MIC4575WU 데이터 시트보기 (PDF) - Micrel

부품명

상세내역

제조사

MIC4575WU

200kHz Simple 1A Buck Regulator

Micrel 

MIC4575

200kHz Simple 1A Buck Regulator

General Description

The MIC4575 is a series of easy to use fixed and

adjustable BiCMOS step-down (buck) switch-mode voltage

regulators. The 200kHz MIC4575 duplicates the pinout

and function of the 52kHz LM2575. The higher switching

frequency may allow up to a 2:1 reduction in output filter

inductor size.

The MIC4575 is available in 3.3V, and 5V fixed output

versions or a 1.23V to 20V adjustable output version. Both

versions are capable of driving a 1A load with excellent

line and load regulation.

The feedback voltage is guaranteed to ±2% tolerance for

adjustable versions, and the output voltage is guaranteed

to ±3% for fixed versions, within specified voltages and

load conditions. The oscillator frequency is guaranteed to

±10%.

In shutdown mode, the regulator draws less than 200µA

standby current. The regulator performs cycle-by-cycle

current limiting and thermal shutdown for protection under

fault conditions.

This series of simple switch-mode regulators requires a

minimum number of external components and can operate

using a standard series of inductors. Frequency comp-

ensation is provided internally.

The MIC4575 is available in TO-220 (T) and TO-263 (U)

packages for the industrial temperature range.

Data sheets and support documentation can be found on

Micrel’s web site at www.micrel.com.

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 1A 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% typical)

• Standard inductors and capacitors are25% of typical

LM2575 values

• Thermal shutdown

• Overcurrent protection

• 100% electrical thermal limit burn-in

Applications

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

• Efficient pre-regulator for linear regulators

• On-card switching regulators

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

• Battery charger

• Negative boost converter

• Step-down 6V to 3.3V for Intel Pentium® and similar

microprocessors

___________________________________________________________________________________________________________

Typical Application

Shutdown

Enable

8V to 24V

C1

150µF

35V

5 SHDN

SW 2

MIC4575-5.0_T

1 VIN

FB 4

GND

3

L1

68µH

D1

1N5819

5.0V/1A

C2

330µF

16V

Fixed Regulator

Adjustable Regulator

Pentium is a registered trademark of Intel Corporation

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com

July 2009

1

M9999-072909

Share Link: