AIC431/TL431A/TL431 Adjustable Precision Shunt Regulator n FEATURES l n DESCRIPTION Precision Reference Voltage. AIC431 :2.495V 0.5% TL431A :2.495V 1.0% TL431 :2.495V 1.6% The AIC431, TL431A and TL431 are 3terminal adjustable precision shunt regulators with guaranteed temperature stability over the applicable extended commercial temperature l Sink Current Capability: 200mA. l Minimum Cathode Current for Regulation: 250A. l Equivalent Full-Range Temperature Coefficient: 50 ppm/C. 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 l Fast Turn-On Response. that act as a voltage divider network. These l Low Dynamic Output Impedance: 0.08. devices have a typical output impedance of l Adjustable Output Voltage. 0.08. Active output circuitry provides a very l Low Output Noise. sharp turn-on characteristics, making these l Space Saving Packages: SOT-89, SOT-23, TO92 and SO-8. devices excellent improved replacements for n APPLICATIONS zener diodes in many applications. The precise 0.5% reference voltage toler- l Linear Regulators. ance of the AIC431 makes it possible in l Adjustable Supplies. many applications to avoid the use of a vari- l Switching Power Supplies. able resistor, consequently saving cost and l Battery Operated Computers. eliminating drift and reliability problems asso- l Instrumentation. ciated with it. l Computer Disk Drivers. n TYPICAL APPLICATION CIRCUIT VI N V OUT + R3 R1 + C1 C2 AIC431 R2 VOUT=(1+R1/R2)VREF Precision Regulator Analog Integrations Corporation 4F, 9 Industry E. 9th Rd, Science-Based Industrial Park, Hsinchu, Taiwan TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw DS-431-07 012102 1 AIC431/TL431A/TL431 n ORDERING INFORMATION AIC431 CXXX TL431A CXXX TL431 CXXX PIN CONFIGURATION SO-8 TOP VIEW CATHODE 1 8 REF ANODE 2 7 ANODE ANODE 3 6 ANODE NC 4 5 NC PACKING TYPE TR: TAPE & REEL TB: TUBE (for SO-8) BG: BAG SOT-23 (CUN) FRONT VIEW 1: CATHODE 2: VREF 3: ANODE PACKAGE TYPE S: SMALL OUTLINE US: SOT-23 UN: SOT-23 X: SOT-89 Z: TO-92 3 1 Example: AIC431CSTR a in SO-8 Package & Taping & Reel Packing Type (CS is not available in BAG 2 SOT-23 (CUS) FRONT VIEW 1: VREF 2: CATHODE 3: ANODE packing type.) 3 1 2 SOT-89 (CX) FRONT VIEW 1: VREF 2: ANODE 3: CATHODE 1 TO-92 (CZ) 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, TA .......... ... ... ... ............ ............ ... ... ... ... . -40C ~ 85C Lead Temperature .......... ... ... ... ..................... ... ... ... ... ... ..... ... ... ... ... ... ... ... ... . 260C Storage Temperature .......... ... ... ... ..................... ... ... ... ... ..... ... ... ... ... .. -65C ~ 150C Power Dissipation (Notes 1, 2) SOT-89 Package ............ ... ... ... ...... 0.80W TO-92 Package ... .......... ... ... ... ....... 0.78W Note 1: TJ, max = 150C. Note 2: Ratings apply to ambient temperature at 25C. 2 AIC431/TL431A/TL431 n TEST CIRCUITS IN IIN IN VZ IIN R1 IREF VZ AIC431 IREF IZ IZ V REF R2 AIC431 V REF 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 IZ(OFF) AIC431 Fig. 3 Test Circuit for off-state Current n ELECTRICAL CHARACTERISTICS (T =25C, unless otherwise specified.) A PARAMETER Reference Voltage TEST CONDITIONS VZ=VREF, AIC431 IIN =10mA (Fig. 1) TL431A SYMBOL VREF TL431 Deviation of Reference Input Voltage Over Temperature (Note 3) TYP. MAX. 2.482 2.495 2.508 2.470 2.495 2.520 2.455 2.495 2.535 9.0 20 9.0 50 UNIT V VZ = VREF , IIN =10mA, TA = 0C~ +70C (Fig. 1) VDEV TA = -40C~ +85C (Fig. 1) Ratio of the Change in Reference Voltage to the Change in Cathode voltage MIN. mV IZ=10mA VZ=10V-VREF VREF -0.5 -2.0 mV/V (Fig. 2) VZ=30V-10V VZ -0.35 -1.5 mV/V 3 