High Performance Current Mode Controllers

The UC3844, UC3845 series are high performance fixed frequency current mode controllers. They are specifically designed for Off–Line and dc–to–dc converter applications offering the designer a cost effective solution with minimal external components. These integrated circuits feature an oscillator, a temperature compensated reference, high gain error amplifier, current sensing comparator, and a high current totem pole output ideally suited for driving a power MOSFET.

• Current Mode Operation to 500 kHz Output Switching Frequency

• Output Deadtime Adjustable from 50 to 70

• Automatic Feed Forward Compensation

• Latching PWM for Cycle–By–Cycle Current Limiting

• Internally Trimmed Reference with Undervoltage Lockout

• High Current Totem Pole Output

• Input Undervoltage Lockout with Hysteresis

• Low Startup and Operating Current

• Direct Interface with Motorola SENSEFET Products