UC3572中文资料具有欠压锁定电路的负输出反激脉宽调制器数据手册TI规格书

描述 Description

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. Output current can be sensed and limited to a user determined maximum value. The UVLO circuit turns the chip off when the input voltage is below the UVLO threshold. In addition, a sleep comparator interfaces to the UVLO circuit to turn the chip off. This reduces the supply current to only 50uA, making the UC3572 ideal for battery powered applications.

特性 Features

• Simple Single Inductor Flyback PWM for Negative Voltage Generation
• Drives External PMOS Switch
• Contains UVLO Circuit
• Includes Pulse-by-Pulse Current Limit
• Low 50uA Sleep Mode Current