1 Features

1• Dual Output Drive Stages in Push-Pull

Configuration

• 130-μA Typical Starting Current

• 1-mA Typical Run Current

• Operation to 1-MHz

• Internal Soft-Start

• On-Chip Error Amplifier With 2-MHz Gain

Bandwidth Product

• On-Chip VDD Clamping

• Output Drive Stages Capable Of 500-mA Peak

Source Current, 1-A Peak Sink Current

2 Applications

• Server and Desktop Power Supplies

• Telecom Power Supplies

• DC-DC Converters

• Switched-Mode Power Supplies

3 Description

The UCCx808-x is a family of BiCMOS push-pull,

high-speed, low-power, pulse-width modulators. The

UCCx808 contains all of the control and drive circuitry

required for offline or DC-to-DC fixed frequency

current-mode switching power supplies with minimal

external parts count.

The UCCx808-x dual output drive stages are

arranged in a push-pull configuration. Both outputs

switch at half the oscillator frequency using a toggle

flip-flop. The dead time between the two outputs is

typically 60 ns to 200 ns depending on the values of

the timing capacitor and resistors, thus limiting each

output stage duty cycle to less than 50%.