1FEATURES
• Automatic Feed-Forward 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
• Undervoltage Lockout
• Soft-Start Capability
• Shutdown Terminal

DESCRIPTION
The UC1846 control IC 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 parallel power modules, while 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 and deadline adjust capability.
The UC1846 features low outputs in the OFF state.