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ON Semiconductor is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner. LM431SA / LM431SB / LM431SC Programmable Shunt Regulator Features Description * * * * The LM431SA / LM431SB / LM431SC are three-terminal the output adjustable regulators with thermal stability over operating temperature range. The output voltage can be set any value between VREF (approximately 2.5 V) and 36 V with two external resistors. These devices have a typical dynamic output impedance of 0.2 . Active output circuit provides a sharp turn-on characteristic, making these devices excellent replacement for zener diodes in many applications. Programmable Output Voltage to 36 V Low Dynamic Output Impedance: 0.2 (Typical) Sink Current Capability: 1.0 to 100 mA Equivalent Full-Range Temperature Coefficient of 50 ppm/C (Typical) * Temperature Compensated for Operation Over Full Rated Operating Temperature Range * Low Output Noise Voltage * Fast Turn-on Response SOT-89 SOT-23F SOT-23 3 3 1 1 1. Ref 2. Anode 3. Cathode 1 2 1. Cathode 2. Ref 3. Anode 2 M32 - 1. Ref 2. Cathode 3. Anode M3 - 1. Cathode 2. Ref 3. Anode Ordering Information Output Voltage Operating Tolerance Temperature Product Number LM431SACMFX Top Mark(1) Package 43A SOT-23F 3L 43L SOT-23 3L LM431SACM32X 43G SOT-23 3L LM431SBCMLX 43B LM431SBCMFX 43B SOT-23F 3L LM431SACM3X 2% 1% LM431SBCM3X SOT-89 3L 43M SOT-23 3L LM431SBCM32X 43H SOT-23 3L LM431SCCMLX 43C LM431SCCMFX 43C SOT-23F 3L 43N SOT-23 3L -25 to +85C 0.5% LM431SCCM3X LM431SCCM32X LM431SAIMFX 2% -40 to +85C Packing Method Tape and Reel SOT-89 3L 43J SOT-23 3L 43AI SOT-23F 3L Note: 1. SOT-23 and SOT-23F have basically four-character marking except LM431SAIMFX. (3 letters for device code + 1 letter for date code) SOT-23F date code is composed of 1 digit numeric or alphabetic week code adding bar-type year code. > Week code: Change in every two weeks > Year code (additional bar): Rotate in three year cycle Week 01~02 03~04 05~06 07~08 09~10 11~12 13~14 15~16 17~18 19~20 21~22 23~24 25~26 Code 1 2 3 4 5 6 7 8 9 A D E F Week 27~28 29~30 31~32 33~34 35~36 37~38 39~40 41~42 43~44 45~46 47~48 49~50 51~52 Code H J K L N O P R (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 S T U V Year 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Code X www.fairchildsemi.com LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator June 2015 + - Figure 1. Block Diagram Absolute Maximum Ratings Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. Values are at TA = 25C unless otherwise noted. Symbol Parameter VKA Cathode Voltage IKA Cathode current Range (Continuous) IREF Reference Input Current Range RJA Thermal Resistance Junction-Air (2,3) PD Power Dissipation (4,5) TJ Junction Temperature Value Unit 37 V -100 to +150 mA -0.05 to +10.00 mA ML Suffix Package (SOT-89) 220 MF Suffix Package (SOT-23F) 350 M32, M3 Suffix Package (SOT-23) 400 ML Suffix Package (SOT-89) 560 MF Suffix Package (SOT-23F) 350 M32, M3 Suffix Package (SOT-23) TOPR Operating Temperature Range TSTG Storage Temperature Range C/W mW 310 150 C All products except LM431SAIMFX -25 to +85 LM431SAIMFX -40 to +85 C C -65 to +150 Notes: 2. Thermal resistance test board Size: 1.6 mm x 76.2 mm x 114.3 mm (1S0P) JEDEC Standard: JESD51-3, JESD51-7. 3. Assume no ambient airflow. 4. TJMAX = 150C; ratings apply to ambient temperature at 25C. 5. Power dissipation calculation: PD = (TJ - TA) / RJA. Recommended Operating Conditions The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings. Symbol Parameter Min. Max. Unit VKA Cathode Voltage VREF 36 V IKA Cathode Current 1 100 mA (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 www.fairchildsemi.com 2 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Block Diagram Values are at TA = 25C unless otherwise noted. Symbol VREF VREF / T Parameter Conditions Reference Input Voltage VKA = VREF, IKA = 10 mA Deviation of Reference Input Voltage OverTemperature VKA = VREF, IKA = 10 mA TMIN TA TMAX LM431SA LM431SB LM431SC Min. Typ. Max. Min. Typ. Max. Min. Typ. Max. 2.450 2.500 2.550 2.470 2.495 2.520 2.482 2.495 2.508 Unit V SOT-89 SOT-23F 4.5 17.0 4.5 17.0 4.5 17.0 mV SOT-23 6.6 