A power supply regulator, comprising: a comparator having a first input coupled to sense a voltage representative of a current flowing through a switch during an on time of the switch, the comparator having a second input coupled to receive a variable current limit threshold that increases during the on time of the switch; a feedback circuit coupled to receive a feedback signal representative of an output voltage at an output of a power supply; and a control circuit coupled to generate a control signal in response to an output of the comparator and in response to an output of the feedback circuit, the control signal to be coupled to a control terminal of the switch to control switching of the switch. view more

The power supply regulator of claim 1 further comprising an oscillator having a first output to generate a sawtooth waveform, wherein the variable current limit threshold is generated in response to the sawtooth waveform.

A power supply regulator, comprising: a comparator having first and second inputs and an output, the first input of the comparator to sense a voltage developed by a switch, during an on time of the switch, the second input of the comparator coupled to receive a current limit threshold signal to increase during the on time of the switch; and a control circuit to generate a control signal in response to the output of the comparator, the control signal to be coupled to a control terminal of the switch to control switching of the switch to provide a power supply to have an output characteristic having an approximately constant output current below an output threshold voltage, the variable current limit threshold signal to vary between a first level and a second level during a time when the switch is to be on in response to the control signal. view more

The power supply regulator of claim 6 further comprising an oscillator to generate a sawtooth waveform, wherein variable current limit threshold signal is generated in response to the sawtooth waveform.

A digital frequency jittering circuit for varying the switching frequency of a power supply, comprising:</claim-text> an oscillator for generating a signal having a switching frequency, the oscillator having a control input for varying the switching ency; a digital to analog converter coupled to the control input for varying the switching frequency; and a counter coupled to the output of the oscillator and to the digital to analog converter, the counter causing the digital to analog converter to adjust the control input and to vary the switching frequency. view more

A frequency jittering circuit for varying a power supply switching frequency, comprising:</claim-text> an oscillator for generating a signal having a switching frequency, the oscillator having a control input for varying the switching frequency; and coupled to the control input for varying the switching frequency, including: one or more current sources coupled to the control input; and a counter coupled to the output of the oscillator and to the one or more current sources. view more

The regulation circuit of claim 11 further comprising a current limit circuit that provides a signal instructing said drive circuit to discontinue said drive signal when a current received at said first terminal of said regulation circuit is above a threshold level. view more