High Speed Single−Ended PWM Controller

The MC34023 series are high speed, fixed frequency, single−ended pulse width modulator controllers optimized for high frequency operation. 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, a wide bandwidth error amplifier, a high speed current sensing comparator, and a high current totem pole output ideally suited for driving a power MOSFET.

Features

• 50 ns Propagation Delay to Output

• High Current Totem Pole Output

• Wide Bandwidth Error Amplifier

• Fully−Latched Logic with Double Pulse Suppression

• Latching PWM for Cycle−By−Cycle Current Limiting

• Soft−Start Control with Latched Overcurrent Reset

• Input Undervoltage Lockout with Hysteresis

• Low Startup Current (500 μA Typ)

• Internally Trimmed Reference with Undervoltage Lockout

• 90 Maximum Duty Cycle (Externally Adjustable)

• Precision Trimmed Oscillator

• Voltage or Current Mode Operation to 1.0 MHz

• Functionally Similar to the UC3823

• Pb−Free Packages are Available*