24 6.6 24 6.6 24 mV VKA = -1.0 -2.7 -1.0 -2.7 -1.0 -2.7 -0.5 -2.0 -0.5 -2.0 -0.5 -2.0 1.5 4.0 1.5 4.0 1.5 4.0 A SOT-89 SOT-23F 0.4 1.2 0.4 1.2 0.4 1.2 A SOT-23 0.8 2.0 0.8 2.0 0.8 2.0 A Ratio of Change in Reference Input Voltage to the Change in Cathode Voltage IKA =10 mA Reference Input Current IKA = 10 mA, R1 = 10 K, R2 = Deviation of Reference Input Current Over Full Temperature Range IKA = 10 mA, R1 = 10 K, R2 = , TA = Full Range IKA(MIN) Minimum Cathode Current for Regulation VKA = VREF 0.45 1.00 0.45 1.00 0.45 1.00 mA IKA(OFF) Off -Stage Cathode Current VKA = 36 V, VREF = 0 0.05 1.00 0.05 1.00 0.05 1.00 A Dynamic Impedance VKA = VREF, IKA = 1 to 100 mA, f 1.0 kHz 0.15 0.50 0.15 0.50 0.15 0.50 VREF / VKA IREF IREF / T ZKA 10 V-VREF mV/V VKA = 36 V-10 V Note: 6. TMIN = -25C, TMAX = +85C. (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 www.fairchildsemi.com 3 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Electrical Characteristics(6) Values are at TA = 25C unless otherwise noted. Symbol VREF VREF(dev) Parameter Conditions LM431SAI Min. Typ. Max. Unit Reference Input Voltage VKA = VREF, IKA = 10 mA 2.450 2.500 2.550 V Deviation of Reference Input Voltage OverTemperature VKA = VREF, IKA = 10 mA, TMIN TA TMAX 5 20 mV VKA = 10 V - VREF -1.0 -2.7 VKA = 36 V - 10 V -0.5 -2.0 VREF/VKA Ratio of Change in Reference Input Voltage to Change in Cathode Voltage IKA = 10 mA IREF Reference Input Current IKA = 10 mA, R1 =10 K, R2 = 1.5 4.0 A IREF(dev) Deviation of Reference Input Current Over Full Temperature Range IKA = 10 mA, R1 = 10 K, R2 = , TMIN TA TMAX 0.8 2.0 A IKA(MIN) Minimum Cathode Current for Regulation VKA = VREF 0.45 1.00 mA IKA(OFF) Off -Stage Cathode Current VKA = 36 V, VREF = 0 0.05 1.00 A ZKA Dynamic Impedance VKA = VREF, IKA = 1 to 100 mA, f 1.0 kHz 0.15 0.50 mV/V Notes: 7. TMIN = -40C, TMAX = +85C. 8. The deviation parameters VREF(dev) and IREF(dev)are defined as the differences between the maximum and minimum values obtained over the rated temperature range. The average full-range temperature coefficient of the reference input voltage, VREF, is defined as: VREF(min) V REF( dev ) 6 --------------------------------------- 10 V ( at25C ) REF V REF ppm ------------ = ----------------------------------------------------------- C TMAX - TMIN VREF(dev) VREF(max) TMAX -TMIN where TMAX -TMIN is the rated operating free-air temperature range of the device. VREF can be positive or negative, depending on whether minimum VREF or maximum VREF, respectively, occurs at the lower temperature. Example: VREF(dev) = 4.5 mV, VREF = 2500 mV at 25 C, TMAX -TMIN = 125 C for LM431SAI. V REF 6 4.5mV - ---------------------- 10 2500mV = -------------------------------------------- = 14.4ppm C 125C Because minimum VREF occurs at the lower temperature, the coefficient is positive. (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 www.fairchildsemi.com 4 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Electrical Characteristics(7, 8) (Continued) LM431S LM431S Figure 3. Test Circuit for VKA VREF Figure 2. Test Circuit for VKA = VREF LM431S Figure 4. Test Circuit for lKA(OFF) (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 www.fairchildsemi.com 5 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Test Circuits R1 V O = V ref 1 + ------- R2 R1 V O = 1 + ------- V ref R2 LM7805/MC7805 LM431S LM431S Figure 5. Shunt Regulator Figure 6. Output Control for Three- Terminal Fixed Regulator R1 V O = 1 + ------- V ref R2 LM431S Figure 7. High Current Shunt Regulator LM431S LM431S Figure 8. Current Limit or Current Source (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 Figure 9. Constant-Current Sink www.fairchildsemi.com 6 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Typical Applications 800 150 VKA = VREF VKA = VREF o TA = 25 C o I , CATHODE CURRENT (uA) (A) IKA - Cathode Current 100 50 600 IKA(MIN) 400 200 KA 0 K I , Cathode Current Current (mA) (mA) IK - Cathode TA = 25 C -50 -100 -2 -1 0 1 2 0 -200 3 -1 0 VKA, Cathode Voltage (V) 3 Figure 11. Cathode Current vs. Cathode Voltage 0.20 3.5 0.18 Iref - Reference Input Current (A) 0.16 Iref, Reference Input Current (uA) Ioff - Off-State Cathode Current (A) Ioff , Off-State Cathode Current (uA) 2 VKA - Cathode Voltage (V) Figure 10. Cathode Current vs. Cathode Voltage 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0.00 -50 1 VKA, CATHODE VOLTAGE (V) VKA - Cathode Voltage (V) 3.0 2.5 2.0 1.5 1.0 0.5 0.0 -50 -25 0 25 50 75 100 125 -25 150 0 25 50 75 100 125 oo TA -TAmbient C) , AmbientTemperature Temperature (( C) A o TAT-, Ambient Temperature Ambient Temperature ( C) (oC) A Figure 12. OFF-State Cathode Current vs. Ambient Temperature Figure 13. Reference Input Current vs. Ambient Temperature 6 60 o TA=25 C 5 40 30 20 INPUT 4 Voltage Swing (V) 50 Voltage Swing (V) Open Loop (dB) Open LoopVoltage Voltage Gain Gain (dB) o TA = 25 C IKA = 10mA 3 OUTPUT 2 10 1 0 0 -10 1k 10k 100k 1M 0 10M 8 12 16 20 Figure 15. Pulse Response Figure 14. Frequency vs. Small Signal Voltage Amplification (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 4 Time (us) Time (s) Frequency (Hz) Frequency (Hz) www.fairchildsemi.com 7 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Typical Performance Characteristics (Continued) 5 140 A VKA = Vref B VKA = 5.0 V @ IK = 10mA 4 o TA = 25 C A 100 Current (mA) Current(mA) IKIK,-CATHODE CathodeCURRENT(mA) Current (mA) 120 80 60 3 2 40 1 20 B 0 100p 1n 10n 100n 1? 0 0.0 10? CCLL,-LOAD LoadCAPACITANCE Capacitance 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Anode-Ref. Voltage (V) Anode-Ref. Voltage(V) Figure 17. Anode-Reference Diode Curve Figure 16. Stability Boundary Conditions 5 VREF , Reference Input Voltage (V) 2.51 Current (mA) Current(mA) 4 3 2 1 0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.49 2.48 2.47 2.46 -50 2.0 -25 0 25 50 75 100 125 o TA, Ambient Temperature ( C) Ref.-Cathode (V) Ref.-Cathode Voltage Voltage(V) Figure 18. Reference-Cathode Diode Curve (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 2.50 Figure 19. Reference Input Voltage vs. Ambient Temperature www.fairchildsemi.com 8 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Typical Performance Characteristics LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Physical Dimensions & & $ 0,1 ; ; % &/ 6<00 & & 0,1 0,1 ; & 0 & $ % 0,1; & 0,1 0,1 /$1'3$77(51 5(&200(1'$7,21 6($7,1*3/$1( & & 127(681/(6627+(5:,6(63(&,),(' $5()(5(1&(72-('(&729$5,$7,21$$ %$//',0(16,216$5(,10,//,0(7(56 & '2(6127&203/<-('(&67$1'$5'9$/8( '',0(16,216$5((;&/86,9(2)%8556 02/')/$6+$1'7,(%$53527586,21 (',0(16,21$1'72/(5$1&($63(5$60( < )'5$:,1*),/(1$0(0$&5(9 Figure 20. 3-LEAD, SOT-89, JEDEC TO-243, OPTION AA (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 www.fairchildsemi.com 9 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Physical Dimensions (Continued) Figure 21. 3-LEAD, SOT23F, FLAT LEAD, LOW PROFILE (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 www.fairchildsemi.com 10 LM431SA / LM431SB / LM431SC -- Programmable Shunt Regulator Physical Dimensions (Continued) 0.95 2.920.20 3 1.40 1.30+0.20 -0.15 1 2.20 2 0.60 0.37 (0.29) 0.95 0.20 1.00 A B 1.90 1.90 LAND PATTERN RECOMMENDATION SEE DETAIL A 1.20 MAX 0.10 0.00 (0.93) 0.10 C C 2.400.30 NOTES: UNLESS OTHERWISE SPECIFIED GAGE PLANE 0.23 0.08 0.25 0.20 MIN (0.55) SEATING PLANE A) REFERENCE JEDEC REGISTRATION TO-236, VARIATION AB, ISSUE H. B) ALL DIMENSIONS ARE IN MILLIMETERS. C) DIMENSIONS ARE INCLUSIVE OF BURRS, MOLD FLASH AND TIE BAR EXTRUSIONS. D) DIMENSIONING AND TOLERANCING PER ASME Y14.5M - 1994. E) DRAWING FILE NAME: MA03DREV10 SCALE: 2X Figure 22. 3-LEAD, SOT-23, JEDEC TO-236, LOW PROFILE (c) 2004 Fairchild Semiconductor Corporation LM431SA / LM431SB / LM431SC Rev. 6.11 www.fairchildsemi.com 11 TRADEMARKS The following includes registered and unregistered trademarks and service marks, owned by Fairchild Semiconductor and/or its global subsidiaries, and is not intended to be an exhaustive list of all such trademarks. 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Datasheet contains specifications on a product that is discontinued by Fairchild Semiconductor. The datasheet is for reference information only. Rev. I74 (c) Fairchild Semiconductor Corporation www.fairchildsemi.com Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Fairchild Semiconductor: LM431SACM32X LM431SACMFX LM431SACM3X