Product Folder Sample & Buy Support & Community Tools & Software Technical Documents LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 LM317L-N 3-Terminal Adjustable Regulator 1 Features 3 Description • • • • • • • • • The LM317L-N is an adjustable 3-terminal 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. 1 • • Adjustable Output Down to 1.2 V 100-mA Output Current Line Regulation Typically 0.01% V Load Regulation Typically 0.1% 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 2 Applications • • • • • Automotive LED Lighting Battery Chargers Post Regulation for Switching Supplies Constant-Current Regulators Microprocessor Supplies Schematic Diagram Full output current not available at high input-output voltages †Optional—improves transient response *Needed if device is more than 6 inches from filter capacitors In addition to higher performance than fixed regulators, the LM317L-N offers full overload protection. 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 required unless the device is situated more than 6 inches from the input filter capacitors, in which case an input bypass is required. 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 LM317L-N is useful in a wide variety of other applications. Because the regulator is floating and sees only the input-tooutput differential voltage, supplies of several hundred volts can be regulated, provided the maximum input-to-output differential is not exceeded. The LM317L-N 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. Supplies with electronic shutdown can be achieved by clamping the adjustment terminal to ground which programs the output to 1.2 V, where most loads draw little current. The LM317L-N is available in a standard 3-pin TO-92 transistor package, the 8-pin SOIC package, and 6pin DSBGA package. The LM317L-N is rated for operation over a −40°C to 125°C range. Device Information(1) PART NUMBER LM317L-N PACKAGE BODY SIZE (NOM) TO-92 (3) 4.30 mm × 4.30 mm SOIC (8) 3.91 mm × 4.90 mm DSBGA (6) 1.68 mm × 1.019 mm (1) For all available packages, see the orderable addendum at the end of the data sheet. 1 An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA. LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com Table of Contents 1 2 3 4 5 6 7 Features .................................................................. Applications ........................................................... Description ............................................................. Revision History..................................................... Pin Configuration and Functions ......................... Specifications......................................................... 1 1 1 2 3 4 6.1 6.2 6.3 6.4 6.5 6.6 4 4 4 4 5 6 Absolute Maximum Rating ....................................... ESD Ratings.............................................................. Recommended Operating Conditions....................... Thermal Information .................................................. Electrical Characteristics .......................................... Typical Characteristics .............................................. Detailed Description .............................................. 8 7.1 Overview ................................................................... 8 7.2 Functional Block Diagram ......................................... 9 7.3 Feature Description................................................. 10 7.4 Device Functional Modes........................................ 10 8 Application and Implementation ........................ 13 8.1 Application Information............................................ 13 8.2 Typical Applications ............................................... 13 9 Power Supply Recommendations...................... 26 10 Layout................................................................... 26 10.1 Layout Guidelines ................................................. 26 10.2 Layout Examples................................................... 26 10.3 Thermal Considerations ........................................ 27 11 Device and Documentation Support ................. 28 11.1 11.2 11.3 11.4 11.5 Documentation Support ........................................ Community Resources.......................................... Trademarks ........................................................... Electrostatic Discharge Caution ............................ Glossary ................................................................ 28 28 28 28 28 12 Mechanical, Packaging, and Orderable Information ........................................................... 