Device
Operating
Temperature Range
Package
LM2576
EASY SWITCHER
3.0 A STEP–DOWN
VOLTAGE REGULATOR
ORDERING INFORMATION
LM2576T–XX
LM2576TV–XX
TJ = –40° to +125°C
Straight Lead
Vertical Mount
D2T SUFFIX
PLASTIC PACKAGE
CASE 936A
(D2PAK)
Order this document by LM2576/D
T SUFFIX
PLASTIC PACKAGE
CASE 314D
TV SUFFIX
PLASTIC PACKAGE
CASE 314B
LM2576D2T–XX
Surface Mount
XX = Voltage Option, i.e. 3.3, 5, 12, 15 V; and ADJ for
Adjustable Output.
SEMICONDUCTOR
TECHNICAL DATA
1
5
1
5
1
5
DEVICE TYPE/NOMINAL OUTPUT VOLTAGE
LM2576–3.3
LM2576–5
LM2576–12
LM2576–15
LM2576–ADJ
3.3 V
5.0 V
12 V
15 V
1.23 V to 37 V
Pin 1. Vin
2. Output
3. Ground
4. Feedback
5. ON/OFF
Heatsink surface
connected to Pin 3.
Heatsink surface (shown as terminal 6 in case outline
drawing) is connected to Pin 3.
1
MOTOROLA ANALOG IC DEVICE DATA
Easy Switcher 3.0 A
Step-Down Voltage Regulator
The LM2576 series of regulators are monolithic integrated circuits ideally
suited for easy and convenient design of a step–down switching regulator
(buck converter). All circuits of this series are capable of driving a 3.0 A load
with excellent line and load regulation. These devices are available in fixed
output voltages of 3.3 V, 5.0 V, 12 V, 15 V, and an adjustable output version.
These regulators were designed to minimize the number of external
components to simplify the power supply design. Standard series of
inductors optimized for use with the LM2576 are offered by several different
inductor manufacturers.
Since the LM2576 converter is a switch–mode power supply, its efficiency
is significantly higher in comparison with popular three–terminal linear
regulators, especially with higher input voltages. In many cases, the power
dissipated is so low that no heatsink is required or its size could be reduced
dramatically.
A standard series of inductors optimized for use with the LM2576 are
available from several different manufacturers. This feature greatly simplifies
the design of switch–mode power supplies.
The LM2576 features include a guaranteed
±4% tolerance on output
voltage within specified input voltages and output load conditions, and
±10%
on the oscillator frequency (
±2% over 0°C to 125°C). External shutdown is
included, featuring 80
A (typical) standby current. The output switch
includes cycle–by–cycle current limiting, as well as thermal shutdown for full
protection under fault conditions.
Features
3.3 V, 5.0 V, 12 V, 15 V, and Adjustable Output Versions
Adjustable Version Output Voltage Range, 1.23 to 37 V ±4% Maximum
Over Line and Load Conditions
Guaranteed 3.0 A Output Current
Wide Input Voltage Range
Requires Only 4 External Components
52 kHz Fixed Frequency Internal Oscillator
TTL Shutdown Capability, Low Power Standby Mode
High Efficiency
Uses Readily Available Standard Inductors
Thermal Shutdown and Current Limit Protection
Applications
Simple High–Efficiency Step–Down (Buck) Regulator
Efficient Pre–Regulator for Linear Regulators
On–Card Switching Regulators
Positive to Negative Converter (Buck–Boost)
Negative Step–Up Converters
Power Supply for Battery Chargers
Motorola, Inc. 1999
Rev 1, 07/1999