TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES T H E I N F I N I T E P O W E R I O F P N N O VA T I O N R O D U C T I O N DESCRIPTION The TL431/TL431A/TL431B series precision adjustable three terminal shunt voltage regulators are pin-to-pin compatible with the industry standard TL431. The output voltage of this reference is programmable by using two external resistors from 2.5V to 36V. These devices offer low output D A T A S H E E T K E Y F E AT U R E S impedance for improved load regulation. The typical output impedance of these devices is 200m. These devices find application in the feedback path of switching power supplies, OVP crowbar circuits, reference for A/D, D/A, and as zener diodes with improved turn-on characteristics. NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com. PRODUCT HIGHLIGHT W INITIAL VOLTAGE REFERENCE ACCURACY OF 0.4% (TL431B) W SINK CURRENT CAPABILITY 1mA to 100mA W TYPICAL OUTPUT DYNAMIC IMPEDANCE LESS THAN 200m; TYPICAL OUTPUT IMPEDANCE OF THE TL431B LESS THAN 100m W ADJUSTABLE OUTPUT VOLTAGE FROM 2.5V TO 36V W AVAILABLE IN SURFACE-MOUNT PACKAGES W LOW OUTPUT NOISE W TYPICAL EQUIVALENT FULL RANGE TEMPERATURE COEFFICIENT OF 30ppm/C W DIRECT PIN-TO-PIN REPLACEMENT FOR INDUSTRY STANDARD TL431 AND TL1431 PRECISION PROGRAMMABLE REFERENCES VIN VOUT R1 TL431/A & TL431B VO = 1 + R1 R2 * VREF R2 PA C K A G E O R D E R I N F O R M AT I O N TA (C) 0 to 70 -40 to 85 Initial Tolerance 2% 1% 0.4% 2% 1% 0.4% SOIC DM Plastic 8-pin TL431CDM TL431ACDM TL431BCDM TL431IDM TL431AIDM TL431BIDM TO-92 LP Plastic 3-pin TL431CLP TL431ACLP TL431BCLP TL431ILP TL431AILP TL431BILP Note: All surface-mount packages are available in Tape & Reel. Append the letter "T" to part number. (i.e. TL431CDMT) TO-92 (LP) package also available in ammo-pack. Copyright (c) 1999 Rev. 1.3 9/99 LINFINITY MICROELECTRONICS INC. 11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570 1 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N A B S O L U T E M A X I M U M R AT I N G S D A T A S H E E T PACKAGE PIN OUTS (Note 1) Cathode to Anode Voltage (VKA) (Note 2) .................................................... -0.3V to 37V Reference Input Current (IREF) ................................................................... -50A to 10mA Continuous Cathode Current (IK) ......................................................... -100mA to 150mA Operating Junction Temperature Plastic (DM, LP Packages) .................................................................................... 150C Storage Temperature Range ...................................................................... -65C to 150C Lead Temperature ..................................................................................................... 300C Note 1. Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of the specified terminal. Pin numbers refer to DIL packages only. Note 2. Voltage values are with respect to the anode terminal unless otherwise noted. CATHODE N.C. ANODE N.C. 1 8 2 7 3 6 4 5 REF ANODE ANODE N.C. DM PACKAGE (Top View) 1. CATHODE 2. ANODE T H E R M A L D ATA 3. REF DM PACKAGE: THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA 165C/W LP PACKAGE: THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA LP PACKAGE (Top View) 156C/W Junction Temperature Calculation: TJ = TA + (PD x JA). The JA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow BLOCK DIAGRAM Cathode (K) Ref (R) VREF Anode (A) 2 Copyright (c) 1999 Rev. 1.3 9/99 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T ELECTRICAL CHARACTERISTICS (Note 3) (Unless otherwise specified, these specifications apply over the operating ambient temperatures for TL431C/TL431AC/TL431BC with 0C TA 70C, TL431I/TL431AI/TL431BI with -40C TA 85C.) Parameter Reference Input Voltage Reference Drift Voltage Ratio, Ref to Cathode (Note 4) Reference Input Current Symbol TL431 TL431A TL431B TL431C TL431I TL431AC TL431AI TL431BC TL431BI TL431, TL431A TL431B TL431,TL431A VREF VREF VKA IREF TL431B Minimum Operating Current Off-State Cathode Current TL431 TL431A IMIN IOFF TL431B Dynamic Impedance TL431 TL431B | ZKA | Test Conditions IK = 10mA, VKA = VREF, TA = 25C IK = 10mA, VKA = VREF, TA = 25C IK = 10mA, VKA = VREF, TA = 25C IK = 10mA, VKA = VREF IK = 10mA, VKA = VREF IK = 10mA, VKA = VREF IK = 10mA, VKA = VREF IK = 10mA, VKA = VREF IK = 10mA, VKA = VREF IK = 10mA, VKA = 2.5V to 36V IK = 10mA, VKA = 2.5V to 36V VKA = VREF, TA = 25C VKA = VREF, TA = 25C VKA = VREF, TA = Operating Range VKA = VREF to 36V VKA = VREF to 36V, TA = 25C VKA = VREF to 36V, TA = 25C VKA = VREF to 36V, TA = Operating Range VKA = 36V, VREF = 0V, TA = 25C VKA = VREF, IK = 1mA to 100mA, f 1kHz, TA = 25C VKA = VREF, IK = 1mA to 100mA, f 1kHz, TA = 25C TL431/431A/431B Units Min. Typ. Max. 2440 2495 2550 2470 2495 2520 2490 2500 2510 4 17 5 30 4 17 5 30 4 15 5 20 -1.4 -2.7 -1.1 -2 2 4 1.5 1.9 2.3 0.4 1 0.1 1 0.1 1 2 0.18 0.5 0.2 0.5 0.1 0.2 mV mV mV mV mV mV mV mV mV mV/V mV/V A A A mA A A A A Note 3. These parameters are guaranteed by design. Note 4. VREF VKA Copyright (c) 1999 Rev. 1.3 9/99 Ratio of change in reference input voltage to the change in cathode voltage. 3 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T GRAPH / CURVE INDEX FIGURE INDEX Characteristic Curves Parameter Measurement Information FIGURE # FIGURE # 1. REFERENCE INPUT VOLTAGE vs. FREE-AIR TEMPERATURE 8. TEST CIRCUIT FOR VKA = VREF 2. REFERENCE INPUT CURRENT vs. FREE-AIR TEMPERATURE 9. TEST CIRCUIT FOR VKA > VREF 3. CATHODE CURRENT vs. CATHODE VOLTAGE 10. TEST CIRCUIT FOR IOFF 4. CATHODE CURRENT vs. CATHODE VOLTAGE 5. OFF-STATE CATHODE CURRENT vs. FREE-AIR TEMPERATURE 6. RATIO OF DELTA REFERENCE VOLTAGE TO DELTA CATHODE VOLTAGE vs. FREE-AIR TEMPERATURE 7. EQUIVALENT INPUT NOISE VOLTAGE vs. FREQUENCY Typical Characteristics FIGURE # 11. EQUIVALENT INPUT NOISE VOLTAGE OVER A 10-SECOND PERIOD 12. SMALL-SIGNAL VOLTAGE AMPLIFICATION vs. FREQUENCY 13. REFERENCE IMPEDANCE vs. FREQUENCY 14. PULSE RESPONSE 15. STABILITY BOUNDARY CONDITIONS Application Information FIGURE # 16. SHUNT REGULATOR 17. SINGLE-SUPPLY