28 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision J (March 2013) to Revision K • Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section. ................................................................................................ 1 Changes from Revision I (March 2013) to Revision J • 2 Page Page Changed layout of National Data Sheet to TI format ........................................................................................................... 26 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 5 Pin Configuration and Functions LP Plastic Package 3-Pin TO-92 Top View D Package 8-Pin SOIC Top View YPB Package 6-Pin DSBGA Bump Side Down YPB Package 6-Pin DSBGA Laser Mark Pin Functions PIN NAME TO-92 SOIC DSBGA I/O DESCRIPTION VIN 3 1 C1 I Supply input pin VOUT 2 2, 3, 6, 7 A1 O Voltage output pin ADJ 1 4 B2 I Output voltage adjustment pin. Connect to a resistor divider to set VO. NC — 5, 8 B1, A2, C2 — No connection Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 3 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com 6 Specifications 6.1 Absolute Maximum Rating (1) (2) MIN Power dissipation MAX Input-output voltage differential −40 Operating junction temperature Lead temperature (soldering, 4 seconds) −55 Storage temperature, Tstg (1) (2) UNIT Internally Limited 40 V 125 °C 260 °C 150 °C Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office/Distributors for availability and specifications. 6.2 ESD Ratings V(ESD) (1) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1) VALUE UNIT ±2000 V JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. Pins listed as ±2000 V may actually have higher performance. 6.3 Recommended Operating Conditions over operating free-air temperature range (unless otherwise noted) Operating temperature MIN MAX UNIT −40 125 °C 6.4 Thermal Information LM317L-N TO-92 THERMAL METRIC (1) SOIC DSBGA 6 PINS UNIT 3 PINS 0.4-in Leads 0.125-in Leads 8 PINS 180 160 165 290 °C/W RθJC(top) Junction-to-case (top) thermal resistance — 80.6 — — °C/W RθJB Junction-to-board thermal resistance — — — — °C/W ψJT Junction-to-top characterization parameter — 24.7 — — °C/W ψJB Junction-to-board characterization parameter — 135.8 — — °C/W RθJC(bot) Junction-to-case (bottom) thermal resistance — — — — °C/W RθJA (1) 4 Junction-to-ambient thermal resistance For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953. Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 6.5 Electrical Characteristics (1) PARAMETER TEST CONDITIONS Line regulation TJ = 25°C, 3 V ≤ (VIN − VOUT) ≤ 40 V, IL ≤ 20 mA (2) Load regulation TJ = 25°C, 5 mA ≤ IOUT ≤ IMAX Thermal regulation TJ = 25°C, 10-ms Pulse MIN (2) Adjustment pin current change Reference voltage 3 V ≤ (VIN − VOUT) ≤ 40 V (3) 5 mA ≤ IOUT ≤ 100 mA, P ≤ 625 mW Line regulation 3 V ≤ (VIN − VOUT) ≤ 40 V, IL ≤ 20 mA (2) Load regulation 5 mA ≤ IOUT ≤ 100 mA Temperature stability TMIN ≤ TJ ≤ TMAX Minimum load current Current limit RMS output noise, % of VOUT Ripple rejection ratio Long-term stability (1) (2) (3) UNIT 0.01 %/V 0.04 0.1% 0.5% Adjustment pin current 5 mA ≤ IL ≤ 100 mA 3 V ≤ (VIN − VOUT) ≤ 40 V, P ≤ 625 mW TYP MAX 1.2 (2) 0.04 0.2 %/W 50 100 μA 0.2 5 μA 1.25 1.3 V 0.02 0.07 %/V 0.3% 1.5% 0.65% (VIN − VOUT) ≤ 40 V 3.5 5 3 V ≤ (VIN − VOUT) ≤ 15 V 1.5 2.5 100 200 300 25 50 150 3 V ≤ (VIN − VOUT) ≤ 13 V (VIN − VOUT) = 40 V TJ = 25°C, 10 Hz ≤ f ≤ 10 kHz 65 66 TJ = 125°C, 1000 Hours mA 0.003% VOUT = 10 V, f = 120 Hz, CADJ = 0 CADJ = 10 μF mA dB 80 0.3% 1% Unless otherwise noted, these specifications apply: −25°C ≤ Tj ≤ 125°C for the LM317L-N; VIN − VOUT = 5 V and IOUT = 40 mA. Although power dissipation is internally limited, these specifications are applicable for power dissipations up to 625 mW. IMAX is 100 mA. Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are covered under the specification for thermal regulation. Thermal resistance of the TO-92 package is 180°C/W junction to ambient with 0.4-inch leads from a PCB and 160°C/W junction to ambient with 0.125-inch lead length to PCB. Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 5 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com 6.6 Typical Characteristics (Output capacitor = 0 μF unless otherwise noted.) 