LM317T

LM317 HIGH CURRENT ADJUSTABLE VOLTAGE REGULATOR General Description The LM317 is an adjustable 3−terminal positive voltage regulator capable of supplying in excess of 1.5 A over an output voltage range of 1.2 V to 37 V. This voltage regulator is exceptionally easy to use and requires only two external resistors to set the output voltage. Further, it employs internal current limiting, thermal shutdown and safe area compensation, making it essentially blow−out proof. The LM317 serves a wide variety of applications including local, on card regulation. This device can also be used to make a programmable output regulator, or by connecting a fixed resistor between the adjustment and output, the LM317 can be used as a precision current regulator. Features           Output Current in Excess of 1.5 A Output Adjustable between 1.2 V and 37 V Internal Thermal Overload Protection Internal Short Circuit Current Limiting Constant with Temperature Output Transistor Safe−Area Compensation Floating Operation for High Voltage Applications Eliminates Stocking many Fixed Voltages Available in Surface Mount D2PAK−3, and Standard 3−Lead Transistor Package NCV Prefix for Automotive and Other Applications Requiring Unique Site and Control Change Requirements; AEC−Q100 Qualified and PPAP Capable These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS Compliant Ordering Information DEVICE Package Type MARKING Packing Packing QTY LM317S SOT-223 LM317S Tape 3000/Reel LM317T T0-220 LM317T Tube 1000/BOX LM317MDTR TO-252-2L LM317M Tape 2500/Reel LM317CDTR TO-263-3L LM317C Tape 1000/Reel XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 1 页 共 13 页 LM317 HIGH CURRENT ADJUSTABLE VOLTAGE REGULATOR Block Diagram 2.1 Block Diagram Figure 1. Standard Application Absolute Maximum Rratings Rating Input-Output Voltage Differential Power Dissipation Case 221A TA=+25℃ Thermal Resistance, Junction-to-Ambient Thermal Resistance, Junction-to-Case Case 936 (D²PAK-3) TA=+25℃ Thermal Resistance, Junction-to-Ambient Thermal Resistance,Junction-to-Case Operating Junction Temperature Range Storage Temperature Range XBLWversion1.0 Symbol VI-VO Value -0.3 to 40 Unit Vdc PD θJA θJC Internally Limited 65 5.0 W ℃/W ℃/W PD θJA θJC TJ Tstg Internally Limited 70 5.0 -55 to+150 -65 to+150 W ℃/W ℃/W ℃ ℃ 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 2 页 共 13 页 LM317 HIGH CURRENT ADJUSTABLE VOLTAGE REGULATOR Stresses exceeding those listed in the Maximum Ratings table may damage the device. If any of these limits are exceeded, device functionality should not be assumed, damage may occur and reliability may be affected. Electrical Characteristics (VI-VO=5V, IO=0.5A for D2T and T packages;TJ=Tlow to Thigh(Note1);Imax and Pmax(Note2);unless otherwise noted.) Characteristics Line Regulation (Note3), TA=+25℃,3.0V≤VI-VO≤40V Load Regulation (Note3),TA=+25℃,10mA≤IO≤lmax Vo≤5.0V Vo≥5.0V Thermal Regulation, TA=+25℃ (Note 4), 20 ms Pulse Adjustment Pin Current Adjustment Pin Current Change,2.5V≤VI-VO≤40V, 10mA≤ IL≤Imax,PD≤Pmax Reference Voltage,3.0V≤VI-VO≤40V,10mA≤IO≤Imax,PD≤Pmax Line Regulation (Note3), 3.0V≤VI-VO≤40V Load Regulation (Note3),10 mA≤IO≤Imax VO≤5.0V VO≥5.0V Temperature Stability (Tlow≤TJ≤Thigh) Minimum Load Current to Maintain Regulation (VI-VO = 40V) Maximum Output Current VI-VO≤15V,PD≤Pmax.T Package VI-VO=40V,PD≤Pmax,TA=+25℃,T Package RMS Noise,% of VO,TA=+25℃,10Hz≤f≤10kHz Ripple Rejection, VO = 10V,f=120Hz (Note5) Without CAdj CAdj =10μF Thermal Shutdown (Note6) Long-Term Stability, TJ = Thigh (Note7), TA =+25℃ for Endpoint Measurements Thermal Resistance Junction-to-Case, T Package Figure 1 Symbol Regline 2 Regload Min - Typ 0.01 Max 0.04 Unit %/V - 5.0 0.1 25 0.5 mV % Vo - Regtherm - 0.03 0.07 % Vo/W 3 1,2 IAdj ∆IAdj - 50 0.2 100 5.0 μA μA 3 1 2 