The LM2597xx series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 0.5-A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3 V, 5 V, 12 V, and an adjustable output version, and are packaged in an 8-pin PDIP and an 8-pin 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 LM2597xx series operates at a switching frequency of 150-kHz, thus allowing smaller-sized filter components than what would be required with lower-frequency switching regulators. Because of its high efficiency, the copper traces on the printed-circuit board are normally the only heat sinking required.
●A standard series of inductors (both through-hole and surface-mount types) are available from several different manufacturers optimized for use with the LM2597xx series. This feature greatly simplifies the design of switch-mode power supplies.
●Other features include a specified ±4% tolerance on output voltage under all conditions of input voltage and output load conditions, and ±15% on the oscillator frequency. External shutdown is included, featuring typically 85-µA standby current. Self protection features include a two stage current limit for the output switch and an overtemperature shutdown for complete protection under fault conditions.
●The LM2597HV is for use in applications requiring and input voltage up to 60 V.
