UC2572NG4

开关控制器 Neg-Out Flyback Pls Width Modulator

DESCRIPON

The UC3572 is a negative output flyback pulse width modulator which converts a positive input voltage to a regulated negative output voltage. The chip is optimized for use in a single inductor negative flyback switching converter employing an external PMOS switch. The block diagram consists of a precision reference, an error amplifier configured for voltage mode operation, an oscillator, a PWM comparator with latching logic, and a 0.5A peak gate driver. The UC3572 includes an undervoltage lockout circuit to insure sufficient input supply voltage is present before any switching activity can occur, and a pulse-by-pulse current limit.

FEATURES

• Simple Single Inductor Flyback PWM for Negative Voltage Generation

• Drives External PMOS Switch

• Contains UVLO Circuit

• Includes Pulse-by-Pulse Current Limit

• Low 50µA Sleep Mode Current