LM A, Adjustable Output, Negative Voltage Regulator THREE TERMINAL ADJUSTABLE NEGATIVE VOLTAGE REGULATOR

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1 1.5 A, able Output, Negative Voltage Regulator The LM337 is an adjustable 3terminal negative 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 blowout proof. The LM337 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 LM337 can be used as a precision current regulator. Features Output Current in Excess of 1.5 A Output able between 1.2 V and 37 V Internal Thermal Overload Protection Internal Short Circuit Current Limiting Constant with Temperature Output Transistor SafeArea Compensation Floating Operation for High Voltage Applications Eliminates Stocking many Fixed Voltages Available in Surface Mount and Standard 3Lead Transistor Package PbFree Packages are Available I PROG THREETERMINAL ADJUSTABLE NEGATIVE VOLTAGE REGULATOR D2T SUFFIX CASE 936 Pin MARKING DIAGRAMS LM 337yyyy AWLYWWG Heatsink surface (shown as terminal 4 in case outline drawing) is connected to Pin 2. C in * 1. F I Adj R 2 12 C O ** 1. F TO22AB T SUFFIX CASE 221AB Heatsink surface connected to Pin 2. LM 337xx AWLYWWG - LM337-1 * C in is required if regulator is located more than 4 inches from power supply filter. * A 1. F solid tantalum or 1 F aluminum electrolytic is recommended. ** C O is necessary for stability. A 1. F solid tantalum or 1 F aluminum electrolytic ** is recommended V 1 R 2 xx yyyy A WL Y WW G = BT, T = BD2T, D2T = Assembly Location = Wafer Lot = Year = Work Week = PbFree Package Figure 1. Standard Application ORDERING INFORMATION See detailed ordering and shipping information in the package dimensions section on page 8 of this data sheet. Semiconductor Components Industries, LLC, 212 April, 212 Rev. 9 1 Publication Order Number: LM337/D

2 MAXIMUM RATINGS (T A = 25 C, unless otherwise noted) Rating Symbol Value Unit InputOutput Voltage Differential V I V O 4 Vdc Power Dissipation Case 221A T A = 25 C Thermal Resistance, JunctiontoAmbient Thermal Resistance, JunctiontoCase Case 936 () T A = 25 C Thermal Resistance, JunctiontoAmbient Thermal Resistance, JunctiontoCase P D JA JC P D JA JC Internally Limited Internally Limited 7 5. Operating Junction Temperature Range T J 4 to 125 C Storage Temperature Range T stg 65 to 15 C Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. ELECTRICAL CHARACTERISTICS ( V I V O = 5. V; I O =.5 A for T package; T J = T low to T high [Note 1]; I max and P max [Note 2].) Characteristics Figure Symbol Min Typ Max Unit Line Regulation (Note 3), T A = 25 C, 3. V V I V O 4 V 1 Reg line.1.4 %/V Load Regulation (Note 3), T A = 25 C, 1 ma I O I max V O 5. V V O 5. V load Thermal Regulation, T A = 25 C (Note 5), 1 ms Pulse Reg therm.3.4 % V O /W ment Pin Current 3 I Adj 65 1 A ment Pin Current Change, 2.5 V V I V O 4 V, 1 ma I L I max, P D P max, T A = 25 C W C/W C/W W C/W C/W mv % V O 1, 2 I Adj A Reference Voltage, T A = 25 C, 3. V V I V O 4 V, 3 V ref ma I O I max, P D P max, T J = T low to T high Line Regulation (Note 3), 3. V V I V O 4 V 1 Reg line.2.7 %/V V Load Regulation (Note 3), 1 ma I O I max V O 5. V V O 5. V load mv % V O Temperature Stability (T low T J T high ) 3 T S.6 % V O Minimum Load Current to Maintain Regulation 3 I Lmin ma ( V I V O 1 V) ( V I V O 4 V) Maximum Output Current V I V O 15 V, P D P max, T Package V I V O 4 V, P D P max,, T Package max RMS Noise, % of V O, T A = 25 C, 1 Hz f 1 khz N.3 % V O Ripple Rejection, V O = 1 V, f = 12 Hz (Note 4) 4 RR db C Adj = 1 F LongTerm Stability, T J = T high (Note 6), T A = 25 C for Endpoint Measurements S.3 1. %/1. k Hrs. Thermal Resistance, JunctiontoCase, T Package R JC 4. C/W 1. T low to T high = to 125 C, for LM337T, D2T. T low to T high = 4 to 125 C, for LM337BT, BD2T. 2. I max = 1.5 A, P max = 2 W 3. Load and line regulation are specified at constant junction temperature. Change in V O because of heating effects is covered under the Thermal Regulation specification. Pulse testing with a low duty cycle is used. 4. C Adj, when used, is connected between the adjustment pin and ground. 5. 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. 6. 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. A 2

