General Description

The MIC4574 is a series of easy to use fixed and adjustable BiCMOS step-down (buck) switch-mode voltage regulators. The 200kHz MIC4574 duplicates the pinout and function of the 52kHz LM2574. The higher switching frequency may allow up to a 2:1 reduction in output filter inductor size.

特性 Features

? Fixed 200kHz operation

? 3.3V, 5V, and adjustable output versions

? Voltage over specified line and load conditions:

Fixed version: ±3 max. output voltage

Adjustable version: ±2 max. feedback voltage

? Guaranteed 0.5A switch current

? Wide 4V to 24V input voltage range

? Wide 1.23V to 20V output voltage range

? Requires minimum external components

? < 200μA typical shutdown mode

? 75 efficiency (adjustable version > 75 typ.)

? Standard inductors and capacitors are 25 of typical LM2574 values

? Thermal shutdown

? Overcurrent protection

? 100 electrical thermal limit burn-in

Applications

? Simple high-efficiency step-down (buck) regulator

? Efficient preregulator for linear regulators

? On-card switching regulators

? Positive-to-negative converter (inverting buck-boost)

? Isolated flyback converter using minimum external components

? Negative boost converter