LM317中英文资料.docVIP

信息技术学院 专业外语 专 业： 电子信息工程 班 级： B1106 姓 名： 祁楚航 学 号： 0915110607 LM317 3-TERMINAL ADJUSTABLE REGULATOR Description The LM317 is an adjustable three-terminal positive-voltage regulator capable of supplying more than 1.5A over an output-voltage range of 1.2 V to 37 V. It is exceptionally easy to use and requires only two external resistors to set the output voltage. Furthermore, both line and load regulation are better than standard fixed regulators. In addition to having higher performance than fixed regulators, this device includes on-chip current limiting, thermal overload protection, and safe-operating-area protection. All overload protection remains fully functional, even if the ADJUST terminal is disconnected. The LM317 is versatile in its applications, including uses in programmable output regulation and local on-card regulation. Or, by connecting a fixed resistor between the ADJUST and OUTPUT terminals, the LM317 can function as a precision current regulator. An optional output capacitor can be added to improve transient response. The ADJUST terminal can be bypassed to achieve very high ripple-rejection ratios, which are difficult to achieve with standard three-terminal regulators. 1、Output Voltage Range Adjustable From1.2 V to 37 V 2、Output Current Greater Than 1.5 A 3、Internal Short-Circuit Current Limiting 4、Thermal Overload Protection 5、Output Safe-Area Compensation 6、Package Options Include Plastic Small-Outline Transistor SOT-223 (DCY), Flange Mounted (KTE) and Heat-Sink Mounted (KC) Packages Adjustable Voltage regulator NOTES:A.Cis not required if the regulator is closed enough to the power-supply filter. B.Cimproves transient response, but is not needed for stability. Vis calculated as V=V(1+)+(I識2) APPLICATION INFORMATION .Basic Circuit Operation The LM317 is a 3?terminal floating regulator. In operation, the LM317 develops and maintains a nominal 1.25 V reference (V) between its o