6 Figure 1. Load Regulation Figure 2. Current Limit Figure 3. Adjustment Current Figure 4. Dropout Voltage Figure 5. Reference Voltage Temperature Stability Figure 6. Minimum Operating Current Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Typical Characteristics (continued) (Output capacitor = 0 μF unless otherwise noted.) Figure 7. Ripple Rejection Figure 8. Ripple Rejection Figure 9. Output Impedance Figure 10. Line Transient Response Figure 11. Load Transient Response Figure 12. Thermal Regulation Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 7 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com 7 Detailed Description 7.1 Overview In operation, the LM317L-N develops a nominal 1.25-V reference voltage, VREF, between the output and adjustment terminal. The reference voltage is impressed across program resistor R1 and, because the voltage is constant, a constant current I1 then flows through the output set resistor R2, giving an output voltage of: (1) Because the 100-μA current from the adjustment terminal represents an error term, the LM317L-N was designed to minimize IADJ and make it very constant with line and load changes. To do this, all quiescent operating current is returned to the output establishing a minimum load current requirement. If there is insufficient load on the output, the output will rise. Figure 13. Typical Application Circuit for Adjustable Regulator 8 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 7.2 Functional Block Diagram Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 9 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com 7.3 Feature Description 7.3.1 Load Regulation The LM317L-N is capable of providing extremely good load regulation but a few precautions are needed to obtain maximum performance. The current set resistor connected between the adjustment terminal and the output terminal (usually 240 Ω) must be tied directly to the output of the regulator rather than near the load. This eliminates line drops from appearing effectively in series with the reference and degrading regulation. For example, a 15-V regulator with 0.05-Ω resistance between the regulator and load will have a load regulation due to line resistance of 0.05 Ω × IL. If the set resistor is connected near the load the effective line resistance will be 0.05 Ω (1 + R2/R1) or in this case, 11.5 times worse. Figure 14 shows the effect of resistance between the regulator and 240-Ω set resistor. With the TO-92 package, it is easy to minimize the resistance from the case to the set resistor, by using two separate leads to the output pin. The ground of R2 can be returned near the ground of the load to provide remote ground-sensing and improve load regulation. Figure 14. Regulator With Line Resistance in Output Lead 7.4 Device Functional Modes 7.4.1 External Capacitors An input bypass capacitor is recommended in case the regulator is more than 6 inches away from the usual large filter capacitor. A 0.1-μF disc or 1-μF solid tantalum on the input is suitable input bypassing for almost all applications. The device is more sensitive to the absence of input bypassing when adjustment or output capacitors are used, but the above values will eliminate the possibility of problems. The adjustment terminal can be bypassed to ground on the LM317L-N to improve ripple rejection and noise. This bypass capacitor prevents ripple and noise from being amplified as the output voltage is increased. With a 10-μF bypass capacitor 80-dB ripple rejection is obtainable at any output level. Increases over 10-μF do not appreciably improve the ripple rejection at frequencies above 120 Hz. If the bypass capacitor is used, it is sometimes necessary to include protection diodes to prevent the capacitor from discharging through internal low current paths and damaging the device. In general, the best type of capacitors to use is solid tantalum. Solid tantalum capacitors have low impedance even at high frequencies. Depending upon capacitor construction, it takes about 25 μF in aluminum electrolytic to equal 1-μF solid tantalum at high frequencies. Ceramic capacitors are also good at high frequencies; but some types have a large decrease in capacitance at frequencies around 0.5 MHz. For this reason, a 0.01-μF disc may seem to work better than a 0.1-μF disc as a bypass. Although the LM317L-N is stable with no output capacitors, like any feedback circuit, certain values of external capacitance can cause excessive ringing. This occurs with values between 500 pF and 5000 pF. A 1-μF solid tantalum (or 25-μF aluminum electrolytic) on the output swamps this effect and insures stability. 