AIC431/TL431A/TL431 n ELECTRICAL CHARACTERISTICS (Continued) PARAMETER TEST CONDITIONS SYMBOL MIN. TYP. MAX. UNIT IREF 0.8 3.5 A Reference Input Current R1 =10K, R2=, IIN =10mA (Fig. 2) Deviation of Reference Input Current over Temperature R1 =10K, R2=, IIN =10mA TA =-40C ~ +85C (Fig. 2) IREF 0.3 1.2 A 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 A Dynamic Output Impedance (Note 4) VZ=VREF F<1KHz (Fig. 1) RZ 0.08 0.3 Where: T2-T1=full temperature change. VREF can be positive or negative depending on whether the slope is positive or negative. Example: VDEV= 9.0mV, VREF= 2495mV, T2-T1= 70C, slope is negative. VMAX VDEV = V MAX-V MIN VMIN VREF T1 TEMPERATURE 9.0mV 106 2495mV = = -50ppm/ C 70C T2 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, VREF is d efined as: VMAX - VMIN 6 6 VDEV 10 10 ppm VREF(at 25C) VREF(at 25C) 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: RZ = rz = VZ IZ [ ] V Rz 1+ R1 R2 I 4 AIC431/TL431A/TL431 n TYPICAL PERFORMANCE CHARACTERISTICS 1000 2.58 VZ =V REF TA =25C 600 400 200 0 -200 -400 IZ =10mA 2.54 VREF =2.535V 2.52 2.50 VREF =2.495V 2.48 2.46 2.44 VREF=2.455V 2.42 -600 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 2.40 -40 3.0 -20 0 20 40 60 80 100 120 Temperature (C ) Fig. 5 Reference Voltage vs. Temperature Cathode Voltage (V) Fig. 4 Cathode Current vs. Cathode Voltage 0.28 1.20 R1=10K R2= IZ =10mA 1.15 1.10 Dynamic Impedance () Reference Input Current (A) VZ =VREF 2.56 IZ(MIN) Reference Voltage (V) Cathode Current (A) 800 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 -20 0 20 40 60 80 100 120 0.00 -40 0 20 40 60 80 100 120 Temperature ( C) Fig. 7 Dynamic Impedance vs. Temperature Temperature ( C) Fig. 6 Reference Input Current vs. Temperature 2.5 0 Off-State Cathode Current (A) Change in Reference Voltage (mV) -20 -1 IZ =10mA -2 TA =25C -3 -4 -5 -6 0 5 10 15 20 25 30 35 40 Cathode Voltage (V) Fig. 8 Change in Reference Voltage vs. Cathode Voltage 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) Fig. 9 Off-State Cathode Current vs. Temperature 5 AIC431/TL431A/TL431 Small Signal Voltage Amplification (dB) n TYPICAL PERFORMANCE CHARACTERISTICS (Continued) 80 70 IZ =10mA 60 TA=25 C 47F 50 40 Output R1 10K R2 250 Av + 30 CIN AIC431 V1 VIN 20 10 0 -10 10 100 1k 10k 100k 1M 10M Frequency (Hz) Fig. 10 Small Signal Voltage Amplification vs. Frequency Fig. 11 Test Circuit For Frequency Response RB Input OUTPUT 220 Pulse Generator f=100kHz RA 50 AIC431 Output Fig. 13 Test Circuit For Pulse Response Fig. 12 Pulse Response 100 Cathode Current (mA) VZ 80 V Z=VREF R Stable 150 60 CL AIC431 40 VIN Stable 20 0 1E-4 1E-3 0.01 0.1 1 10 Load Capacitance (F) Fig. 14 Stability Boundary Conditions Fig. 15 Test Circuit for Stability Boundary The areas between the curves represent condition that may cause the device oscillate 6 AIC431/TL431A/TL431 n TYPICAL PERFORMANCE CHARACTERISTICS (Continued) R1 Dynamic Impedance () 10 Output Iz=10mA 50 TA=25 C AIC431 + 1 AC R2 - 50 + 3V GND 0.1 1K 10K 100K 1M Frequency (Hz) Fig. 17 Test Circuit for Dynamic Impedance Fig. 16 Dynamic impedance vs. Frequency n SYMBOL n BLOCK DIAGRAM CATHODE (C) REF (R) CATHODE (C) + - REF (R) AIC431 2.495V ANODE (A) ANODE (A) n PIN DESCRIPTIONS CATHODE Pin - Sinks current with a range from 250A to 200mA for normal applications. VREF Pin - Providing VREF=2.495V (typ.) for adjustable output voltage. ANODE Pin - Anode pin sources current for normal application. The current value is the same as Cathode pin. 7 AIC431/TL431A/TL431 n APPLICATION EXAMPLES VIN VIN R3 R1B R2 R4 R3 R1 R1A AIC431 R2A AIC431 + AIC431 R2B ON C OFF LED Turn on when Low Limit