Description

5V, 12V, 15V and a versatile Adjustable output

a minimum number of external components.

frequency

oscillator.

replacement for popular three-terminal linear regulators,

and is requiring a smaller heat sink or even no heat sink.

performs well with standard

inductors from

several manufacturers, and simplifying the design of

switch-mode power supplies.

tolerance on output voltage within specified input voltages

protection under fault conditions.

TYPICAL APPLICATION

Features

3.3V, 5V, 12V, 15V and

Adjustable version output voltage range

1A output current

Requires Only 4 External Components

High Efficiency

TTL shutdown capability and low power

standby mode

Thermal shutdown, current limit protection

Uses standard inductors

52 kHz fixed frequency internal oscillator

7V - 40V

Unregulated

DC Input

+

C

IN

100 µF

+V

IN

1

5

3

4

2

GND

D1

1N5819

Output

330 µH

L1

Feedback

C

OUT

330 µF

5.0V, 1A

Regulated

Output

+

ON / OFF

Application

Pre-regulator for linear regulators

High-efficiency step-down buck regulator

On-card/ board switching regulators

Positive to negative converter (buck-boost

)

of regulators provides all the active functions

for a step- down (buck) switching regulator, and drives

1A load with excellent line and load regulation.

is available in fixed output volt ages of 3.3V,

version. These regulators are simple to use and require

Features include internal frequency compensation and

a fixed-

and output load conditions, and ±10% on the oscillator

frequency.

External

shutdown

is

included

with

50

uA(typical)

standby current. The output switch has cycle-by-cycle

current limiting as well as thermal shutdown for full

1.23V to 37V ±4% max over line and load

conditions

Adjustable output

versions

LM2575

LM2575

LM2575

LM2575 guarantee +/-4%

LM2575 high-efficiency

LM2575 -5.0

LM2575 1.0A Step - Down Voltage Switching Regulators