LM117中文资料具有短路保护功能的扩展温度 1.5A 可调线性稳压器数据手册TI规格书

描述 Description

The LM117 and LM317-N series of adjustable 3-pin positive voltage regulators are capable of supplying in excess of 1.5 A over a 1.25-V to 37-V output range and a wide temperature 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.

The LM117 and LM317-N offer full overload protection such as current limit, thermal overload protection and safe area protection. All overload protection circuitry remains fully functional even if the adjustment terminal is disconnected.

Typically, 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 that are difficult to achieve with standard 3-terminal regulators.

Because the regulator is floating and detects 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. That is, avoid short-circuiting the output.

By connecting a fixed resistor between the adjustment pin and output, the LM117 and LM317-N can be also used as a precision current regulator. Supplies with electronic shutdown can be achieved by clamping the adjustment terminal to ground, which programs the output to 1.25 V where most loads draw little current.

For applications requiring greater output current, see the LM150 series (3 A) and LM138 series (5 A) data sheets. For the negative complement, see the LM137 series data sheet.

特性 Features

• For a newer drop-in alternative, see the LM317
• Typ. 0.1% load regulation
• Typ. 0.01%/V line regulation
• 1.5-A output current
• Adjustable output down to 1.25 V
• Current limit constant with temperature
• 80-dB ripple rejection
• Short-circuit protected output
• −55°C to 150°C operating temperature range (LM117)

简介

LM117属于集成电路（IC）的线性+开关稳压器。由TI制造生产的LM117稳压器 - 线性线性稳压器用于提供稳定的输出电压，无论负载电流、输入电压或环境因素如何变化，这些输出电压通常都要保持不变。它们的工作原理要求输入电压维持在高于所需的输出电压，而且要超出某个最小量，并且在工作时会将输入端的任何多余电压转换为热量。对于大多数应用而言，虽然这种稳压器的效率低于开关模式的稳压器，但它们通常更适合对噪声高度敏感的应用。