A bi-directional voltage converter of a smart card includes switching elements connected between an input node and an output node and a start-up transistors whose channel width over channel length is smaller than a channel width over channel length of the switching element. The bi-directional voltage converter stores a driving voltage applied to an output node in a storage capacitor during a booting operation and provides the voltage stored in the storage capacitor to an input node. The bi-directional voltage converter may boost another driving voltage at the input node step-wisely and may perform bi-directional voltage converting with reduced occupied area and high efficiency.

A switching converter controller includes: a stopband controller having a stopband controller input and a stopband controller output, the stopband controller is configured to provide stopband information at the stopband controller output responsive to a reference signal; a pulse-frequency modulation (PFM) controller having a first PFM controller input, a second PFM controller input and a PFM controller output, the first PFM controller input configured to receive a feedback error signal, the second PFM controller input coupled to the stopband controller output, and the PFM controller configured to selectively adjust a clock signal at the PFM controller output based on the feedback error signal and the stopband information; and a driver circuit having a driver circuit input coupled to the PFM controller output and configured to receive the clock signal, and having a driver circuit output adapted to be coupled to a power stage switch.

In one embodiment, a method includes: enabling a pulse pair circuit of an integrated circuit in response to determining that a receiver associated with the integrated circuit is active; identifying that at least one comparator of a multi-output DC-DC converter trips, the DC-DC converter having a plurality of comparators each to compare a regulated voltage output by the DC-DC converter to a corresponding reference voltage; and generating, in the pulse pair circuit, a control pulse pair according to the tripped output, and driving a driver circuit of the DC-DC converter using the control pulse pair.

An embodiment PFC control circuit includes a first terminal providing a drive signal to an electronic switch of a boost converter, a second terminal receiving a feedback signal indicative of an output voltage generated by the boost converter, and a third terminal connected to a compensation network. An error amplifier generates a current as a function of the voltage at the second terminal and a reference voltage, wherein an output of the error amplifier is coupled to the third terminal. A driver circuit generates the drive signal as a function of the voltage at the third terminal, and selectively activates or deactivates the generation of the drive signal as a function of a burst mode enable signal. A detection circuit generates the burst mode enable signal as a function of the voltage at the second terminal.

Aspects of the disclosure provide for a circuit comprising a power converter controller. In an example, the power converter controller is configured to receive a signal representative of a current of a power converter, compare the signal representative of the current of the power converter to an error signal and generate a peak current detection signal having an asserted value when the signal representative of the current of the power converter is not less than the error signal. A state machine circuit is coupled the peak current detection circuit. The state machine circuit is configured to receive the peak current detection signal, a clock signal, and a timer signal and implement a state machine to generate at least one control signal for controlling a mode and a phase of operation of the power converter based on values of the peak current detection signal, the clock signal, and the timer signal.

A power converter, a synchronous power converter system and a method of determining switching frequency are provided. A processor is configured to output a synchronous clock signal corresponding to a first switching frequency. A plurality of first-stage power converters are coupled to the processor, and configured to generate a plurality of first output voltages corresponding to the first switching frequency according to the synchronous clock signal and a system voltage. At least one second-stage power converter is coupled to the processor and one of the plurality of first-stage power converters, and configured to generate a second output voltage corresponding to a second switching frequency according to the synchronous clock signal, a multiplied frequency control signal and one of the plurality of first output voltages. The second switching frequency is a multiple of the first switching frequency.

A power conversion device, which includes an insulation type full bridge converter and can switch a power transmission direction at a high speed, is provided. A DC/DC converter (10) constitutes a power conversion device, which operates as a first type converter that converts a voltage within a first range applied to a first input/output terminal pair into a voltage within a second range and outputs the voltage from a second input/output terminal pair or a second type converter that converts a voltage within the second range applied to the second input/output terminal pair into a voltage within the first range and outputs the voltage from the first input/output terminal pair, as a device that performs a predetermined state transition of the DC/DC converter (10) after waiting for a load current value of a primary or secondary side of a transformer (TR) becomes a value within a predetermined current value range.

A step up/down switching regulator converts an input voltage of an input terminal into a predetermined setting voltage in a step up/down manner and outputs the setting voltage as an output voltage from an output terminal. The step up/down switching regulator includes a bypass mode in which the input voltage is directly bypassed to the output terminal without performing a step up/down switching, and a step up/down switching mode in which the step up/down switching is performed. The step up/down switching regulator includes a step up/down output unit, a step up/down control unit, and a mode select terminal.

A control signal generator includes an error amplifier, a first comparator, a second comparator, a logic circuit and a pulse generator. The error amplifier has a first output, a first input, a second input and a first snooze input. The first comparator has a second output, a third input and a fourth input. The third input is coupled to the first output. The second comparator has a third output, a fifth input, a sixth input and a second snooze input. The fifth input is coupled to the third input. The logic circuit has a fourth output and logic circuit inputs, including a first logic circuit input coupled to the second output. The pulse generator has a fifth output and a seventh input. The seventh input is coupled to the fourth output. A snooze mode controller has a sixth output coupled to the first snooze input and the second snooze input.

A bi-directional voltage converter of a smart card includes switching elements connected between an input node and an output node and a start-up transistors whose channel width over channel length is smaller than a channel width over channel length of the switching element. The bi-directional voltage converter stores a driving voltage applied to an output node in a storage capacitor during a booting operation and provides the voltage stored in the storage capacitor to an input node. The bi-directional voltage converter may boost another driving voltage at the input node step-wisely and may perform bi-directional voltage converting with reduced occupied area and high efficiency.