Abstract:
A switched capacitor converter includes plural switch units. The switch units are configured to switch a coupling relationship of a capacitor between a first power and a second power, wherein at least one of the switch units includes a switch circuit. The switch circuit includes a first switch, a second switch, and a switch driving circuit, wherein the conduction resistance of the first switch is greater than the conduction resistance of the second switch, and the parasitic capacitance of the first switch is less than the parasitic capacitance of the second switch. The switch driving circuit turns on the first switch before the second switch is turned on and/or turns off the first switch after the second switch is turned off, such that the switching loss of the switch circuit is less than a predetermined target value.
Abstract:
A switching power conversion circuit includes a conversion capacitor, a capacitive power conversion circuit, an inductor, an inductive power conversion circuit and a switching control circuit. The capacitive power conversion circuit includes plural switching devices for generating an intermediate voltage which is in a predetermined proportional relationship to the input voltage. The inductive power conversion circuit includes plural switching devices for converting the intermediate voltage to an output voltage. The plural switching devices of the capacitive power conversion circuit and the inductive power conversion circuit switch the conversion capacitor and the inductor periodically according to the duty ratio of the switching control signal generated by the switching control circuit. The capacitive power conversion circuit and the inductive power conversion circuit share one of the plural switching devices.
Abstract:
A multi-level switching power converter includes a multi-level power stage circuit which converts an input power to an output power. The power stage circuit includes an inductor, a conversion capacitor and plural power switches. The controller circuit controls the multi-level power stage circuit and includes: a feedback pulse generator circuit which generates a trigger pulse; a first timer circuit and a second timer circuit which determine a first time period and a second time period respectively according to the trigger pulse; and an adjusting circuit which adjusts the first time period according to a difference between the voltage across the conversion capacitor and a reference voltage such that an average of the voltage across the conversion capacitor is substantially equal to a level of the reference voltage.
Abstract:
A LED driver using a PWM signal for dimming control includes a power converter and a current regulator. The power converter provides an output voltage and a load current for a plurality of LEDs. The current regulator provides a load current dependent signal for the power converter to speed up load transient response caused by variation of the load current, to reduce the ripple of the output voltage, and thereby to avoid audio noise during PWM dimming.
Abstract:
Serially connected low voltage transistors are used to replace a high voltage transistor in a voltage conversion circuit for a driver, or parallel connected sub-transistors are used to establish a high voltage transistor having an effective size dynamically adjusted according to loading of the driver, to reduce switching loss and thereby improve the efficiency of the driver.
Abstract:
A power conversion system includes: first and second switches, a switching power converter, a battery switch and a conversion control circuit. In an external power mode, the first and second switches are controlled to generate an intermediate power from a first power and generate a second power from the intermediate power for powering an external load. In a battery power mode, the conversion control circuit controls the battery switch, the switching power converter and the second switch to generate a system power from a battery power, convert the system power to generate the intermediate power and generate the second power from the intermediate power. In the external power mode, the switching power converter is controlled to enter the battery power mode when the intermediate voltage is reduced to a transient state threshold, wherein a minimum voltage level of the intermediate power is close to a minimum voltage regulation level.
Abstract:
A multi-mode power system includes a battery module, a first conversion circuit, and a second conversion circuit. The battery module includes a battery path switch and a battery group. The first conversion circuit includes switches and a first capacitor, wherein the switches include the battery path switch. The multi-mode power system operates in one of plural operation mode combinations, wherein when the first conversion circuit operates in a first outgoing mode or a first bypass mode, the second conversion circuit operates in a second incoming mode, a second outgoing mode, or a second bypass mode; when the first conversion circuit operates in a first incoming mode, the second conversion circuit operates in the second incoming mode or the second bypass mode.
Abstract:
A power conversion circuit includes an N-level PWM power converter and a switching capacitor power converter. The N-level PWM power converter includes shared switches shared with the switching capacitor power converter, and PWM switches. In an N-level PWM mode, the shared switches and the PWM switches periodically switch an inductor and a capacitor, to execute power conversion between a first power and a second power by N-level PWM switching operation. The switching capacitor power converter includes the shared switches and auxiliary switches. In a capacitive conversion mode, the shared switches and the auxiliary switches periodically switch the capacitor, to execute power conversion between the first power and the second power by capacitive power conversion operation. In the capacitive conversion mode, a portion of the plural PWM switches are always OFF such that one end of the inductor is floating.
Abstract:
A switched capacitor converter circuit includes: plural capacitors and plural switches which switch the connections of the plural capacitors periodically. In a first period, the plural switches control a first capacitor to be electrically connected between a first power and a second power, and control a second capacitor and a third capacitor to be electrically connected in series between the second power and a ground level. In a second period, the plural switches control the first capacitor and the second capacitor to be electrically connected in series between the second power and the ground, and control the third capacitor and the second capacitor to be electrically connected in parallel with the second power, thereby a second current of the second power is 4 times of a first current of the first power.
Abstract:
A switched capacitor converter circuit includes: plural capacitors and plural switches which switch the connections of the plural capacitors periodically. In a first period, the plural switches control a first capacitor to be electrically connected between a first power and a second power, and control a second capacitor and a third capacitor to be electrically connected in series between the second power and a ground level. In a second period, the plural switches control the first capacitor and the second capacitor to be electrically connected in series between the second power and the ground, and control the third capacitor and the second capacitor to be electrically connected in parallel with the second power, thereby a second current of the second power is 4 times of a first current of the first power.