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.
● 3.3-V, 5-V, 12-V, and Adjustable Output Versions
● Adjustable Version Output Voltage Range: 1.2 V
●to 37 V (57 V for HV Version) ±4% Maximum Over
●Line and Load Conditions
● Specified 0.5-A Output Current
● Available in 8-Pin Surface-Mount and 8-Pin PDIP
●Packages
● Input Voltage Range Up to 60 V
● 150-kHz Fixed-Frequency Internal Oscillator
● Shutdown/Soft-Start
● Out of Regulation Error Flag
● Error Output Delay
● Bias Supply Pin (VBS) for Internal Circuitry
●Improves Efficiency at High Input Voltages
● Low Power Standby Mode, IQ, Typically 85 µA
● High Efficiency
● Uses Readily Available Standard Inductors
● Thermal Shutdown and Current-Limit Protection
