AIC431/TL431A/TL431 Adjustable Precision Shunt Regulators n FEATURES n DESCRIPTION l Unconditionally Stable. l Precision Reference Voltage. AIC431 :2.495V ±0.5% TL431A :2.495V ±1.0% TL431 :2.495V ±1.6% l Sink Current Capability: 200mA. l Minimum Cathode Current for Regulation: 250µA. l Equivalent Full-Range Temperature Coefficient: 50 ppm/°C. l Fast Turn-On Response. l Low Dynamic Output Impedance: 0.08Ω. l Adjustable Output Voltage. l Low Output Noise. l Space Saving SOT-89, SOT-23, TO-92 and SO8 packages. n TYPICAL APPLICATION CIRCUIT V IN V OUT + R1 The AIC431/TL431A/TL431 are 3-terminal adjustable precision shunt regulators with guaranteed temperature stability over the applicable extended commercial temperature range. The output voltage may be set at any level greater than 2.495V (V REF) up to 30V merely by selecting two external resistors that act as a voltage divider network. These devices have a typical output impedance of 0.08Ω. Active output circuitry provides a very sharp turn-on characteristics, making these devices excellent improved replacements for zener diodes in many applications. The precise ±0.5% reference voltage tolerance of the AIC431 makes it possible in many applications to avoid the use of a variable resistor, consequently saving cost and eliminating drift and reliability problems associated with it. + AIC431 R2 VOUT=(1+R1/R2)VREF Precision Regulator Analog Integrations Corporation 4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC DS-431-06 May 31, 01 TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw 1 AIC431/TL431A/TL431 n ORDERING INFORMATION AIC431 CX TL431A CX TL431 CX ORDER NUMBER PACKAGING TYPE S: SMALL OUTLINE U: SOT-23 X: SOT-89 Z: TO-92 AIC431CS TL431ACS TL431CS (SO-8) AIC431CUN TL431ACUN TL431CUN (SOT-23) PIN CONFIGURATION TOP VIEW CATHOD 1 8 REF ANODE 2 7 ANODE ANODE 3 6 ANODE NC 4 5 NC 3 FRONT VIEW 1: CATHODE 2: VREF 3: ANODE 1 AIC431CUS TL431ACUS TL431CUS (SOT-23) 2 3 FRONT VIEW 1: VREF 2: CATHODE 3: ANODE 1 AIC431CX TL431ACX TL431CX (SOT-89) FRONT VIEW 1: VREF 2: ANODE 3: CATHODE 1 AIC431CZ TL431ACZ TL431CZ (TO-92) 2 FRONT VIEW 1: VREF 2: ANODE 3: CATHODE 2 3 1 2 3 n ABSOLUTE MAXIMUM RATINGS Cathode Voltage ........… … … … … ...............… … … … … ..… … … ...............................30V Continuous Cathode Current ...................… … … … .… … ...................... -10mA ~ 250mA Reference Input Current Range .......… … … … ........… … ..........… … … … … … … … 10mA Operating Temperature Range .......… … … … .........… … … .........… … … … … . -40°C ~ 85°C Lead Temperature .......… … … … ..................… … … … … … ..… … … … … … … … … . 260°C Storage Temperature .......… … … … ..................… … … … … ..… … … … … .. -65°C ~ 150°C Power Dissipation (Notes 1, 2) SOT-89 Package .........… … … … ...... 0.80W TO-92 Package … .......… … … … ....... 