7.4.2 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. Most 10-μF capacitors have low enough internal series resistance to deliver 20-A spikes when shorted. Although the surge is short, there is enough energy to damage parts of the IC. 10 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Device Functional Modes (continued) When an output capacitor is connected to a regulator and the input is shorted, the output capacitor will discharge into the output of the regulator. The discharge current depends on the value of the capacitor, the output voltage of the regulator, and the rate of decrease of VIN. In the LM317L-N, this discharge path is through a large junction that is able to sustain a 2-A surge with no problem. This is not true of other types of positive regulators. For output capacitors of 25 μF or less, the ballast resistors and output structure of the LM317L-N limit the peak current to a low enough level so that there is no need to use a protection diode. The bypass capacitor on the adjustment terminal can discharge through a low current junction. Discharge occurs when either the input or output is shorted. Internal to the LM317L-N is a 50-Ω resistor which limits the peak discharge current. No protection is needed for output voltages of 25 V or less and 10-μF capacitance. Figure 15 shows an LM317L-N with protection diodes included for use with outputs greater than 25 V and high values of output capacitance. D1 protects against C1 D2 protects against C2 Figure 15. Regulator With Protection Diodes 7.4.3 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. Most 10-μF capacitors have low enough internal series resistance to deliver 20-A spikes when shorted. Although the surge is short, there is enough energy to damage parts of the IC. When an output capacitor is connected to a regulator and the input is shorted, the output capacitor will discharge into the output of the regulator. The discharge current depends on the value of the capacitor, the output voltage of the regulator, and the rate of decrease of VIN. In the LM317L-N, this discharge path is through a large junction that is able to sustain 15-A surge with no problem. This is not true of other types of positive regulators. For output capacitors of 25 μF or less, there is no need to use diodes. The bypass capacitor on the adjustment terminal can discharge through a low current junction. Discharge occurs when either the input, or the output, is shorted. Internal to the LM317L-N is a 50-Ω resistor which limits the peak discharge current. No protection is needed for output voltages of 25 V or less and 10-μF capacitance. Figure 16 shows an LM317L-N with protection diodes included for use with outputs greater than 25 V and high values of output capacitance. Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 11 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com Device Functional Modes (continued) æ R2 ö VOUT = 1.25 V ç 1 + + I ADJ (R2 ) R1 ÷ø è D1 protects against C1 D2 protects against C2 Figure 16. Regulator With Protection Diodes 7.4.4 DSBGA Light Sensitivity Exposing the LM317L-N DSBGA package to bright sunlight may cause the VREF to drop. In a normal office environment of fluorescent lighting the output is not affected. The LM317 DSBGA does not sustain permanent damage from light exposure. Removing the light source causes VREF of the LM317L-N to recover to the proper value. 12 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 8 Application and Implementation NOTE Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality. 8.1 Application Information The LM317L-N is a versatile, high-performance, linear regulator with 1% output-voltage accuracy. An output capacitor can be added to further improve transient response, and the ADJ pin can be bypassed to achieve very high ripple-rejection ratios. Its functionality can be used in many different applications that require high performance regulation, such as battery chargers, constant-current regulators, and microprocessor supplies. 8.2 Typical Applications 8.2.1 1.25-V to 25-V Adjustable Regulator Full output current not available at high input-output voltages †Optional—improves transient response *Needed if device is more than 6 inches from filter capacitors Figure 17. 1.25-V to 25-V Adjustable Regulator 8.2.1.1 Design Requirements The device component count is very minimal, employing two resistors as part of a voltage-divider circuit and an output capacitor for load regulation. An input capacitor is needed if the device is more than 6 inches from filter capacitors. An optional bypass capacitor across R2 can also be used to improve PSRR. 8.2.1.2 Detailed Design Procedure The output voltage is set based on the selection of the two resistors, R1 and R2, as shown in Figure 17. For details on capacitor selection, see External Capacitors. Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 13 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com Typical Applications (continued) 8.2.1.3 Application Curve As shown in Figure 18, VOUT rises with VIN minus some dropout voltage. This dropout voltage during start-up will vary with ROUT. VOUT = 5 V Figure 18. VOUT vs VIN 8.2.2 Digitally-Selected Outputs Figure 19 demonstrates a digitally-selectable output voltage. In its default state, all transistors are off and the output voltage is set based on R1 and R2. By driving certain transistors, the associated resistor is connected in parallel to R2, modifying the output voltage of the regulator. *Sets maximum VOUT Figure 19. Digitally-Selected Outputs 14 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Typical Applications (continued) 8.2.3 High Gain Amplifier This application uses the LM395 Power Transistor to amplify the input voltage. The LM317L connected to R2 produces a constant current of 1.2V/R2 through the BJT. By altering the base current entering the LM395, the effective resistance can be changed resulting in an appropriate voltage fluctuation at the output. Figure 20. High Gain Amplifier 8.2.4 Adjustable Current Limiter This application will limit the output current to the IOUT in the diagram. The current limit is determined by adjusting the resistance between the VOUT and VADJ pins. The 1.2-V reference voltage across R1 generates the maximum current. 12 ≤ R1 ≤ 240 Figure 21. Adjustable Current Limiter 8.2.5 Precision Current Limiter This application will limit the output current to the IOUT in the diagram. An initial reference current is generated based on the resistance between the VOUT and VADJ pins. In the case of Figure 22, 1.25 V across 1 kΩ plus half of the 500-Ω resistor results in 1 mA of current, producing 1.5 V total across the two resistors in series. This voltage also appears across R1, making the maximum current the sum of the branch currents. Figure 22. Precision Current Limiter Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 15 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com Typical Applications (continued) 8.2.6 Slow Turnon 15-V Regulator An application of LM317L-N includes a PNP transistor with a capacitor to implement slow turnon functionality (see Figure 23). As VIN rises, the PNP sinks current from the ADJ rail. The output voltage at start-up is the addition of the 1.25-V reference plus the drop across the base to emitter. While this is happening, the capacitor begins to charge and eventually opens the PNP. At this point, the device functions normally, regulating the output at 15 V. A diode is placed between C1 and VOUT to provide a path for the capacitor to discharge. Such controlled turnon is useful for limiting the in-rush current. Figure 23. Slow Turnon 15-V Regulator 8.2.7 Adjustable Regulator With Improved Ripple Rejection To improve ripple rejection, a capacitor is used to bypass the ADJ pin to GND (see Figure 24). This is used to smooth output ripple by cleaning the feedback path and stopping unnecessary noise from being fed back into the device, propagating the noise. †Solid tantalum *Discharges C1 if output is shorted to ground Figure 24. Adjustable Regulator With Improved Ripple Rejection 8.2.8 High Stability 10-V Regulator This application will regulate to an output voltage of 10 V and will remain stable even with input voltage transients. The LM329 is a precision Zener reference diode that helps maintain stability. Figure 25. High Stability 10-V Regulator 16 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Typical Applications (continued) 8.2.9 Adjustable Regulator With Current Limiter This application regulates to an output voltage set by the ratio of R2 and R1 and limits the output current using R3 as shown in Figure 26. Short circuit current is approximately 600 mV/R3, or 60 mA (compared to LM317L-NZ's 200-mA current limit). At 25-mA output only 3/4 V of drop occurs in R3 and R4. Figure 26. Adjustable Regulator With Current Limiter 8.2.10 0-V to 30-V Regulator This application regulates the output voltage from 0 V to 30 V using the resistor divider at the output. The adjustment pin reference voltage is 1.25 V so select the resistor divider that provides the needed output voltage. Full output current not available at high input-output voltages Figure 27. 