All trademarks are the property of their respective owners.
DescriptionThe UCCx808A devices are a family of BiCMOS push-pull, high-speed, low-power,pulse-width modulators. The UCCx808A contains all of the control and drive circuitry required foroff-line or DC-to-DC fixed frequency current-mode switching power supplies with minimal externalparts count.
The UCCx808A dual-output drive stages are arranged in a push-pull configuration. Bothoutputs switch at half the oscillator frequency using a toggle flip-flop. The dead time between thetwo outputs is typically 60 ns to 200 ns depending on the values of the timing capacitor andresistors, thus limiting each output stage duty cycle to less than 50%.
The UCCx808A family offers a variety of package options, temperature range options, andchoice of undervoltage lockout levels. The family has UVLO thresholds and hysteresis options foroff-line and battery-powered systems.
The UCCx808A is an enhanced version of the UCC3808 family. The significant difference isthat the A versions feature an internal discharge transistor from the CS pin to ground, which isactivated each clock cycle during the oscillator dead time. The feature discharges any filtercapacitance on the CS pin during each cycle and helps minimize filter capacitor values and currentsense delay.
Feature
- Dual-Output Drive Stages in Push-PullConfiguration
- Current-Sense Discharge Transistor to Improve DynamicResponse
- 130-μA Typical Starting Current
- 1-mA Typical RunCurrent
- Operation to 1 MHz
- Internal SoftStart
- On-Chip Error Amplifier With 2-MHz Gain BandwidthProduct
- On-Chip VDD Clamping
- Output Drive Stages Capable of500-mA Peak-Source Current, 1-A Peak-Sink Current
All trademarks are the property of their respective owners.
DescriptionThe UCCx808A devices are a family of BiCMOS push-pull, high-speed, low-power,pulse-width modulators. The UCCx808A contains all of the control and drive circuitry required foroff-line or DC-to-DC fixed frequency current-mode switching power supplies with minimal externalparts count.
The UCCx808A dual-output drive stages are arranged in a push-pull configuration. Bothoutputs switch at half the oscillator frequency using a toggle flip-flop. The dead time between thetwo outputs is typically 60 ns to 200 ns depending on the values of the timing capacitor andresistors, thus limiting each output stage duty cycle to less than 50%.
The UCCx808A family offers a variety of package options, temperature range options, andchoice of undervoltage lockout levels. The family has UVLO thresholds and hysteresis options foroff-line and battery-powered systems.
The UCCx808A is an enhanced version of the UCC3808 family. The significant difference isthat the A versions feature an internal discharge transistor from the CS pin to ground, which isactivated each clock cycle during the oscillator dead time. The feature discharges any filtercapacitance on the CS pin during each cycle and helps minimize filter capacitor values and currentsense delay.
