1 Features

• 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%.

1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic