Microchip | MIC4574YN

The MIC4574YN is a series of easy to use fixed and adjustable BiCMOS step-down (buck) switch-mode voltage regulators. The 200 kHz MIC4574 duplicates the pinout and function of the 52 kHz LM2574. The higher switching frequency may allow up to a 2:1 reduction in output filter inductor size.

The MIC4574 is available in 3.3 V, and 5 V fixed output versions or a 1.23 V to 20 V adjustable output version. Both versions are capable of driving a 0.5  A load with excellent line and load regulation.

Features:

• Fixed 200kHz operation
• 3.3 V, 5  V, and adjustable output versions Voltage over specified line and load conditions:
• Fixed version: ±3% max. output voltage
• Adjustable version: ±2% max. feedback voltage
• Guaranteed 0.5 A switch currentWide 4 V to 24 V input voltage range
• Wide 1.23 V to 20 V output voltage range
• Requires minimum external components
• < 200 μA typical shutdown mode
• 75% efficiency (adjustable version > 75% typ.)
• 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