深圳市中立信电子科技有限公司

1 Features

1• 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 the HV Version), ±4% Maximum

Over Line and Load Conditions

• Available in 8-Pin Surface-Mount SOIC and 8-Pin

PDIP Packages

• Ensured 0.5-A Output Current

• Input Voltage Range up to 60 V

• Requires Only 4 External Components

• 150-kHz Fixed-Frequency Internal Oscillator

• TTL Shutdown Capability

• Low Power Standby Mode, IQ Typically 85 μA

• High Efficiency

• Uses Readily-Available Standard Inductors

• Thermal Shutdown and Current-Limit Protection

2 Applications

• Simple High-Efficiency Step-Down (Buck)

Regulator

• Efficient Preregulator for Linear Regulators

• On-Card Switching Regulators

• Positive-to-Negative Convertor
3 Description The LM2594xx 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 a 8-pin PDIP and a 8- pin surface-mount SOIC package. Requiring a minimum number of external components, these regulators are simple to use and feature internal frequency compensation, a fixedfrequency oscillator, and improved line and load regulation specifications. The LM2594xx 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 copper traces on the printedcircuit board are normally the only heat sinking needed.