LM2576
3.0 A, 15 V, Step−Down
Switching 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.
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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.
TO−220
TV SUFFIX
CASE 314B
1
5
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.
Heatsink surface connected to Pin 3
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 mA (typical) standby current. The
output switch includes cycle−by−cycle current limiting, as well as
thermal shutdown for full protection under fault conditions.
TO−220
T SUFFIX
CASE 314D
1
5
Pin 1.
V
in
2. Output
3. Ground
4. Feedback
5. ON/OFF
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
2
D PAK
D2T SUFFIX
CASE 936A
• Wide Input Voltage Range
1
5
• Requires Only 4 External Components
• 52 kHz Fixed Frequency Internal Oscillator
• TTL Shutdown Capability, Low Power Standby Mode
• High Efficiency
Heatsink surface (shown as terminal 6 in
case outline drawing) is connected to Pin 3
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 24 of this data sheet.
• Uses Readily Available Standard Inductors
• Thermal Shutdown and Current Limit Protection
• Moisture Sensitivity Level (MSL) Equals 1
• Pb−Free Packages are Available*
DEVICE MARKING INFORMATION
See general marking information in the device marking
section on page 24 of this data sheet.
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
*For additional information on our Pb−Free strategy
and soldering details, please download the
ON Semiconductor Soldering and Mounting
Techniques Reference Manual, SOLDERRM/D.
• Power Supply for Battery Chargers
Semiconductor Components Industries, LLC, 2004
1
Publication Order Number:
June, 2004 − Rev. 5
LM2576/D