High speed, fixed frequency, single ended pulse width modulator

The MC34023 series is a high speed, fixed frequency, single ended pulse width modulator controller optimized for high frequency operation. Designed specifically for offline and DC-to-DC converter applications, they provide designers with a cost effective solution with minimal external components.

These ics feature an oscillator, a temperature compensation reference, a broadband wide error amplifier, a high-speed current sensing comparator, and a high-current totem pole output well suited to drive power mosFETs.

Also included are protection features including input and reference undervoltage locks, per lag, cycle duration streams, and latches for monopulse metering. The flexibility of the series allows it to be easily configured for current mode or voltage mode control.

Features

● Propagation delay to output is 50ns
● High current totem pole output
● Broadband wide error amplifier
● Full − latch logic with dual pulse suppression
● Locks PWM cycle current limits
● Soft start control, latch overcurrent reset
● Input undervoltage lock lag
● Low starting current (500a type)
● Internal trimming reference undervoltage locking
● 90% maximum duty cycle (externally adjustable)
● Fine tuning oscillator
● Voltage or current mode operation to 1.0 MHz
● Functions similar to the UC3823
● These are lead-free devices