COMPARATOR WITH TEMPERATURE-COMPENSATED THRESHOLD 18. HIGH CURRENT SHUNT REGULATOR 19. CROWBAR CIRCUIT 20. VOLTAGE MONITOR 21. PRECISION CONSTANT-CURRENT SINK 4 Copyright (c) 1999 Rev. 1.3 9/99 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T CHARACTERISTIC CURVES FIGURE 1. -- REFERENCE VOLTAGE vs. FREE-AIR TEMPERATURE FIGURE 2. -- REFERENCE CURRENT vs. FREE-AIR TEMPERATURE 5 VREF = VKA IK = 10mA 2.58 (IREF) Reference Input Current - (A) (VREF) Reference Input Voltage - (V) 2.60 VREF = 2550mV 2.56 TL431/A 2.54 2.52 TL431B 2.50 2.48 VREF = 2495mV TL431/A 2.46 2.44 VREF = 2440mV TL431/A 2.42 2.4 -50 -25 25 0 50 75 100 IK = 10mA R1 = IK = 10mA 4 3 TL431/A 2 TL431B 1 0 -50 125 (TA) Ambient Temperature - (C) 0 25 50 75 100 125 (TA) Ambient Temperature - (C) FIGURE 3. -- CATHODE CURRENT vs. CATHODE VOLTAGE FIGURE 4. -- CATHODE CURRENT vs. CATHODE VOLTAGE 150 800 VKA = VREF TA = 25C VKA = VREF TA = 25C 125 100 (IK) Cathode Current - (A) (IK) Cathode Current - (A) -25 75 50 25 0 TL431/A -25 TL431B -50 600 IMIN 400 200 0 -75 -100 -200 -2 -1 0 1 2 (VKA) Cathode Voltage - (V) Copyright (c) 1999 Rev. 1.3 9/99 3 -1 0 1 2 3 (VKA) Cathode Voltage - (V) 5 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T CHARACTERISTIC CURVES FIGURE 5. -- OFF-STATE CATHODE CURRENT vs. FREE-AIR TEMPERATURE FIGURE 6. -- RATIO OF DELTA REFERENCE VOLTAGE TO DELTA CATHODE VOLTAGE vs. FREE-AIR TEMPERATURE -0.85 VKA = 36V VREF = 0 TL431/A & TL431B VKA = 3V to 36V -0.95 2 VREF / VKA - (mV/V) (IOFF) Off-State Cathode Current - (A) 2.5 1.5 1 0.5 0 -50 -1.05 -1.15 -1.25 -1.35 -25 0 25 50 75 100 125 -1.45 -50 -25 0 25 50 75 100 125 (TA) Ambient Temperature - (C) (TA) Ambient Temperature - (C) FIGURE 7. -- EQUIVALENT INPUT NOISE VOLTAGE vs. FREQUENCY 260 IO = 10mA TA = 25C (VN) Noise Voltage - (nV/ Hz) 240 220 200 180 160 140 120 100 10 100 1k 10k 100k (f) Frequency - (Hz) 6 Copyright (c) 1999 Rev. 1.3 9/99 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T PA R A M E T E R M E A S U R E M E N T I N F O R M AT I O N VKA Input VKA Input IK IK R1 IREF R2 VREF VREF FIGURE 9 -- TEST CIRCUIT FOR VKA > VREF FIGURE 8 -- TEST CIRCUIT FOR VKA = VREF VKA Input IOFF FIGURE 10 -- TEST CIRCUIT FOR IOFF Copyright (c) 1999 Rev. 1.3 9/99 7 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P D R O D U C T I O N S A T A H E E T TYPICAL CHARACTERISTICS 6 f = 0.1 to 10Hz IK = 10mA TA = 25C (VN) Input Noise Voltage - (V) 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 2 0 4 6 8 10 (t) Time - (s) FIGURE 11. -- EQUIVALENT INPUT NOISE VOLTAGE OVER A 10-SECOND PERIOD 19.1V 1k 500F VCC 910 2000F VCC 1F TL431/A & TL431B (DUT) TLE2027 AV = 10V/mV 820 TLE2027 16k 16 160k 1F 0.1F VEE 2.2F 16k 33k AV = 2V/V 1M CRO 33k VEE Test Circuit for 0.1Hz to 10Hz Equivalent Input Noise Voltage 8 Copyright (c) 1999 Rev. 1.3 9/99 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T TYPICAL CHARACTERISTICS FIGURE 12. -- SMALL-SIGNAL VOLTAGE AMPLIFICATION vs. FREQUENCY 70 (AV) Voltage Amplification - (dB) Output IK = 10mA TA = 25C 60 IK 230 15k 50 9F 40 30 