Patent ID: 7430130

Claim:
A switching converter for producing an output signal of voltage V OUT supplied through a signal path ( 89 ) to a variable load impedance ( 122 ) to produce a load voltage V DD across the load impedance, wherein the switching converter adjusts the output signal voltage to keep the load voltage near a set point voltage V SP selected by input first control data (D REF1 ), the switching converter comprising: a first power converter ( 96 ) powered by an input signal of voltage V IN for producing the output signal, wherein a ratio V OUT /V IN is a function of a duty cycle (D 1 ) of a pulse-width modulated first signal (V PWM1 ) supplied as input to the first power converter; a first pulse-width modulation circuit ( 94 ) for generating the first signal with its duty cycle (D 1 ) controlled by a first control signal (V C1 ) supplied as input to the pulse-width modulation circuit; a feedback control circuit ( 92 ), receiving the first control data and monitoring the load voltage, for adjusting the duty cycle of the first signal to keep the load voltage near the set point voltage selected by the first control data; and a power source ( 84 ), receiving second control data (D REF2 ) for supplying the input signal of voltage V IN to the first power converter, wherein V IN is selected by second control data (D REF2 ).