0.78W Note 1: TJ, max = 150°C. Note 2: Ratings apply to ambient temperature at 25°C. 2 AIC431/TL431A/TL431 n TEST CIRCUITS IN IL IN VZ IL R1 IREF VZ AIC431 IREF IZ IZ VREF R2 VREF AIC431 Note: V Z=V REF(1+R1/R2)+IREFxR1 Fig. 1 Test Circuit for VZ=VREF Fig. 2 Test circuit for VZ>VREF IN VZ AIC431 IZ(OFF) Fig. 3 Test circuit for off-state Current n ELECTRICAL CHARACTERISTICS (Ta=25°C, unless otherwise specified.) PARAMETER Reference Voltage TEST CONDITIONS VZ=VREF, AIC431 IL =10mA (Fig. 1) TL431A SYMBOL VREF TL431 Deviation of Reference Input Voltage Over Temperature (Note 3) VZ = VREF , IL =10mA, Ratio of the Change in Reference Voltage to the Change in Cathode voltage IZ=10mA ∆VZ=10V-VREF (Fig. 2) ∆VZ=30V-10V Reference Input Current R1 =10KΩ, R2=∞, IL =10mA (Fig. 2) Ta = 0°C~ +85°C (Fig. 1) VDEV ∆VREF ∆VZ IREF MIN. TYP. MAX. UNIT 2.482 2.495 2.508 2.470 2.495 2.520 2.455 2.495 2.535 9.0 20 mV -0.5 -2.0 mV/V -0.35 -1.5 mV/V 0.8 3.5 µA V 3 AIC431/TL431A/TL431 Deviation of Reference Input Current over Temperature R1 =10KΩ, R2=∞, IL =10mA Ta =-20°C ~ +85°C (Fig. 2) αIREF 0.3 1.2 µA 4 AIC431/TL431A/TL431 n ELECTRICAL CHARACTERISTICS (Continued) PARAMETER SYMBOL TEST CONDITIONS MIN. TYP. MAX. UNIT Minimum Cathode current for Regulation VZ=VREF (Fig. 1) IZ(MIN) 0.25 0.5 mA Off-State Current VZ=20V, VREF =0V (Fig. 3) IZ(OFF) 0.1 1.0 µA Dynamic Output Impedance (Note 4) VZ=VREF Frequency= 0Hz (Fig. 1) RZ 0.08 0.3 Ω Where: T2−T1=full temperature change. αVREF can be positive or negative depending on whether the slope is positive or negative. Example: VDEV= 9.0mV, VREF= 2495mV, T2−T1= 70°C, slope is negative. VMAX VDEV = V MAX-V MIN VMIN αVREF T1 9.0mV 106 2495mV = = −50ppm/ °C 70°C T2 TEMPERATURE Note 3. Deviation of reference input voltage, VDEV, is defined as the maximum variation of the reference input voltage over the full temperature range. Note 4. The dynamic output impedance, Rz, is defined as: The average temperature coefficient of the reference input voltage, αVREF is d efined as: VMAX - VMIN 6 6 VDEV ± ± 10 10 ppm VREF(at 25°C) VREF(at 25°C) ∆VREF = = °C T2 − T1 T2 − T1 When the device is programmed with two external resistors, R1 and R2, (see Fig. 2), the dynamic output impedance of the overall circuit, is defined as: n TYPICAL RZ = rz = Cathode Current vs Cathode Voltage Reference Voltage vs Temperature 2.58 VZ =V REF TA =25° C VZ =VREF 2.56 IZ(MIN) Reference Voltage (V) Cathode Current (µA) [ ] ∆Vz R1 ≅ Rz 1+ R2 ∆Iz PERFORMANCE CHARACTERISTICS 1000 800 ∆VZ ∆IZ 600 400 200 0 -200 IZ =10mA 2.54 VREF =2.535V 2.52 2.50 VREF =2.495V 2.48 2.46 2.44 VREF=2.455V -400 2.42 -600 -1.0 -0.5 0.0 0.5 1.0 1.5 Cathode Voltage (V) 2.0 2.5 3.0 2.40 -40 -20 0 20 40 60 80 100 120 Temperature (°C ) 5 AIC431/TL431A/TL431 n TYPICAL PERFORMANCE CHARACTERISTICS (Continued) Reference Input Current vs Temperature 0.28 Dynamic Impedance vs Temperature R1=10KΩ R2=∞ IZ =10mA 1.15 1.10 Dynamic Impedance (Ω) Reference Input Current (µA) 1.20 1.05 1.00 0.95 0.90 0.85 0.80 0.24 V Z=VREF IZ =1mA to100mA 0.20 F <1KHz 0.16 0.12 0.08 0.04 0.75 0.70 -40 0.00 -40 -20 0 20 40 60 80 100 -20 0 20 60 80 100 120 Temperature (° C) Temperature (° C) Off-State Cathode Current vs Temperature Change in Reference Voltage vs Cathode Voltage 