3 Representative Schematic Diagram 1 2.5k 2.k k 1k 8 15pF 25pF 5.k k 1k 8 15pF 2.k 18k 4.k 1.k 6.k 1 9.6k 3.k 2.2k 18k 3k k 8.k 4.k 2k 1pF 5.pF 24 5.k 1k 5 2.4k pf This device contains 39 active transistors. R 2 1% C in 1. F I Adj C O 1. F * Pulse testing required. 1% Duty Cycle is suggested. LM % R L V IH V OH * V EE V IL V V OL OH Line Regulation (% V) V OH x 1 V OL Figure 1. Line Regulation and I Adj /Line Test Circuit 3

4 R 2 1% * Pulse testing required. 1% Duty Cycle is suggested. C in 1. F I Adj C O 1. F 12 -V I LM337 I L * R L (max Load) -V O (min Load) -V O (max Load) V O (min Load) - V O (max Load) Load Regulation (mv) = V O (min Load) - V O (max Load) Load Regulation (% V O ) = x 1 V O (min Load) Figure 2. Load Regulation and I Adj /Load Test Circuit R 2 1% V I C in 1. F C O 1. F R L V O I Adj V ref 12 LM337 I L V O To Calculate R 2 : R 2 = - 1 V ref This assumes I Adj is negligible. * Pulse testing required. * 1% Duty Cycle is suggested. Figure 3. Standard Test Circuit C in 1. F R 2 1% C Adj 1 F C O 1. F R L V O 12 D 1 * 1N V LM337 = V 4.3 V f = 12 Hz * D 1 Discharges C Adj if output is shorted to Ground. Figure 4. Ripple Rejection Test Circuit 4

5 I LM337 ΔVout, OUTPUT VOLTAGE CHANGE (%) = -15 V = -1 V I L =.5 A I L = 1.5 A T J, JUNCTION TEMPERATURE ( C) I out, OUTPUT CURRENT (A) , INPUT-OUTPUT VOLTAGE DIFFERENTIAL (Vdc) Figure 5. Load Regulation Figure 6. Current Limit 8 3. IAdj, ADJUSTMENT CURRENT ( μa) T J, JUNCTION TEMPERATURE ( C) Vin -, INPUT-OUTPUT VOLTAGE DIFFERENTIAL (Vdc) = -5. V V O = 1 mv I L = 1.5 A T J, JUNCTION TEMPERATURE ( C) 1. A 5 ma 2 ma 2 ma Figure 7. ment Pin Current Figure 8. Dropout Voltage 1.27 Vref, REFERENCE VOLTAGE (V) B, QUIESCENT CURRENT (ma) T J, JUNCTION TEMPERATURE ( C) , INPUT-OUTPUT VOLTAGE DIFFERENTIAL (Vdc) Figure 9. Temperature Stability Figure 1. Minimum Operating Current 5

6 RR, RIPPLE REJECTION (db) C Adj = 1 F - = 5. V 2 I L = 5 ma f = 12 Hz , OUTPUT VOLTAGE (V) Figure 11. Ripple Rejection versus Output Voltage RR, RIPPLE REJECTION (db) = -15 V = -1 V f = 12 Hz C Adj = 1 F I O, OUTPUT CURRENT (A) Figure 12. Ripple Rejection versus Output Current RR, RIPPLE REJECTION (db) C Adj =1 F = -15 V = -1 V I L = 5 ma, OUTPUT IMPEDANCE ( ) O Ω Z = -15 V = -1 V I L = 5 ma C L = 1. F C Adj = 1 F k 1 k 1 k 1. M 1 M f, FREQUENCY (Hz) Figure 13. Ripple Rejection versus Frequency k 1 k 1 k 1. M f, FREQUENCY (Hz) Figure 14. Output Impedance, INPUT out, OUTPUT VOLTAGE DEVIATION (V) Δ ΔV VOLTAGE CHANGE (V) = -1 V I L = 5 ma C L = 1. F C Adj = 1 F t, TIME ( s) Δ VOLTAGE DEVIATION (V) L, LOAD, OUTPUT I CURRENT (A) C Adj = 1 F = -15 V = -1 V I L = 5 ma C L = 1. F t, TIME ( s) Figure 15. Line Transient Response Figure 16. Load Transient Response 6

