Multi-slope startup voltage regulator system

A voltage regulator circuit comprising:

• switch circuitry coupled between a voltage input and a regulated output, the switch circuitry including a switch input;
• feedback circuitry having an input coupled to the regulated output and having a feedback output, the feedback circuitry having a reference voltage input adapted to receive a reference voltage that increases linearly at a first slope in a first stage and at a second slope in a second stage, the second slope being different from the first slope;
• gate driver circuitry having an input coupled to the feedback output and having a switch output coupled to the switch input;
• and
• sampling circuitry having an input coupled to the regulated output, the sampling circuitry sampling a voltage and a current at the regulated output during the first stage and during the second stage.

A process for starting a voltage regulator comprising:

• receiving a reference voltage at an input of feedback circuitry of the voltage regulator, the reference voltage having a first stage and having a second stage after the first stage, the reference voltage in the first stage having a first slope that increases linearly, the reference voltage in the second stage having a second slope that increases linearly, the second slope increasing over the first slope, the feedback circuitry producing a feedback signal that follows the reference voltage;
• operating switch circuitry based on the feedback signal to regulate an output current and an output voltage, the operating including regulating the output voltage to have different output voltage slopes in the respective stages;
• measuring the slopes of the output voltages in the respective stages;
• and
• calculating a change in output capacitance based on the measured slopes of the output voltages for the respective stages.

An integrated circuit comprising:

• (a) a regulated voltage input, an inductor current input, a reference voltage input, and a driver output;
• (b) compensation circuitry having a first input coupled to the regulated voltage input, having a second input coupled to the reference voltage input, and having an error voltage output;
• (c) ramp generator circuitry having a ramp output;
• (d) comparator circuitry having a first input coupled to the error voltage output and the ramp output, having a second input coupled to the inductor current input, and having a comparison output;
• and
• (e) controller circuitry having an input coupled to the inductor current input, having an input coupled to the comparison output, and having an output coupled to the driver output.