Converter circuit for current mode control

Claim 1

A converter circuit operable in a current control mode for controlling the current provided to a load, said circuit comprising: inductance means, coupled to said load, for conducting a steady state waveform of inductor current having an increasing portion with a positive slope, a decreasing portion with a negative slope and an average value; clocking means for generating a clocking signal at a predetermined frequency; means for generating a threshold current at a predetermined slope and level; means for generating a switching signal during each cycle of said clocking signal when the inductor current equals a threshold current level; switching means, responsive to said clocking signal and said threshold current, for controlling the voltage at one end of said inductance means between two different levels of voltages respectively as a function of two supply voltages so that said inductance means conducts (1) increasing inductor current for one level of load voltage from the beginning of each cycle of said clocking signal until the inductor current equals said threshold current during each cycle, and (2) decreasing inductor current for the other level of voltage from the time in each cycle the current equals said threshold current until the end of each said cycle; and wherein said means for generating said threshold current generates said threshold current as a function of said load and supply voltages so that said predetermined slope and level of the threshold current is a desired steady state solution of said decreasing inductor current so that any perturbations of said inductor current immediately converges to the steady state waveform at the time in each cycle the current equals the threshold current.