UC3846N

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 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, 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.

Applications

• Telecommunication Power Converters
• Industrial Power Converters

Key features

• 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