Abstract: A controller for a switched mode power converter includes limit-to-valley ratio circuitry, an on-time generator, and a drive circuit. The limit-to-valley ratio circuitry is coupled to generate a ratio signal in response to sensing a switch current of a switch that regulates an output of the switched mode power converter. The ratio signal is representative of a time ratio between a first length of time that the switch current is at or above a switch current limit and a second length of time that the switch current is at or below a switch current valley that is a portion of the switch current limit. The on-time generator is coupled to vary a switch on-time signal in response to receiving the ratio signal. The drive circuit is coupled to output a drive signal to a control terminal of the switch in response to receiving the switch on-time signal.

Abstract: A controller for a switched mode power converter includes limit-to-valley ratio circuitry, an on-time generator, and a drive circuit. The limit-to-valley ratio circuitry is coupled to generate a ratio signal in response to sensing a switch current of a switch that regulates an output of the switched mode power converter. The ratio signal is representative of a time ratio between a first length of time that the switch current is at or above a switch current limit and a second length of time that the switch current is at or below a switch current valley that is a portion of the switch current limit. The on-time generator is coupled to vary a switch on-time signal in response to receiving the ratio signal. The drive circuit is coupled to output a drive signal to a control terminal of the switch in response to receiving the switch on-time signal.

Abstract: A controller for use in a power converter includes a gate drive circuit coupled to generate a control signal to switch a power switch of the power converter. A zero current detection circuit is coupled to a multifunction pin coupled to receive a multifunction signal that is representative of an input voltage of the power converter when the power switch is on, and representative of an output voltage of the power converter when the power switch is off. The zero current detection circuit is coupled to generate a zero current detection signal. An overvoltage detection circuit is coupled to receive the multifunction signal and a state signal representative of a state of the power switch to generate in response to the state signal and the multifunction signal a line overvoltage signal and an output over voltage signal coupled to be received by the gate drive circuit.

Abstract: A controller for use in a power converter includes a gate drive circuit coupled to generate a control signal to switch a power switch of the power converter. A zero current detection circuit is coupled to a multifunction pin coupled to receive a multifunction signal that is representative of an input voltage of the power converter when the power switch is on, and representative of an output voltage of the power converter when the power switch is off. The zero current detection circuit is coupled to generate a zero current detection signal. An overvoltage detection circuit is coupled to receive the multifunction signal and a state signal representative of a state of the power switch to generate in response to the state signal and the multifunction signal a line overvoltage signal and an output over voltage signal coupled to be received by the gate drive circuit.

Abstract: A switching circuit with reverse current prevention for use in a Buck converter includes a power switch coupled to a coupling node, which is an interconnection point of a power switch, an inductor and a freewheeling diode of the Buck converter. The inductor is coupled between the coupling node and an output of the Buck converter, and the freewheeling diode is coupled between coupling node and an output return of the Buck converter. A controller is coupled to receive a feedback signal to control switching of the power switch to regulate a transfer of energy from the input to the output of the Buck converter. A reverse current prevention circuit is coupled to detect a reverse current condition of the power switch to generate an inhibit signal to inhibit the power switch from receiving a drive signal to prevent a reverse current through the power switch.