TL431A

PROGRAMMABLE PRECISION SHUNT REGULATOR FEATURES Programmable Output Voltage to 40V Guaranteed 0.5% Reference Voltage Tolerance Low (0.2Ω Typ.) Dynamic Output Impedance Cathode Current Range(Continuous) – 100 ~ 150 mA Equivalent Full Range Temperature Coefficient of 50PPM/℃ Temperature Compensated For Operation Over Full Rate Operating Temperature Range Low Output Noise Voltage Fast Turn-on Response TO-92, SOT-89 or SOT-23 3L Package TO-92 PKG TL431/A/C 3 T O P 2 1 SOT-23 PKG 2 TOP APPLICATION Shunt Regulator Precision High-Current Series Regulator High-Current Shunt Regulator Crowbar Circuit PWM Converter With Reference Voltage Monitor Precision Current Limiter 1 3 SOT-89 PKG TOP DESCRIPSION The TL431 is a three-terminal adjustable shunt regulator with specified thermal stability over applicable temperature VREF (Approx. 2.5V) and 40V with two external resistors. This device has a typical dynamic output impedance of 0.2Ω. Active output circuitry provides a very sharp turn-on characteristic, making this device excellent replacement for zener diodes in many applications. The TL431 is characterized for operation from -40℃ to +125℃. PIN 1. Reference ORDERING INFORMATION Device TL431 TL431TA TL431SF TL431F 1 2 3 2. Anode 3. Cathode Package TO-92(Bulk) TO-92(Taping) SOT-23 3L SOT-89 3L * Refer to the page 2 for detailed ordering Information, Absolute Maximum Ratings (Operating temperature range applies unless otherwise specified) CHARACTERISTIC Cathode Voltage Cathode Current Range(Continuous) Reference Input Current Range Junction Temperature Range Operating Temperature Range Storage Temperature Range Dec. 2010 – Rev.1.5 SYMBOL VKA IK IREF TJ TOPR TSTG MIN. -100 -0.05 -40 -40 -65 MAX. 42 150 10 150 125 150 UNIT V mA mA ℃ ℃ ℃ -1- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR RECOMMENDED OPERATING CONDITIONS CHARACTERISTIC Cathode Voltage Cathode Current TL431/A/C UNIT V mA SYMBOL VKA IK MIN. VREF 0.5 MAX. 40 100 Ordering Information VREF Package Tolerance Order No. TL431C 0.5% TL431GC TL431CTA TL431GCTA TL431A TO-92 1% TL431GA TL431ATA TL431GATA TL431 2% TL431G TL431TA TL431GTA 0.5% TL431CSF TL431GCSF TL431ASF TL431GASF TL431SF TL431GSF TL431CF TL431AF TL431F Package Marking TL431-C TL431GC TL431-C TL431GC TL431-A TL431GA TL431-A TL431GA TL431 TL431G TL431 TL431G 431 431 431 431 431 431 431 431 431 Supplied As Bulk Tape Bulk Tape Bulk 2.495V Tape Reel SOT-23 1% Reel 2% 0.5% SOT-89 1% 2% Reel Reel Reel Reel Dec. 2010 – Rev.1.5 -2- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR Ordering Information (continued) TL431/A/C Dec. 2010 – Rev.1.5 -3- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR PIN CONFIGURATION Marking Side 2 TL431/A/C TOP TOP 1 123 3 1 2 3 TO-92 PKG SOT-23 PKG SOT-89 PKG PIN DESCRIPTION Pin No. 1 2 3 TO-92 / SOT-23 / SOT-89 Name Reference Anode Cathode Function Reference Voltage Ground Input Supply Voltage TL431 ELECTRICAL CHARACTERISTICS (TA=25℃, unless otherwise specified) CHARACTERISTIC SYMBOL TEST CONDITION TL431C MIN. 2.483 2.470 2.440 TYP. 2.495 2.495 2.495 8 -1.4 -1.0 1.8 0.4 MAX. 2.507 2.520 2.550 20 -2.7 -2.0 4.0 1.2 UNIT Reference Input Voltage VREF VKA =VREF, IK =10mA TL431A TL431 V Deviation of Reference Input Voltage Ratio of Change in Reference Input Voltage to the Change in Cathode Voltage Reference Input Current Deviation of Reference Input Current Minimum Cathode Current for Regulation Off-State Cathode Current Dynamic Impedance ΔVREF/ΔT VKA = VREF, IK =10mA TA =Full Range ΔVKA=10V -VREF mV ΔVREF/ΔVKA IREF ΔIREF/ΔT IK =10mA ΔVKA=36V-10V