8.25k 20 10 GND 0 Test Circuit for Voltage Amplification -10 1k 10k 100k 1M 10M (f) Frequency - (Hz) FIGURE 13. -- REFERENCE IMPEDANCE vs. FREQUENCY (|zKA|) Reference Impedance - ( ) 100 Output IK = 1mA to 100mA TA = 25C 1k IK 10 50 1 GND Test Circuit for Reference Impedance 0.1 1k 10k 100k 1M 10M (f) Frequency - (Hz) Copyright (c) 1999 Rev. 1.3 9/99 9 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T TYPICAL CHARACTERISTICS FIGURE 14. -- PULSE RESPONSE 6 Output VIN - (V) 5 220 4 3 Pulse Generator f = 100kHz 2 50 (VKA) Output Voltage - (V) 1 0 3 GND 2 1 Test Circuit for Pulse Response 0 1 0 2 3 4 5 6 (t) Time - (s) FIGURE 15. -- STABILITY BOUNDARY CONDITIONS (IK) Cathode Current - mA 90 80 IK R1=10k 100 A B C D VKA = VREF VKA = 5V VKA = 10V VKA = 15V 150 IK = 10mA TA = 25C CL B* R2 70 60 50 VBATT Stable Stable C* A* Test Circuit for Curve A 40 30 150 D* 20 IK 10 0 0.001 CL 0.01 0.1 1 10 VBATT (CL) Load Capacitance - (F) * The areas under the curves represent conditions that may cause the device to oscillate. For curves B, C, and D, R2 and V+ were adjusted to establish the initial VKA and IK conditions with CL = 0. VBATT and CL were then adjusted to determine the ranges of stability. 10 Test Circuit for Curves B, C, and D Copyright (c) 1999 Rev. 1.3 9/99 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T A P P L I C AT I O N I N F O R M AT I O N R (see Note) VBATT VBATT VO IK R1 0.1% TL431/A & TL431B TL431/A & TL431B VREF VO VON 2V VOFF VBATT Input R2 0.1% GND VO = Note: 1 + R1 R2 * VREF R should provide 1mA cathode current to the TL431/A & TL1431 at minimum V BATT. FIGURE 16 -- SHUNT REGULATOR VBATT FIGURE 17 -- SINGLE-SUPPLY COMPARATOR WITH TEMPERATURE-COMPENSATED THRESHOLD VO VBATT VO R1 R1 TL431/A & TL431B C TL431/A & TL431B R2 VO = 1 + R1 R2 Note: * VREF FIGURE 18 -- HIGH CURRENT SHUNT REGULATOR Copyright (c) 1999 Rev. 1.3 9/99 R2 (see Note) Refer to the stability boundary conditions in Figure 15 to determine allowable values for C. FIGURE 19 -- CROWBAR CIRCUIT 11 PRODUCT DATABOOK 1996/1997 TL431/TL431A/TL431B PRECISION PROGRAMMABLE REFERENCES P R O D U C T I O N D A T A S H E E T A P P L I C AT I O N I N F O R M AT I O N R3 (see Note) 12V VBATT IO R4 (Note) R1A TL431/A & TL431B TL431/A & TL431B R2A RS 0.1% R2B 1 + High Limit = 1 + Low Limit = R1B * VREF R2B R1B * VREF R2B LED On when Low Limit < VBATT < High Limit IO = VREF RS Note: R3 and R4 are selected to provide the desired LED intensity and 1mA cathode current to the TL431/A & TL431B at the available V+. FIGURE 20 -- VOLTAGE MONITOR FIGURE 21 -- PRECISION CONTANT-CURRENT SINK PRODUCTION DATA - Information contained in this document is proprietary to LinFinity, and is current as of publication date. This document may not be modified in any way without the express written consent of LinFinity. Product processing does not necessarily include testing of all parameters. Linfinity reserves the right to change the configuration and performance of the product and to discontinue product at any time. 12 Copyright (c) 1999 Rev. 1.3 9/99