Features: · Fixed 3.3-V, 5-V, 12-V, and 15-V Options With ±5% Regulation (Max) Over Line, Load, and Temperature Conditions
· Adjustable Option With a Range of 1.23 V to 37 V and ±4% Regulation (Max) Over Line, Load, and Temperature Conditions
· Specified 1-A Output Current
· Wide Input Voltage Range¼4.75 V to 40 V
· Requires Only Four External Components (Fixed Versions) and Uses Readily Available Standard Inductors
· 52-kHz (Typ) Fixed-Frequency Internal Oscillator
· TTL Shutdown Capability With 50-mA (Typ) Standby Current
· High Efficiency¼as High as 88% (Typ)
· Thermal Shutdown and Current-Limit Protection With Cycle-by-Cycle CurrentLimitingApplication· Simple High-Efficiency Step-Down (Buck)Regulator
· Pre-Regulator for Linear Regulators
· On-Card Switching Regulators
· Positive-to-Negative Converter (Buck-Boost)Pinout
Specifications
|
|
MAX |
MIN |
UNIT |
|
|
Supply voltage |
42 |
|
V |
VIN |
|
ON/OFF pin input voltage |
VIN |
0.3 |
V |
|
|
Output voltage to GND (steady state) |
-1 |
|
V
|
|
|
Maximum junction temperature |
150 |
j
|
°C |
TJ |
|
Storage temperature range |
150 |
65 |
°C |
Tstg |
(1) Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute maximum-rated conditions for extended periods may affect device reliability.
DescriptionThe LM25751A greatly simplifies the design of switching power supplies by conveniently providing all the active functions needed for a step-down (buck) switching regulator in an integrated circuit. Accepting a wide input voltage range and available in fixed output voltages of 3.3 V, 5 V, 12 V, 15 V, or an adjustable output version, the LM2575 has an integrated switch capable of delivering 1 A of load current, with excellent line and load regulation. The device also offers internal frequency compensation, a fixed-frequency oscillator, cycle-by-cycle current limiting, and thermal shutdown. In addition, a manual shutdown is available via an external ON/OFF pin. The LM2575 represents a superior alternative to popular three-terminal linear regulators. Due to its high efficiency, it significantly reduces the size of the heat sink and, in many cases, no heat sink is required.
Optimized for use with standard series of inductors available from several different manufacturers, the LM2575 greatly simplifies the design of switch-mode power supplies by requiring a minimal addition of only four to six external components for operation.
The LM25751A is characterized for operation over the virtual junction temperature range of 40°C to 125°C.
LM25751A Data Sheet
