The UC1846/7 family of control devices provides all of the necessary features to implement fixed-frequency, current-mode control schemes while maintaining a minimum external parts count. The superior performance of this technique can be measured in improved line regulation, enhanced load response characteristics, and a simpler, easier-to-design control loop. Topological advantages include inherent pulse-by-pulse current limiting capability, automatic symmetry correction for push-pull converters, and the ability to parallelwhile maintaining equal current sharing. \
Protection circuitry includes built-in undervoltage lockout and programmable current limit, in addition to soft-start capability. A shutdown function is also available, which can initiate either a complete shutdown with automatic restart or latch the supply off.
Other features include fully-latched operation, double-pulse suppression, deadline adjust capability, and a ±1% trimmed band gap reference.
The UC1846 features low outputs in the OFF state, while the UCx847 features high outputs in the OFF state.
Feature
- Automatic Feedforward Compensation
- Programmable Pulse-by-Pulse Current Limiting
- Automatic Symmetry Correction in Push-Pull
Configuration - Enhanced Load Response Characteristics
- Parallel Operation Capability for Modular Power
Systems - Differential Current Sense Amplifier with Wide
Common Mode Range - Double-Pulse Suppression
- 500-mA (Peak) Totem-pole Outputs
- ±1% Band Gap Reference
- Undervoltage Lockout
- Soft-Start Capability
- Shutdown Terminal
- 500-kHz Operation
