Power Integrations, Inc.

Sundaresan Sundararaj

Tiziano Pastore

Balu Balakrishnan

Yury Gaknoki

Zhao-Jun Wang

Lance M Wong

Zongqi Hu

Arthur Brian Odell

Peter Vaughan

Jose Requinton Del Carmen, Jr

Qing McIntosh

A controller comprising a regulation circuit and a frequency request circuit. The regulation circuit configured to receive a signal representative of an output and a reference representative of a desired value of the output, the regulation circuit configured to output a regulation signal in response to a difference between the signal and the reference. The frequency request circuit configured to receive the regulation signal and outputs an increment signal representative of a request to increase a switching frequency and a decrement signal representative of a request to decrease the switching frequency in response to the regulation signal. The frequency request circuit configured to assert the increment signal when the output is less than the desired value for a duration longer than a first period and assert the decrement signal when the output is greater than the desired value for a duration longer than a second period.

Controller with frequency request circuit

A controller for use in a power converter includes a secondary controller coupled to receive a feedback signal representative of an output of the power converter to generate d a request signal. A primary controller is coupled to receive the request signal to generate a primary drive signal. The primary drive signal is coupled to control switching of a power switch to control a transfer of energy from the input to the output of the power converter. A frequency to on-time converter included in the primary controller is coupled to receive the request signal. The frequency to on-time converter is coupled to control the duration of on-time pulses included in the primary drive signal in response to a period of the request signal.

Controller with frequency to on-time converter

A controller for use in a power converter comprising a comparator, request control, and foldback control. The comparator configured to receive a feedback signal representative of an output of the power converter and a first regulation reference representative of a target value for the output, and in response to the comparison of the feedback signal and the first regulation reference, generate a first regulation signal. Request control configured to receive the first regulation reference, and output a request signal with request events. Foldback control configured to receive the first regulation signal to generate the first regulation reference, the foldback control further configured to sense a foldback or fault condition if the feedback signal is less than the first regulation reference for a threshold duration of time, the foldback control further configured to vary the first regulation reference in response to the sensed foldback or fault condition to reduce the output.

Closed loop foldback control

A power conversion system includes a switch mode power converter including a switch coupled to regulate an output voltage to a regulation value in response to a feedback signal. A controller is coupled to deliver a gate drive signal to the switch during an enabled control condition. The controller is further coupled to inhibit the gate drive signal to the switch during an inhibited control condition. A duty cycle state machine included in controller is coupled to adjust a duty cycle of the gate drive signal according to a plurality of discrete duty cycle states.

Apparatus and methods for controlling a switch mode power converter using a duty cycle state machine

A controller for use in a power converter comprising a request control circuit coupled to receive a feedback signal representative of an output of the power converter. The request control circuit is coupled to generate a request signal for controlling a power switch. The request signal can include a synchronization signal in response to the feedback signal and a jitter average signal. The synchronization signal is generated by the request transmitter circuit and corresponds to an average on time for controlling the power switch.

Frequency jitter for a power converter

A controller for use in a power converter includes a comparator configured to compare a sense signal representative of an amount of energy delivered to an output of the power converter, to a target value. An update clock generator configured to receive the sense signal and to generate a clock signal having a clock frequency in response to the sense signal. A request control coupled to the comparator and to the update clock generator, the request control configured to generate a request signal having a request frequency that is responsive to an output of the comparator and that controls an operational state of a power switch of the power converter. The request control further configured to update a rate at which the request frequency of the request signal is responsive to the clock frequency of the clock signal.

Controller with variable sampling generator

A controller for use in a power converter includes comparator coupled to generate a regulation signal in response to a regulation reference and an output sense signal. The output sense signal is representative of an output of the power converter. A drive signal generator is coupled to the comparator to generate a drive signal to control switching of a power switch of the power converter in response to the regulation signal. The drive signal generator is further coupled to generate an operation sense signal representative of an operational state of the power switch. A foldback control is coupled to the comparator and the drive signal generator to generate the regulation reference in response to the regulation signal and the operation sense signal.

A controller for use in a switched mode power converter includes a comparator coupled to compare an output sense signal representative of an output of the switched mode power converter to a target value. An update clock generator is coupled to generate a clock signal having a clock frequency in response to the output sense signal. A request control is coupled to generate a request signal having a request frequency in response to an output of the comparator and the clock signal to control an operational state of a power switch of the switched mode power converter. A speed at which the request control updates the request frequency of the request signal is responsive to the clock frequency of the clock signal.

A controller for use in a switched mode power converter includes a comparator coupled to compare an output sense signal representative of an output of the switched mode power converter to a target value. A ripple compensation block is coupled to generate a compensation signal in response to the output sense signal. The compensation signal is a fraction of the output sense signal. A request control is coupled to generate a request signal having a request frequency in response to an output of the comparator and a clock signal to control an operational state of a power switch of the switched mode power converter. The request control is further coupled to receive the compensation signal to modulate the request frequency of the request signal with the compensation signal in response to the output of the comparator to provide ripple compensation at the output of the switched mode power converter.

Controller with ripple compensation

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.

Reverse current blockage through buck controller block

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.

Limit-to-valley ratio circuitry in power converters

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.

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Union City, CA, United States of America

Sundaresan Sundararaj