Patent ID: 6700365
Filing Date: 2004-03-02
Classification: G01R,G05F,H02M

Abstract:
An apparatus for generating a regulated direct current (DC) output voltage comprising:a DCâ€”DC converter coupled to a supply voltage, and being operative to generate a regulated output voltage derived from said supply voltage, said DCâ€”DC converter having a pulse width modulation generator which generates a PWM switching signal that switchably controls operation of a switching circuit containing first and second electronic power switching devices coupled between respective first and second power supply terminals, a common node thereof being coupled through an inductor element to an output voltage terminal; and a controller for controlling the operation of said PWM generator, said controller including a sense amplifier unit having a first input coupled to said first power supply terminal, a second input and an output, a current feedback resistor electrically coupled between said common output node and said second input of said sense amplifier unit, a variable impedance coupled to said output of said sense amplifier unit and to said second input of said sense amplifier unit, said variable impedance configured to vary in impedance in response to said output of said sense amplifier unit, and a current sensing and correction circuit that is operative to sense current flowing through said variable impedance as a sensed current, and to supply, to said controller, a correction current having a step-wise temperature-compensating relationship to said sensed current.