7 APPLICATIONS INFORMATION Basic Circuit Operation The LM337 is a 3terminal floating regulator. In operation, the LM337 develops and maintains a nominal 1.25 V reference (V ref ) between its output and adjustment terminals. This reference voltage is converted to a programming current (I PROG ) by (see Figure 17), and this constant current flows through R 2 from ground. The regulated output voltage is given by: V ref 1 R 2 I Adj R 2 Since the current into the adjustment terminal (I Adj ) represents an error term in the equation, the LM337 was designed to control I Adj to less than 1 A 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 LM337 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. I Adj V ref LM337 R 2 I PROG C O V ref = V Typical Figure 17. Basic Circuit Configuration - Load Regulation The LM337 is capable of providing extremely good load regulation, but a few precautions are needed to obtain maximum performance. For best performance, the programming resistor ( ) 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 R 2 can be returned near the load ground to provide remote ground sensing and improve load regulation. External Capacitors A 1. F tantalum input bypass capacitor (C in ) is recommended to reduce the sensitivity to input line impedance. The adjustment terminal may be bypassed to ground to improve ripple rejection. This capacitor (C Adj ) prevents ripple from being amplified as the output voltage is increased. A 1 F capacitor should improve ripple rejection about 15 db at 12 Hz in a 1 V application. An output capacitance (C O ) in the form of a 1. F tantalum or 1 F aluminum electrolytic capacitor is required for 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 LM337 with the recommended protection diodes for output voltages in excess of 25 V or high capacitance values (C O > 25 F, C Adj > 1 F). Diode D 1 prevents C O from discharging thru the IC during an input short circuit. Diode D 2 protects against capacitor C Adj discharging through the IC during an output short circuit. The combination of diodes D 1 and D 2 prevents C Adj from the discharging through the IC during an input short circuit. - C in R 2 CAdj LM337 - D1 1N42 Figure 18. Voltage Regulator with Protection Diodes C O D 2 1N42 R θja, THERMAL RESISTANCE JUNCTION TO AIR ( C/W) Free Air Mounted Vertically Minimum Size Pad P D(max) for T A = 5 C 2. oz. Copper L ÎÎÎÎ LÎÎÎÎ ÎÎÎÎ R JA L, LENGTH OF COPPER (mm) Figure 19. Thermal Resistance and Maximum Power Dissipation versus P.C.B. Copper Length P D, MAXIMUM POWER DISSIPATION (W) 7

8 ORDERING INFORMATION LM337BD2T LM337BD2TG Device Operating Temperature Range Package Shipping (PbFree) 5 Units / Rail LM337BD2TR4 LM337BD2TR4G T J = 4 to 125 C (PbFree) 8 / Tape & Reel LM337BT TO22AB LM337BTG LM337D2T TO22AB (PbFree) 5 Units / Rail LM337D2TG (PbFree) LM337D2TR4 LM337D2TR4G T J = to 125 C (PbFree) 8 / Tape & Reel LM337T LM337TG TO22AB TO22AB (PbFree) 5 Units / Rail For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD811/D. 8

9 PACKAGE DIMENSIONS CASE 9363 ISSUE D K B J F G R A S H SIDE VIEW DUAL GAUGE TOP VIEW 2X D.1 (.254) M CONSTRUCTION T N P DETAIL C OPTIONAL CHAMFER L M C DETAIL C T SEATING PLANE T ED V TERMINAL 4 U BOTTOM VIEW C OPTIONAL CHAMFER DETAIL C BOTTOM VIEW OPTIONAL CONSTRUCTIONS T ES SIDE VIEW SINGLE GAUGE CONSTRUCTION NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, CONTROLLING DIMENSION: INCHES. 3. TAB CONTOUR OPTIONAL WITHIN DIMENSIONS A AND K. 4. DIMENSIONS U AND V ESTABLISH A MINIMUM MOUNTING SURFACE FOR TERMINAL DIMENSIONS A AND B DO NOT INCLUDE MOLD FLASH OR GATE PROTRUSIONS. MOLD FLASH AND GATE PROTRUSIONS NOT TO EXCEED.25 (.635) MAXIMUM. 6. SINGLE GAUGE DESIGN WILL BE SHIPPED AFTER FPCN EXPIRATION IN OCTOBER 211. INCHES MILLIMETERS DIM MIN MAX MIN MAX A B C D ED ES F.51 REF REF G.1 BSC 2.54 BSC H J.125 MAX MAX K.5 REF 1.27 REF L M N P R 5 REF 5 REF S.116 REF REF U.2 MIN 5.8 MIN V.25 MIN 6.35 MIN SOLDERING FOOTPRINT* X X PITCH DIMENSIONS: MILLIMETERS *For additional information on our PbFree strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. 9

10 PACKAGE DIMENSIONS TO22, SINGLE GAUGE CASE 221AB ISSUE A B F T S C T SEATING PLANE NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, CONTROLLING DIMENSION: INCHES. 3. DIMENSION Z DEFINES A ZONE WHERE ALL BODY AND LEAD IRREGULARITIES ARE ALLOWED. 4. PRODUCT SHIPPED PRIOR TO 28 HAD DIMENSIONS S = INCHES ( MM) INCHES MILLIMETERS DIM MIN MAX MIN MAX A B C D F G H J K L N Q R S T U V Z H Q Z L V G N D A K U R J ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. Typical parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including Typicals must be validated for each customer application by customer s technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. PUBLICATION ORDERING INFORMATION LITERATURE FULFILLMENT: Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 8217 USA Phone: or Toll Free USA/Canada Fax: or Toll Free USA/Canada orderlit@onsemi.com N. American Technical Support: Toll Free USA/Canada Europe, Middle East and Africa Technical Support: Phone: Japan Customer Focus Center Phone: ON Semiconductor Website: Order Literature: For additional information, please contact your local Sales Representative LM337/D