0-V to 30-V Regulator Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 17 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com Typical Applications (continued) 8.2.11 Regulator With 15-mA Short-Circuit Current This application regulates to a 10-V output with a 15-mA short-circuit current. The output voltage is set by the resistor divider at the output and the PNP is required to set the short-circuit current. Figure 28. Regulator With 15-mA Short-Circuit Current 8.2.12 Power Follower This application provides an output voltage that follows the input voltage while providing a current gain. The LM395 is a power transistor that operates as an emitter follower and provides a short-circuit current limit while the LM317 acts as a constant-current load. Figure 29. Power Follower 18 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Typical Applications (continued) 8.2.13 Adjusting Multiple On-Card Regulators With Single Control Figure 30 shows how multiple LM317L-N regulators can be controlled by setting one resistor. Because each device maintains the reference voltage of about 1.25 V between its VOUT and ADJ pins, we can connect each ADJ rail to a single resistor, setting the same output voltage across all devices. This allows for independent outputs, each responding to its corresponding input only. Designers must also consider that by the nature of the circuit, changes to R1 and R2 will affect all regulators. *All outputs within ± 100 mV †Minimum load −5 mA Figure 30. Adjusting Multiple On-Card Regulators With Single Control* 8.2.14 100-mA Current Regulator This application regulates the output current to maximum of 100 mA as shown in Figure 31. Figure 31. 100-mA Current Regulator 8.2.15 1.2-V to 12-V Regulator With Minimum Program Current This application regulates the output voltage between 1.2 V and 12 V depending on the resistor divider at the output while allowing minimum programmable load current down to 2 mA as shown in Figure 32. *Minimum load current ≈ 2 mA Figure 32. 1.2-V to 12-V Regulator With Minimum Program Current Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 19 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com Typical Applications (continued) 8.2.16 50-mA Constant Current Battery Charger for Nickel-Cadmium Batteries This application provides a 50-mA constant current at the output which can be used as a constant current battery charger for Nickel-Cadmium batteries. The resistor at the output sets the output current value. Figure 33. 50-mA Constant Current Battery Charger for Nickel-Cadmium Batteries 8.2.17 5-V Logic Regulator With Electronic Shutdown Figure 34 shows a variation of the 5-V output regulator application uses the LM317L-N, along with an NPN transistor, to provide shutdown control. The NPN will either block or sink the current from the ADJ pin by responding to the TTL pin logic. When TTL is pulled high, the NPN is on and pulls the ADJ pin to GND, and the LM317L-N outputs about 1.25 V. When TTL is pulled low, the NPN is off and the regulator outputs according to the programmed adjustable voltage. *Minimum output ≈ 1.2 V Figure 34. 5-V Logic Regulator With Electronic Shutdown* 8.2.18 Current-Limited 6-V Charger The current in a battery charger application is limited by switching between constant-current and constant-voltage states (see Figure 35). When the battery pulls low current, the drop across the 1-Ω resistor is not substantial and the NPN remains off. A constant voltage is seen across the battery, as regulated by the resistor divider. When current through the battery rises past peak current, the 1 Ω provides enough voltage to turn the transistor on, pulling ADJ close to ground. This results in limiting the maximum current to the battery. *Sets peak current, IPEAK = 0.6 V/R1 **1000 μF is recommended to filter out any input transients. Figure 35. Current Limited 6-V Charger 20 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Typical Applications (continued) 8.2.19 Short Circuit-Protected 80-V Supply This application provides a 80-V output voltage from 0 mA to 20 mA as shown in Figure 36. The Triad provides an AC to DC conversion and the short-circuit protection is provided by the fuse. The output voltage can be adjusted by adjusting the resistor divider at the output. Figure 36. Short Circuit-Protected 80-V Supply Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 21 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com Typical Applications (continued) 8.2.20 Basic High-Voltage Regulator This application regulates the output voltage from 1.2 V to 160 V at 25 mA as shown in Figure 37. The output voltage is set by the resistor divider at the output. The Darlington pair transistor configuration provides a current gain from the input source to the LM317. Q1, Q2: NSD134 or similar C1, C2: 1 μF, 200-V mylar** *Heat sink Figure 37. Basic High-Voltage Regulator 22 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Typical Applications (continued) 8.2.21 Precision High-Voltage Regulator This application regulates the output voltage from 8 V to 160 V at 25 mA as shown in Figure 38. The Zener diode connected from the adjust pin to VOUT provides better precision than the basic high-voltage regulator. Q1, Q2: NSD134 or similar