The LM2597/LM2597HV series are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 0.5A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, and an adjustable output version, and are packaged in an 8-lead DIP and an 8-lead surface mount package. This series of switching regulators is similar to the LM2594 series, with additional supervisory and performance features added. Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation†, improved line and load specifications, fixed-frequency oscillator, Shutdown /Soft-start, error flag delay and error flag output. The LM2597/LM2597HV series operates at a switching frequency of 150 kHz thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Because of its high efficiency, the cop- per traces on the printed circuit board are normally the only heat sinking needed. A standard series of inductors (both through hole and sur- face mount types) are available from several different manu- facturers optimized for use with the LM2597/LM2597HV se- ries. This feature greatly simplifies the design of switch-
The LM2597/LM2597HV series are monolithic step‑down (buck) switching regulators that deliver up to 0.5 A with excellent line and load regulation. They are offered in fixed 3.3 V, 5 V, 12 V outputs and an adjustable version, and are packaged in 8‑lead DIP or surface‑mount formats.
Key features include a 150 kHz fixed‑frequency internal oscillator, shutdown/soft‑start control, over‑temperature shutdown, two‑stage current limiting, and a guaranteed ±4 % output voltage tolerance. The devices operate from 4.5 V up to 60 V (HV version) and achieve efficiencies up to 88 % in typical applications.
| Maximum Output Current | 0.5 A |
|---|---|
| Switching Frequency | 150 kHz |
The regulator uses a fixed 150 kHz internal oscillator.