LM117 series

This is the general description of LM117 series:The LM117 series of adjustable 3-terminal positive voltage regulators is capable of supplying in excess of 1.5A over a 1.2V to 37V output range. They are exceptionally easy to use and require only two external resistors to set the output voltage. Further, both line and load regulation are better than standard fixed regulators. Also, the LM117 is packaged in standard transistor packages which are easily mounted and handled.

In addition to higher performance than fixed regulators, the LM117 series offers full overload protection available only in IC's. Included on the chip are current limit, thermal overload protection and safe area protection. All overload protection circuitry remains fully functional even if the adjustment terminal is disconnected. Normally, no capacitors are needed unless the device is situated more than 6 inches from the input filter capacitors in which case an input bypass is needed. An optional output capacitor can be added to improve transient response. The adjustment terminal can be bypassed to achieve very high ripple rejection ratios which are difficult to achieve with standard 3-terminal regulators.

Besides replacing fixed regulators, the LM117 series is useful in a wide variety of other applications. Since the regulator is "floating" and sees only the input-to-output differential voltage, supplies of several hundred volts can be regulated as long as the maximum input to output differential is not exceeded, i.e., avoid short-circuiting the output.

And these are the features: The first one is Guaranteed 1% output voltage tolerance (LM317A). The second one is Guaranteed max. 0.01%/V line regulation (LM317A). The third one is Guaranteed max. 0.3% load regulation (LM117 series). The forth one is Guaranteed 1.5A output current. The fifth one is Adjustable output down to 1.2V. The sixth one is Current limit constant with temperature. The seventh one is P+ Product Enhancement tested. The eighth one is 80 dB ripple rejection. The ninth one is Output is short-circuit protected.