Features Automatic Feedforward Compensation Programmable Pulse-by-Pulse Current Limiting Automatic Symmetry Correction in Push-Pull Configuration Enhanced Load Response Characteristics % Bandgap Reference Undervoltage Lockout Soft-Start Capability Shutdown Terminal 500kHz Operating Instructions The UC3846 control IC provides all the necessary features to implement a fixed frequency, current mode control scheme while maintaining a minimal external part count. The superior performance of this technology can be measured by improved line regulation, enhanced load response characteristics, and design of simple control loops. Topological advantages include inherent pulse-by-pulse current limiting capability, automatic symmetry correction of push-pull converters, and the ability to parallel “power modules” while maintaining equal current sharing. In addition to the soft-start function, protection circuits include built-in undervoltage lockout and programmable current limit. A shutdown function is also available, which can initiate a complete shutdown or power down with an automatic restart. Other features include fully latched operation, dual-pulse rejection, dead-time adjustment capability, and a ±2% trimmed bandgap reference. The UC3846 has a low output in the shutdown state.

internal block diagram,

In some applications, a small PC filter may be required to reduce switching transients on the differential input, allowing long-range noise-free sensing.

Mechanical size package