Vref Regline Regload 1.2 - 1.25 0.02 1.3 0.07 V %/V 3 3 3 TS - 20 0.3 0.7 3.5 70 1.5 10 1.5 0.15 2.2 0.4 - mV % Vo % Vo mA A - 0.003 - 65 80 180 0.3 1.0 5.0 - ILmin Imax - N 4 RR 3 S 66 - - RθJC - % Vo dB ℃ %/1.0 kHrs. ℃/W 1. Tlow to Thigh = 0° to +125℃, for LM317, D2T. Tlow to Thigh = −40° to +125℃, for LM317BT, BD2T, Tlow to Thigh = −55° to +150℃, for LM317BT, BD2T. 2. Imax = 1.5A, Pmax = 20W 3. Load and line regulation are specified at constant junction temperature. Changes in VO due to heating effects must be taken into account separately. Pulse testing with low duty cycle is used. 4. Power dissipation within an IC voltage regulator produces a temperature gradient on the die, affecting individual IC components on the die. These effects can be minimized by proper integrated circuit design and layout techniques. Thermal Regulation is the effect of these temperature gradients on the output voltage and is expressed in percentage of output change per watt of power change in a specified time. 5. CAdj, when used, is connected between the adjustment pin and ground. 6. Thermal characteristics are not subject to production test. 7. Since Long−Term Stability cannot be measured on each device before shipment, this specification is an engineering estimate of average stability from lot to lot. XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 3 页 共 13 页 LM317 HIGH CURRENT ADJUSTABLE VOLTAGE REGULATOR Application Circuit Figure 2. Representative Schematic Diagram Figure 3. Line Regulation and ∆IAdj/Line Test Circuit XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 4 页 共 13 页 LM317 HIGH CURRENT ADJUSTABLE VOLTAGE REGULATOR Figure 4. Load Regulation and ∆IAdj/Load Test Circuit Figure 5. Standard Test Circuit XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 5 页 共 13 页 LM317 HIGH CURRENT ADJUSTABLE VOLTAGE REGULATOR Figure 6. Ripple Rejection Test Circuit Characteristics Curves Figure 7. Load Regulation Figure Figure 9. Adjustment Pin Current Figure Figure 11. Temperature Stability Figure XBLWversion1.0 8. Current Limit 10. Dropout Voltage 12. Minimum Operating Current 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 6 页 共 13 页 LM317 HIGH CURRENT ADJUSTABLE VOLTAGE REGULATOR Figure 13. Ripple Rejection versus Output Voltage Figure 15. Ripple Rejection versus Frequency Figure 17. Line Transient Response XBLWversion1.0 Figure 14. Ripple Rejection versus Output Current Figure 16. Output Impedance Figure 18. Load Transient Response 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 7 页 共 13 页 LM317 Voltage Regulator-Adjustable Output,Positive 1.5A Basic Circuit Operation The LM317 is a 3−terminal floating regulator. In operation, the LM317 develops and maintains a nominal 1.25 V reference (Vref) between its output and adjustment terminals. This reference voltage is converted to a programming current (IPROG) by R1 (see Figure 17), and this constant current flows through R2 to ground. The regulated output voltage is given by: � VOUT=Vref � + �� +IAdjR2 � Since the current from the adjustment terminal (IAdj) represents an error term in the equation, the LM317 was designed to control IAdj to less than 100μA and keep it constant. To do this, all quiescent operating current is returned to the output terminal. This imposes the requirement for a minimum load current. If the load current is less than this minimum, the output voltage will rise. Since the LM317 is a floating regulator, it is only the voltage differential across the circuit which is important to performance, and operation at high voltages with respect to ground is possible. Load Regulation Figure 19. Basic Circuit Configuration The LM317 is capable of providing extremely good load regulation, but a few precautions are needed to obtain maximum performance. For