Patent ID: 7876078

Claim:
A switching power supply circuit comprising: sub-circuits comprising: a voltage reference generator for providing a voltage reference; a feedback resistor for sensing an output voltage of the power supply, said feedback resistor supplying a fraction of said output voltage; an integrator for integrating over time a difference between said reference voltage and said fraction of said output voltage, said integrator providing an integrator output; a voltage ramp generator providing a voltage ramp; a comparator for comparing said integrator output and said voltage ramp, said comparator providing a pulse width modulated signal; a switching element receiving said pulse width modulated signal, said switching element modulating current through an inductor in order to provide a regulated output voltage; and a monitoring circuit for monitoring said pulse width modulated signal over a period of time, said monitoring circuit providing a logical low signal when said pulse width signal is absent over said period of time; a capacitor/inverter circuit comprising an inverter, a switch, and a capacitor connected to an input of said inverter and said switch, said switch being operative to allow a voltage to be stored on said capacitor, said voltage being indicative of said regulated output voltage, said inverter comprising a signal output, said signal output providing an out of regulation signal when a difference between said voltage and said regulated voltage is sensed and said switch is inoperative; and a standby control circuit comprising disabling circuits, said disabling circuits disabling said sub-circuits when said logical low signal is detected permitting the switching power supply circuit to operate at a minimum current, a switch control circuit controlling at least said switch, said switch control circuit controlling said switch to be inoperative when said logical low signal is detected, and enabling circuits, said enabling circuits re-enabling said sub-circuits when said out of regulation signal is detected allowing the switching power supply to provide said regulated output.