Soft-start time control circuit

摘要

A control circuit for controlling a soft-start time of a DC power supply includes a digital potentiometer, a first drive circuit, and a controller. The digital potentiometer includes a first potentiometer. The first drive circuit includes a first driver, a first MOSFET, and a first charge capacitor. The first driver charges the first charge capacitor via the first potentiometer when the DC power supply is first switched on, and the first MOSFET is switched on to connect the DC power supply to the load when the first charge capacitor is fully charged. The controller regulates resistance of the first potentiometer to regulate a charge time constant of the first charge capacitor, enabling a gradual rise in voltage supplied, from approximately zero to full power, within a desired period of time.

主权项

1. A control circuit for controlling a soft-start time of a direct current (DC) power supply, comprising:
a digital potentiometer comprising a first potentiometer; a first drive circuit comprising a first driver, a first metal-oxide-semiconductor field-effect transistor (MOSFET), and a first charge capacitor; and a controller electronically connected to the digital potentiometer; wherein the first MOSFET is electronically connected between the output of the DC power supply and a load, and is electronically connected to the driver via the first potentiometer; the first charge capacitor is electronically connected to a node between the first MOSFET and the first potentiometer; the first driver is electronically connected to the DC power supply, the first driver charges the first charge capacitor via the first potentiometer when the DC power supply is first switched on, and the first MOSFET is switched on to connect the DC power supply to the load when the first charge capacitor is fully charged; the controller regulates resistance of the first potentiometer to regulate a charge time constant of the first charge capacitor, enabling a gradual rise in voltage supplied, from approximately zero to full power, within a desired period of time.