The LM2574xx series of regulators are monolithic integrated circuits that provide all theactive functions for a step-down (buck) switching regulator, capable of driving a 0.5-A load withexcellent line and load regulation. These devices are available in fixed output voltages of 3.3 V,5 V, 12 V, 15 V, and an adjustable output version.
Requiring a minimum number of external components, these regulators are simple to use andinclude internal frequency compensation and a fixed-frequency oscillator.
The LM2574xx series offers a high-efficiency replacement for popular three-terminallinear regulators. Because of its high efficiency, the copper traces on the printed-circuit board(PCB) are normally the only heat sinking needed.
A standard series of inductors optimized for use with the LM2574MX-12 are available fromseveral different manufacturers. This feature greatly simplifies the design of switch-mode powersupplies.
Other features include a specified ±4% tolerance on output voltage within specified inputvoltages and output load conditions, and ±10% on the oscillator frequency. External shutdown isincluded, featuring 50-μA (typical) standby current. The output switch includes cycle-by-cyclecurrent limiting, as well as thermal shutdown for full protection under fault conditions.
Feature
- 3.3-V, 5-V, 12-V, 15-V, and Adjustable Output Versions
- Adjustable Version Output Voltage Range: 1.23 V to 37 V (57 V for HV version) ±4% Maximum Over Line and Load Conditions
- Specified 0.5-A Output Current
- Wide Input Voltage Range: 40 V, up to 60 V for HV Version
- 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
- Create a Custom Design Using the LM2574 With the WEBENCH Power Designer
