System and method for current limiting a DC-DC converter

摘要

A DC-DC voltage converter has a pair of switching transistors to provide an output voltage and are alternately switched in a boost mode of operation responsive to control signals. An inductor is connected to the pair of switching transistor and has an inductor current flowing there through. A current sensor monitors an input current and generates a current sense signal responsive thereto. Control circuitry generates the control signals to the second pair of switching transistors responsive to the current sense signal, the output voltage and a current limit signal, wherein when the current limit signal indicates the inductor current exceeds a current limit the control signals configure the pair of switching transistors to decrease the inductor current.

主权项

1. A DC-DC voltage converter, comprising:
a pair of switching transistors providing an output voltage that are alternately switched in a boost mode of operation responsive to control signals; an inductor connected with the pair of switching transistors having an inductor current flowing therethrough, the inductor current having alternating peak current values and valley current values; a current sensor connected to monitor an input current generating a current sense signal; and control circuitry for generating the control signals to the pair of switching transistors responsive to the current sense signal, the output voltage and a current limit signal, the control circuitry having a valley current control mode of operation and a current limit function that is responsive to the valley current values of the inductor current.