UC2525ADWTR 开关控制器

UC2525ADWTR
1 Features UC2525ADWTR

1• 8-V to 35-V Operation

• 5.1-V Reference Trimmed to 1%

• 100-Hz to 500-kHz Oscillator Range

• Separate Oscillator Sync Terminal

• Adjustable Dead-Time Control

• Internal Soft Start

• Pulse-by-Pulse Shutdown

• Input Undervoltage Lockout With Hysteresis

• Latching PWM to Prevent Multiple Pulses

• Dual Source and Sink Output Drivers

2 Applications UC2525ADWTR

• Off-Line and DC/DC Power Supplies

• Converters Using Voltage Mode

• Single-Ended or Two-Switch Topology Designs

• Solar Inverters

• Welding Inverters

• Motor Control

• Battery Chargers

3 DescriptionUC2525ADWTR

The UC1525A/1527A series of pulse width modulator

integrated circuits are designed to offer improved

performance and lowered external parts count when

used in designing all types of switching power

supplies. The on-chip 5.1-V reference is trimmed to

1% and the input common-mode range of the error

amplifier includes the reference voltage, eliminating

external resistors. A sync input to the oscillator allows

multiple units to be slaved or a single unit to be

synchronized to an external system clock. A single

resistor between CT and the discharge terminals

provides a wide range of dead-time adjustment.

These devices also feature built-in soft-start circuitry

with only an external timing capacitor required. A

shutdown terminal controls both the soft-start circuitry

and the output stages, providing instantaneous turn

off through the PWM latch with pulsed shutdown, as

well as soft-start recycle with longer shutdown

commands.