C1, C2: 1 μF, 200-V mylar** *Heat sink **Mylar is a registered trademark of DuPont Co. Figure 38. Precision High-Voltage Regulator 8.2.22 Tracking Regulator This application regulates to an output voltage set by the output resistor divider and also uses the LM301A operational amplifier to provide a negative voltage that tracks the output voltage. A1 = LM301A, LM307, or LF13741 only R1, R2 = matched resistors with good TC tracking Figure 39. Tracking Regulator Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 23 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com Typical Applications (continued) 8.2.23 Regulator With Trimmable Output Voltage This application provides an output voltage set by the output resistor divider that can be finely tuned to ±1% by removing output resistors. See the trim procedure in Figure 40. Trim Procedure: — If VOUT is 23.08 V or higher, cut out R3 (if lower, don't cut it out). — Then if VOUT is 22.47 V or higher, cut out R4 (if lower, don't). — Then if VOUT is 22.16 V or higher, cut out R5 (if lower, don't). This will trim the output to well within ±1% of 22.00 VDC, without any of the expense or uncertainty of a trim pot (see LB-46). This technique can be used at any output voltage level. Figure 40. Regulator With Trimmable Output Voltage 8.2.24 Precision Reference With Short-Circuit Proof Output This application provides a precise output voltage with short-circuit protection. The precision results from using the LM308A operational amplifier connected between the adjust pin and output voltage pin as a comparator with the LM299AH precision reference. *R1–R4 from thin-film network, Beckman 694-3-R2K-D or similar Figure 41. Precision Reference With Short-Circuit Proof Output 24 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Typical Applications (continued) 8.2.25 Fully-Protected (Bulletproof) Lamp Driver This application drives a lamp using a programmable gain instrumentation amplifier at the output. Figure 42. Fully-Protected (Bulletproof) Lamp Driver 8.2.26 Lamp Flasher This application uses a combination of capacitors and resistors connected between the output voltage pin and the adjust pin to cause the lamp connected at the output voltage pin to flash. Output rate—4 flashes per second at 10% duty cycle Figure 43. Lamp Flasher Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 25 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com 9 Power Supply Recommendations The input supply to the LM317L-N must be kept at a voltage level lower than the maximum input-to-output differential voltage of 40 V. When possible, the minimum dropout voltage must also be met with extra headroom to keep the LM317L-N in regulation. TI recommends using an input capacitor, especially when the input pin is located more than 6 inches away from the power supply source. For more information regarding capacitor selection, see External Capacitors. 10 Layout 10.1 Layout Guidelines Some layout guidelines should be followed to ensure proper regulation of the output voltage with minimum noise. Traces carrying the load current must be wide to reduce the amount of parasitic trace inductance and the feedback loop from VOUT to ADJ should be kept as short as possible. To improve PSRR, a bypass capacitor can be placed at the ADJ pin and must be located as close as possible to the IC. In cases when VIN shorts to ground, an external diode should be placed from VOUT to VIN to divert the surge current from the output capacitor and protect the IC. Similarly, in cases when a large bypass capacitor is placed at the ADJ pin and VOUT shorts to ground, an external diode should be placed from ADJ to VOUT to provide a path for the bypass capacitor to discharge. These diodes must be placed close to the corresponding IC pins to increase their effectiveness. 10.2 Layout Examples Figure 44. Layout Example (SOT-223) 26 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N LM317L-N www.ti.com SNVS775K – MARCH 2000 – REVISED APRIL 2016 Layout Examples (continued) Figure 45. Layout Example (TO-220) 10.3 Thermal Considerations When power is dissipated in an IC, a temperature gradient occurs across the IC chip affecting the individual IC circuit components. With an IC regulator, this gradient can be especially severe since power dissipation is large. Thermal regulation is the effect of these temperature gradients on output voltage (in percentage output change) per watt of power change in a specified time. Thermal regulation error is independent of electrical regulation or temperature coefficient, and occurs within 5 ms to 50 ms after a change in power dissipation. Thermal regulation depends on IC layout as well as electrical design. The thermal regulation of a voltage regulator is defined as the percentage change of VOUT, per watt, within the first 10 ms after a step of power is applied. The LM317L-N specification is 0.2%/W, maximum. In Figure 12, a typical output of the LM317L-N changes only 7 mV (or 0.07% of VOUT = −10 V) when a 1-W pulse is applied for 10 ms. This performance is thus well inside the specification limit of 0.2%/W × 1 W = 0.2% maximum. When the 1-W pulse is ended, the thermal regulation again shows a 7-mV change as the gradients across the LM317L-N chip die out. NOTE The load regulation error of about 14 mV (0.14%) is additional to the thermal regulation error. Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N 27 LM317L-N SNVS775K – MARCH 2000 – REVISED APRIL 2016 www.ti.com 11 Device and Documentation Support 11.1 Documentation Support 11.1.1 Related Documentation For related documentation, see the following: AN-1112 DSBGA Wafer Level Chip Scale Package (SNVA009) 11.2 Community Resources The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of Use. TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help solve problems with fellow engineers. Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and contact information for technical support. 11.3 Trademarks E2E is a trademark of Texas Instruments. All other trademarks are the property of their respective owners. 11.4 Electrostatic Discharge Caution These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. 11.5 Glossary SLYZ022 — TI Glossary. This glossary lists and explains terms, acronyms, and definitions. 12 Mechanical, Packaging, and Orderable Information The following pages include mechanical, packaging, and orderable information. This information is the most current data available for the designated devices. This data is subject to change without notice and revision of this document. For browser-based versions of this data sheet, refer to the left-hand navigation. 28 Submit Documentation Feedback Copyright © 2000–2016, Texas Instruments Incorporated Product Folder Links: LM317L-N PACKAGE OPTION ADDENDUM www.ti.com 7-Aug-2015 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan Lead/Ball Finish MSL Peak Temp (2) (6) (3) Op Temp (°C) Device Marking (4/5) LM317LITP/NOPB ACTIVE DSBGA YPB 6 250 Green (RoHS & no Sb/Br) SNAGCU Level-1-260C-UNLIM -40 to 125 P 1 LM317LITPX/NOPB ACTIVE DSBGA YPB 6 3000 Green (RoHS & no Sb/Br) SNAGCU Level-1-260C-UNLIM -40 to 125 P 1 LM317LM/NOPB ACTIVE SOIC D 8 95 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM317 LM LM317LMX NRND SOIC D 8 2500 TBD Call TI Call TI -40 to 125 LM317 LM LM317LMX/NOPB ACTIVE SOIC D 8 2500 Green (RoHS & no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LM317 LM LM317LZ/LFT1 ACTIVE TO-92 LP 3 2000 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type LM317 LZ LM317LZ/LFT2 ACTIVE TO-92 LP 3 2000 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type LM317 LZ LM317LZ/LFT3 ACTIVE TO-92 LP 3 2000 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type LM317 LZ LM317LZ/LFT4 ACTIVE TO-92 LP 3 2000 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type LM317 LZ LM317LZ/LFT7 ACTIVE TO-92 LP 3 2000 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type LM317 LZ LM317LZ/NOPB ACTIVE TO-92 LP 3 1800 Green (RoHS & no Sb/Br) CU SN N / A for Pkg Type -40 to 125 LM317 LZ (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Addendum-Page 1 Samples PACKAGE OPTION ADDENDUM www.ti.com 7-Aug-2015 Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish value exceeds the maximum column width. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. 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Addendum-Page 2 PACKAGE MATERIALS INFORMATION www.ti.com 7-Aug-2015 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) LM317LITP/NOPB DSBGA YPB 6 250 178.0 LM317LITPX/NOPB DSBGA YPB 6 3000 LM317LMX SOIC D 8 2500 LM317LMX/NOPB SOIC D 8 2500 B0 (mm) K0 (mm) P1 (mm) 8.4 1.09 1.75 0.66 4.0 178.0 8.4 1.09 1.75 0.66 330.0 12.4 6.5 5.4 2.0 330.0 12.4 6.5 5.4 2.0 Pack Materials-Page 1 W Pin1 (mm) Quadrant 8.0 Q1 4.0 8.0 Q1 8.0 12.0 Q1 8.0 12.0 Q1 PACKAGE MATERIALS INFORMATION www.ti.com 7-Aug-2015 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM317LITP/NOPB DSBGA YPB 6 250 210.0 185.0 35.0 LM317LITPX/NOPB DSBGA YPB 6 3000 210.0 185.0 35.0 LM317LMX SOIC D 8 2500 367.0 367.0 35.0 LM317LMX/NOPB SOIC D 8 2500 367.0 367.0 35.0 Pack Materials-Page 2 MECHANICAL DATA YPB0006 D 0.5±0.045 E TPA06XXX (Rev B) D: Max = 1.68 mm, Min = 1.619 mm E: Max = 1.019 mm, Min =0.958 mm 4215099/A NOTES: A. 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