of positive current flowing through the energy storage inductor exceeds a first maximum permissible value, andfilter logic adapted to filter the unfiltered control signals to generate filtered control signals in response to assertion of the first over-current signal, such that respective widths of one or more pulses of the filtered control signals are less than respective widths of corresponding pulses of the unfiltered control signals.