best performance, the programming resistor (R1) should be connected as close to the regulator as possible to minimize line drops which effectively appear in series with the reference, thereby degrading regulation. The ground end of R2 can be returned near the load ground to provide remote ground sensing and improve load regulation. External Capacitors A 0.1μF disc or 1.0μF tantalum input bypass capacitor (Cin) is recommended to reduce the sensitivity to input line impedance. The adjustment terminal may be bypassed to ground to improve ripple rejection. This capacitor (CAdj) prevents ripple from being amplified as the output voltage is increased. A 10μF capacitor should improve ripple rejection about 15dB at 120Hz in a 10V application. Although the LM317 is stable with no output capacitance, like any feedback circuit, certain values of external capacitance can cause excessive ringing. An output capacitance (CO) in the form of a 1.0μF tantalum or 25μF aluminum electrolytic capacitor on the output swamps this effect and insures stability. Protection Diodes When external capacitors are used with any IC regulator it is sometimes necessary to add protection diodes to prevent the capacitors from discharging through low current points into the regulator. Figure 18 shows the LM317 with the recommended protection diodes for output voltages in excess of 25μV or high capacitance values (CO > 25μF, CAdj > 10μF). Diode D1 prevents CO from discharging thru the IC during an input short circuit. Diode D2 protects against capacitor CAdj discharging through the IC during an output short circuit. The combination of diodes D1 and D2 prevents CAdj from discharging through the IC during an input short circuit. XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 8 页 共 13 页 LM317 Voltage Regulator-Adjustable Output,Positive 1.5A Figure 20. Voltage Regulator with Protection Diodes Figure 21. D2PAK Thermal Resistance and Maximum Power Dissipation versus P.C.B. Copper Length Figure 22. ‘‘Laboratory’’ Power Supply with Adjustable XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 9 页 共 13 页 LM317 Voltage Regulator-Adjustable Output,Positive 1.5A Figure 23. Adjustable Current Limiter Figure Figure 25. Slow Turn−On Regulator Figure 24. 5.0 V Electronic Shutdown Regulator 26. Current Regulator Outline Drawing SOT223 XBLWversion1.0 Unit:mm 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 10 页 共 13 页 LM317 Voltage Regulator-Adjustable Output,Positive 1.5A XBLWversion1.0 TO220 Unit:mm TO252 Unit:mm 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 11 页 共 13 页 LM317 Voltage Regulator-Adjustable Output,Positive 1.5A TO263 Unit:mm Current Limit and Output Voltage XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 12 页 共 13 页 LM317 Voltage Regulator-Adjustable Output,Positive 1.5A Statement：  Shenzhen xinbole electronics co., ltd. reserves the right to change the product specifications, without notice! Before placing an order, the customer needs to confirm whether the information obtained is the latest version, and verify the integrity of the relevant information.  Any semiconductor product is liable to fail or malfunction under certain conditions, and the buyer shall be responsible for complying with safety standards in the system design and whole machine manufacturing using Shenzhen xinbole electronics co., ltd products, and take appropriate security measures to avoid the potential risk of failure may result in personal injury or property losses of the situation occurred!  Product performance is never ending, Shenzhen xinbole electronics co., ltd will be dedicated to provide customers with better performance, better quality of integrated circuit products. XBLWversion1.0 文档仅供参考，实际应用测试为准 www.xinboleic.com 技术支持热线：4009682003 第 13 页 共 13 页