0 2.5 Off-State Cathode Current (µA) Change in Reference Voltage (mV) 40 120 -1 IZ =10mA -2 TA =25°C -3 -4 -5 -6 0 5 10 15 20 25 30 35 40 2.0 VREF=0V VZ =30V 1.5 1.0 0.5 0.0 -40 -20 0 20 40 60 80 100 120 Temperature (° C) Cathode Voltage (V) Small Signal Voltage Amplification Small Signal Voltage Amplification vs Frequency 80 70 IZ =10mA 60 TA=25° C Output 50 47µF 40 R1 10K 250 Av 30 + CIN V IN 20 R AIC431 V1 10 0 -1010 100 1k 10k 100k 1M 10M Frequency (Hz) Test Circuit For Frequency Response 6 AIC431/TL431A/TL431 n TYPICAL PERFORMANCE CHARACTERISTICS (Continued) Pulse Response RB Input 220 Pulse Generator f=100kHz OUTPUT RA 50 Output AIC431 Test Circuit For Pulse Respnose Stability Boundary Conditions 100 Cathode Current (mA) VZ 80 V Z=VREF Stable R 60 150 AIC431 CL 40 VIN Stable 20 0 1E-4 1E-3 0.01 0.1 1 10 Load Capacitance (µF) The areas between the curves represent condition that may cause the device oscillate Test Circuit for Stability Boundary Conditions Dynamic impedance vs. Frequency Dynamic Impedance (Ω) 10 Iz=10mA TA=25° C R1 Output 50 1 AIC431 + AC R2 50 + 3V 0.1 GND 1K 10K 100K 1M Frequency (Hz) 7 AIC431/TL431A/TL431 n n SYMBOL BLOCK DIAGRAM CATHODE (C) REF (R) REF (R) CATHODE (C) + - AIC431 2.495V ANODE (A) ANODE (A) n APPLICATION EXAMPLES VIN VIN R1B R R1A AIC431 R2A R2B AIC431 + AIC431 ON C OFF LED on when Low Limit<VIN< High Limit Low Limit ≅ VREF (1+R1B/R2B) Delay=R x C x ln ( V V− V IN IN High Limit ≅ VREF (1+R1A/R2A) Fig. 4 Voltage Monitor ) REF Fig. 5 Delay Timer VIN R CL IOUT IOUT VIN AIC431 RS AIC431 IOUT =VREF/ RCL IOUT =VREF /RS Fig. 6 Current Limiter or Current Source Fig. 7 Constant-Current Sink 8 AIC431/TL431A/TL431 n APPLICATION EXAMPLES (Continued) VOUT VIN VIN FUSE VOUT R1 R1 AIC431 AIC431 R2 R2 VOUT ≅ (1+R1/R2) x VREF VLIMIT ≅ (1+R1/R2) x VREF Fig 8. Higher-Current Shunt Regulator Fig 9. Crow Bar VIN R1A R1B AIC431 Output ON when Low Limit <VIN < High Limit + AIC431 R2A R2B VBE Low Limit≅ VREF ( 1+ R1B/ R2B )+ VBE High Limit ≅ VREF ( 1+ R1A/ R2A ) Fig 10. Over-Voltage/Under-Voltage Protection Circuit 9 AIC431/TL431A/TL431 n PHYSICAL DIMENSIONS l 8 LEAD PLASTIC SO (unit: mm) D SYMBOL MIN MAX A 1.35 1.75 A1 0.10 0.25 B 0.33 0.51 C 0.19 0.25 D 4.80 5.00 E 3.80 4.00 H E e e A H 5.80 6.20 L 0.40 1.27 SYMBOL MIN MAX A 1.00 1.30 A1 — 0.10 A2 0.70 0.90 b 0.35 0.50 C 0.10 0.25 D 2.70 3.10 E 1.40 1.80 A1 C B l L SOT-23 (unit: mm) C D L E H θ1 e e A A2 A1 b l 1.27(TYP) 1.90 (TYP) H 2.60 3.00 L 0.37 — θ1 1° 9° SOT-23 MARKING Part No. AIC431CUN TL431CUN TL431ACUN Marking AC1N AC2N AC3N Part No. AIC431CUS TL431CUS TL431ACUS Marking AC1S AC2S AC3S 10 AIC431/TL431A/TL431 n PHYSICAL DIMENSIONS (Continued) l SOT-89 (unit: mm) D A SYMBOL MIN MAX C A 1.40 1.60 B 0.36 0.48 C 0.35 0.44 D 4.40 4.60 D1 1.62 1.83 E 2.29 2.60 D1 H E L B e e1 l 1.50 (TYP.) e1 3.00 (TYP.) H 3.94 4.25 L 0.89 1.20 SYMBOL MIN MAX A 4.32 5.33 SOT-89 MARKING Part No. AIC431CX TL431CX TL431ACX l e Marking AC01B AC02B AC03B TO-92 (unit: mm) A E L C C e1 D 0.38 (TYP.) D 4.40 5.20 E 3.17 4.20 e1 L 1.27 (TYP.) 12.7 - 11