LM317: 100-mA Adjustable Voltage Regulator

LM317:  100-mA Adjustable Voltage Regulator

The LM317L-N is an adjustable positive voltage regulator capable of supplying 100 mA over a 1.2-V to 37-V output range. The LM317L-N is easy to use and requires only two external resistors to set the output voltage. Both line and load regulation are better than standard fixed regulators. The LM317L-N is available packaged in a standard, easy-to-use TO-92 transistor package.
The LM317L-N offers full overload protection. Included on the chip are current limit, thermal overload protection, and safe area protection. Normally, no capacitors are required unless the device is situated more than 6 inches from the input filter capacitors, in which case an input bypass is required.
The LM317L-N uses floating topology and sees only the input-to-output differential voltage, therefore supplies of several hundred volts can be regulated, provided the maximum input-to-output differential is not exceeded. The device makes a simple adjustable switching regulator, a programmable output regulator, or by connecting a fixed resistor between the adjustment and output, the LM317L-N can be used as a precision current regulator.
The LM317L-N is available in a standard 3-pin TO-92 transistor package, the 8-pin SOIC package, and 6- pin DSBGA package. The LM317L-N is rated for operation over a −40°C to 125°C range.

 

Features

  • Adjustable Output Down to 1.2 V
  • 100-mA Output Current
  • Capable of Handling up to 40V VIN
  • Line Regulation Typically 0.01% /V
  • Load Regulation Typically 0.1% /A
  • No Output Capacitor Required (†)
  • Current Limit Constant With Temperature
  • Eliminates the Need to Stock Many Voltages
  • Standard 3-Lead Transistor Package
  • 80-dB Ripple Rejection
  • Available in 3-Pin TO-92, 8-Pin SOIC, or 6-pin DSBGA Packages
  • Output is Short-Circuit Protected
  • See AN-1112 (SNVA009) for DSBGA Considerations

Applications

  • Automotive LED Lighting
  • Battery Chargers
  • Post Regulation for Switching Supplies
  • Constant-Current Regulators
  • Microprocessor Supplies