CURRENT MODE PWM CONTROLLER
DESCRIPTION
The UTC UC3846 control IC offers all necessary features for accomplishment of fixed frequency, current mode control functions, however it contains the least external parts. The performance of this technique is superior to the others in better line regulation, enhanced load response characteristics while designing a simpler and easier control loop for design. It owns topological advantages of inherent pulse-by-pulse current limiting, automatic symmetry correction for push-pull converters, and the ability to parallel “power modules'' for equal current sharing. Protection loop includes soft start, built-in under-voltage lockout and programmable current limit. The shutdown circuitry can provide either a complete shutdown with automatic restart or the supply off-latch. In addition, many other features can also be available, including fully latched operation, double pulse suppression, deadline adjust, and a ±1% trimmed bandgap reference. The UTC UC3846 features low outputs in the OFF state.
FEATURES
* Built-in under-voltage lockout
* Soft start
* Shutdown function
* 500kHZ operation
* Feed forward compensation
* ±1% bandgap reference
* Programmable pulse-by-pulse current limiting
* Improved load response characteristics
* Parallel operation capability for modular power systems
* Differential current sense amplifier with wide common mode range
* Double pulse suppression
* 500mA (Peak) totem-pole outputs
* Automatic symmetry correction in push-pull configuration