TL431

AIC431/TL431A/TL431 Adjustable Precision Shunt Regulators n FEATURES l l n DESCRIPTION The AIC431/TL431A/TL431 are 3-terminal a djustable 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. Unconditionally Stable. Precision Reference Voltage. AIC431 TL431A TL431 :2.495V ±0.5% :2.495V ±1.0% :2.495V ±1.6% l l l Sink Current Capability: 200mA. Minimum Cathode Current for Regulation: 250µA. Equivalent Full-Range Temperature Coefficient: 50 ppm/°C. Fast Turn-On Response. Low Dynamic Output Impedance: 0.08Ω . Adjustable Output Voltage. Low Output Noise. Space Saving SOT-89, SOT-23, TO-92 and SO8 packages. l l l l l n TYPICAL APPLICATION CIRCUIT V IN + AIC431 R2 R1 V OUT + 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 PACKAGING TYPE S: SMALL OUTLINE U: SOT-23 X: SOT-89 Z: TO-92 ORDER NUMBER AIC431CS TL431ACS TL431CS (SO-8) PIN CONFIGURATION TOP VIEW CATHOD ANODE ANODE NC 1 2 3 4 8 REF 7 ANODE 6 ANODE 5 NC AIC431CUN TL431ACUN TL431CUN (SOT-23) FRONT VIEW 1: CATHODE 2: VREF 3: ANODE 3 1 2 3 AIC431CUS TL431ACUS TL431CUS (SOT-23) FRONT VIEW 1: VREF 2: CATHODE 3: ANODE 1 2 AIC431CX TL431ACX TL431CX (SOT-89) FRONT VIEW 1: VREF 2: ANODE 3: CATHODE 1 2 3 AIC431CZ TL431ACZ TL431CZ (TO-92) FRONT VIEW 1: VREF 2: ANODE 3: CATHODE 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 IN IL R1 IL VZ AIC431 IZ VZ IREF IZ VREF AIC431 R2 IREF VREF 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 TEST CONDITIONS VZ=VREF, Reference Voltage IL =10mA (Fig. 1) AIC431 TL431A TL431 Deviation of Reference Input Voltage Over Temperature (Note 3) Ratio of the Change in Reference Voltage to the Change in Cathode voltage Reference Input Current VZ = VREF , IL =10mA, Ta = 0°C~ +85°C (Fig. 1) IZ=10mA (Fig. 2) ∆VZ=10V-VREF ∆VZ=30V-10V VDEV 9.0 20 mV VREF SYMBOL MIN. 2.482 2.470 2.455 TYP. 2.495 2.495 2.495 MAX. 2.508 2.520 2.535 UNIT V ∆VREF ∆V Z IREF -0.5 -0.35 0.8 -2.0 -1.5 3.5 mV/V mV/V µA R1 =10K Ω , R2= ∞, IL =10mA (Fig. 2) 3 AIC431/TL431A/TL431 Deviation of Reference Input Current over Temperature R1 =10K Ω , 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 Minimum Cathode current for Regulation Off-State Current Dynamic Output Impedance (Note 4) TEST CONDITIONS VZ=VREF (Fig. 1) VZ=20V, VREF =0V (Fig. 3) VZ=VREF Frequency= 0Hz (Fig. 1) SYMBOL MIN. TYP. 0.25 0.1 0.08 MAX. 0.5 1.0 0.3 UNIT mA µA Ω IZ(MIN) IZ(OFF) RZ VMAX VDEV = V MAX-V MIN VMIN Where: T2−T1=full temperature change. α VREF 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. αVREF = T1 TEMPERATURE T2  9.0mV  106  2495mV    70°C = −50ppm/ °C Note 3 . Deviation of reference input voltage, VDEV, is defined as the maximum variation of the reference input voltage over the full temperature range. The average temperature coefficient of the reference input voltage, α VREF 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 Note 4. The dynamic output impedance, Rz, is defined as: RZ = ∆VZ ∆IZ 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 = ∆Vz R1 ≅ Rz 1+ R2 ∆Iz [] n TYPICAL 1000 800 600 400 200 0 -200 -400 PERFORMANCE CHARACTERISTICS Reference Voltage vs Temperature 2.58 2.56 Cathode Current vs Cathode Voltage VZ =V REF TA = 25° C VZ = VREF IZ = 10mA VREF =2.535V Reference Voltage (V) IZ(MIN) Cathode Current (µA) 2.54 2.52 2.50 2.48 2.46 2.44 2.42 VREF =2.495V VREF=2.455V -20 0 20 40 60 80 100 120 -600 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 2.40 -40 Cathode Voltage (V) Temperature (°C ) 5 AIC431/TL431A/TL431 n TYPICAL 1.20 PERFORMANCE CHARACTERISTICS (Continued) 0.28 Reference Input Current vs Temperature Reference Input Current (µ A) Dynamic Impedance (Ω) 1.15 1.10 1.05 1.00 0.95 0.90 0.85 0.80 0.75 0.70 -40 Dynamic Impedance vs Temperature R1=10KΩ R2= ∞ IZ =10mA 0.24 V Z=VREF IZ =1mA to100mA F