LM2576 Series

3A Step-Down SMPS Regulator

Catalog

3A Step-Down SMPS Regulator

Part	Supplier Device Package	Topology	Voltage - Input (Min) [Min]	Number of Outputs	Operating Temperature [Min]	Operating Temperature [Max]	Package / Case	Output Configuration	Function	Output Type	Frequency - Switching	Current - Output	Mounting Type	Voltage - Output (Min/Fixed)	Output Type	Voltage - Output (Max)
Microchip Technology LM2576-5.0WU-TR	TO-263-5	Buck	4 V	1	-40 °C	125 ¯C	D2PAK (5 Leads + Tab) TO-263-6 TO-263BA	Positive	Step-Down	1.81 mOhm	52 kHz	3 A	Surface Mount	5 V
Microchip Technology LM2576-12BT	TO-220-5	Buck	4 V	1	-40 °C	125 ¯C	TO-220-5	Positive	Step-Down	1.81 mOhm	52 kHz	3 A	Through Hole	12 V
Microchip Technology LM2576-3.3BU	TO-263-5	Buck	4 V	1	-40 °C	125 ¯C	D2PAK (5 Leads + Tab) TO-263-6 TO-263BA	Positive	Step-Down	1.81 mOhm	52 kHz	3 A	Surface Mount	3.3 V
Microchip Technology LM2576BU	TO-263-5	Buck	4 V	1	-40 °C	125 ¯C	D2PAK (5 Leads + Tab) TO-263-6 TO-263BA	Positive	Step-Down		52 kHz	3 A	Surface Mount	1.23 V	Adjustable	37 V
Microchip Technology LM2576-3.3BT	TO-220-5	Buck	4 V	1	-40 °C	125 ¯C	TO-220-5	Positive	Step-Down	1.81 mOhm	52 kHz	3 A	Through Hole	3.3 V
Microchip Technology LM2576-5.0BU	TO-263-5	Buck	4 V	1	-40 °C	125 ¯C	D2PAK (5 Leads + Tab) TO-263-6 TO-263BA	Positive	Step-Down	1.81 mOhm	52 kHz	3 A	Surface Mount	5 V
Microchip Technology LM2576-12WT	TO-220-5	Buck	4 V	1	-40 °C	125 ¯C	TO-220-5	Positive	Step-Down	1.81 mOhm	52 kHz	3 A	Through Hole	12 V
Microchip Technology LM2576-3.3WU	TO-263-5	Buck	4 V	1	-40 °C	125 ¯C	D2PAK (5 Leads + Tab) TO-263-6 TO-263BA	Positive	Step-Down	1.81 mOhm	52 kHz	3 A	Surface Mount	3.3 V
Microchip Technology LM2576-12BU TR	TO-263-5	Buck	4 V	1	-40 °C	125 ¯C	D2PAK (5 Leads + Tab) TO-263-6 TO-263BA	Positive	Step-Down	1.81 mOhm	52 kHz	3 A	Surface Mount	12 V
Microchip Technology LM2576WT	TO-220-5	Buck	4 V	1	-40 °C	125 ¯C	TO-220-5	Positive	Step-Down		52 kHz	3 A	Through Hole	1.23 V	Adjustable	37 V

Catalog

3A Step-Down SMPS Regulator

Key Features

• + 3.3V, 5V, 12V, and adjustable output versions

• + Voltage over specified line and load conditions:

• + Fixed version: ±3% max. output voltage

• + Adjustable version: ±2% max. feedback voltage

• + Guaranteed 3A output current

• + Wide input voltage range: 4V to 40V

• + Wide output voltage range: 1.23V to 37V

• + Requires only 4 external components

• + 52kHz fixed frequency internal oscillator

• + Low power standby mode IQ typically < 200µA

• + 80% efficiency (adjustable version typically > 80%)

• + Uses readily available standard inductors

• + Thermal shutdown and current limit protection

• + 100% electrical thermal limit burn-in

Description

The LM2576 series of monolithic integrated circuits provide all the active functions for a step-down (buck) switching regulator. Fixed versions are available with a 3.3V, 5V, or 12V fixed output. Adjustable versions have an output voltage range from 1.23V to 37V. Both versions are capable of driving a 3A load with excellent line and load regulation. These regulators are simple to use because they require a minimum number of external components and include internal frequency compensation and a fixed-frequency oscillator. The LM2576 series offers a high efficiency replacement for popular three-terminal adjustable linear regulators. It substantially reduces the size of the heat sink, and in many cases no heat sink is required. A standard series of inductors available from several different manufacturers are ideal for use with the LM2576 series. This feature greatly simplifies the design of switch-mode power supplies. The feedback voltage is guaranteed to ±2% tolerance for adjustable versions, and the output voltage is guaranteed to ±3% for fixed versions, within specified input voltages and output load conditions. The oscillator frequency is guaranteed to±10%. External shutdown is included, featuring less than 200µA standby current. The output switch includes cycle-by-cycle current limiting and thermal shutdown for full protection under fault conditions.