IKA=10mA, R1=10㏀, R2=∞ IK =10mA, R1=10㏀, R2=∞ TA =Full Range VKA= VREF VKA=36V, VREF=0 VKA= VREF, IK =1mA~100mA f ≤ 1kHz 0.17 0.27 mV/V uA uA IK(MIN) IK(OFF) ZKA 0.5 0.90 0.50 mA uA Ω Dec. 2010 – Rev.1.5 -4- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR TEST CIRCUITS TL431/A/C < Fig 1. Test circuit for VKA = VREF > < Fig 2. Test circuit for VKA ≥ VREF > < Fig 3. Test circuit for IKA(OFF) > Dec. 2010 – Rev.1.5 -5- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR TL431/A/C The deviation parameters ΔVREF/ΔT and ΔIREF/ΔT are defined as the differences between the maximum and minimum values obtained over the recommended temperature range. The average full-range temperature coefficient of the reference voltage, αVREF, is defined as : VI(dev) ) × 10 6 VREF at 25℃ αVREF (ppm/ ℃) = ΔTA ( Where : ΔTA is the recommended operating free-air temperature range of the device. αVREF can be positive or negative, depending on whether minimum VREF or maximum VREF, respectively, occurs at the lower temperature. Example : Maximum VREF=2496mV at 30℃, maximum VREF=2492mV at 0℃, VREF=2495mV at 25℃, ΔTA=70℃ for TL431C. αVREF 4mV ) × 10 6 2495mV = ≈ 23ppm/ ℃ 70℃ ( Because minimum VREF occurs at the lower temperature, the coefficient is positive. Calculating Dynamic Impedance The dynamic impedance is defined as : Z KA = ΔVKA ΔIKA When the device is operating with two external resistors, the total dynamic impedance of the circuit is given by: Z' = ΔV ≈ Z KA (1 + R1/R2 ) ΔI Dec. 2010 – Rev.1.5 -6- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR TYPICAL OPERATING CHARACTERISTICS Reference Voltage vs. Ambient Temperature Pulse Response TL431/A/C Cathode Current vs. Cathode Voltage Cathode Current vs. Cathode Voltage Small Signal Voltage Amplification vs. Frequency AV-Small Signal Voltage Amplification (dB) 60 50 40 IKA = 10mA TA = 25°C Output IKA 15kΩ 10µF 232Ω 30 20 10 0 1k 10k 100k 1000k 10000k 8.25kΩ < Fig 4. TEST Circuit for Voltage Amplification > Frequency, f [Hz] Dec. 2010 – Rev.1.5 -7- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR TYPICAL OPERATING CHARACTERISTICS (continued) Stability Boundary Conditions 100 90 80 TL431/A/C 150Ω R1 IKA-Cathode Current (mA) 70 60 50 40 30 20 10 0 0 1 10 100 C CL AB STABLE STABLE R2 B D A < Fig 5. TEST Circuit > A VKA = VREF, R1= 0Ω, R2 = ∞ B VKA = 5.0V, R1=10kΩ, R2 = 10kΩ C VKA = 10.0V, R1=10kΩ, R2 = 3.3kΩ D VKA = 15.0V, R1=10kΩ, R2 = 2KΩ 1000 10000 100000 CL-Load Capacitance (nF) Dec. 2010 – Rev.1.5 -8- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR APPLICATION INFORMATION 1. Shunt Regulator TL431/A/C Note A : R Should provide cathode current 1mA to the TL431 at minimum VI(BATT) 2. Precision High-Current Series Regulator Note A : R Should provide cathode current≥1mA to the TL431 at minimum VI(BATT) 3. Output Control of a Three-Terminal Fixed Regulator Dec. 2010 – Rev.1.5 -9- HTC PROGRAMMABLE PRECISION SHUNT REGULATOR 4. High-Current Shunt Regulator TL431/A/C 5. Precision 5-V 1.5A Regulator 6. Efficient 5-V Precision Regulator NOTE A : RB Should provide cathode current≥1mA to the TL431. Dec. 2010 – Rev.1.5 - 10 - HTC PROGRAMMABLE PRECISION SHUNT REGULATOR 7. PWM Converter With Reference TL431/A/C 8. Voltage Monitor NOTE A : R3 and R4 are selected to provide the desired LED intensity and cathode current ≥1mA to the TL431 at the available VI(BATT). 9. Delay Timer Dec. 2010 – Rev.1.5 - 11 - HTC PROGRAMMABLE PRECISION SHUNT REGULATOR 10. Precision Current Limiter TL431/A/C 11. Precision Constant-Current Sink Dec. 2010 – Rev.1.5 - 12 - HTC