TL431/TL432 - Diodes Incorporated

1 TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Description Pin Assignments The tl431 and tl432 are three terminal adjustable shunt tl431 . regulators offering excellent temperature stability and output (Top View). current handling capability up to 100mA. The output voltage may be set to any chosen voltage between and 36 volts CATHODE 1. by selection of two external divider resistors. 3 ANODE. The devices can be used as a replacement for zener Diodes in many applications requiring an improvement in zener REF 2. performance. Diodes ' tl431 has the same electrical specifications as the industry standard 431 and is available SOT23. in 2 grades with initial tolerances of 1% and for the (Top View). A and B grades respectively. NC 5 ANODE. Features Leave floating or 2. Temperature range -40 to +125 C connect to pin 5.

2 Reference Voltage Tolerance at 25 C CATHODE 3 4 REF. TL431A: SOT25. TL431B: Low Output Noise (Top View). Typical Output Impedance Sink Current Capability: 1mA to 100mA CATHODE 1 8 REF. adjustable Output Voltage: VREF to 36V ANODE 2 7 ANODE. All devices are: ANODE 3 6 ANODE. Totally Lead-Free & Fully RoHS compliant NC 4 5 NC. (Notes 1 & 2). SO-8. Halogen and Antimony Free. Green Device (Note 3) SO-8 is a future product tl432 . Applications (Top View). Opto-Coupler Linearisers Shunt Regulators REF 1. Improved Zener Variable Reference 3 ANODE. CATHODE 2. SOT23. Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See for more information about Diodes Incorporated 's definitions of Halogen and Antimony free, "Green" and Lead-Free. 3. Halogen and Antimony free "Green products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and <1000ppm antimony compounds.

3 tl431 *SO-8 is a future package 1 of 14 April 2012. Document number: DS35044 Rev. 6 - 2 Diodes Incorporated TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Absolute Maximum Ratings (Note 4). Symbol Parameter Rating Unit VKA Cathode Voltage 40 V. IKA Continuous Cathode Current 150 mA. IREF Reference Input Current to +10 mA.. TJ Operating Junction Temperature +150 C.. TST Storage Temperature -55 to +150 C. SOT23 330. PD Power Dissipation (Notes 5, 6) SOT25 500 mW. SO-8* 700. Notes: 4. Operation above the absolute maximum rating may cause device failure. Operation at the absolute maximum ratings, for extended periods, may reduce device reliability. Unless otherwise stated voltages specified are relative to the ANODE pin. 5. TJ, MAX =150 C. 6. Ratings apply to ambient temperature at 25 C. Recommended Operating Conditions Symbol Parameter Min Max Unit VKA Cathode Voltage VREF 36 V.

4 IKA Cathode Current 1 100 mA. TA Operating Ambient Temperature -40 +125 C. tl431 *SO-8 is a future package 2 of 14 April 2012. Document number: DS35044 Rev. 6 - 2 Diodes Incorporated TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Electrical Characteristics (TA = +25 C, unless otherwise noted). Symbol Parameter Test Conditions Min Typ. Max Unit VKA = VREF, TL431A VREF Reference voltage V. IKA = 10mA TL431B o TA = 0 to 70 C 6 16. Deviation of reference voltage over VKA = VREF, o VDEV TA = -40 to +85 C 14 34 mV. full temperature range (Note 5) IKA = 10mA o TA = -40 to +125 C 14 34. VREF Ratio of the change in reference VKA = 10V to VREF VKA voltage to the change in cathode IKA = 10mA mV/V. voltage VKA = 36V to 10V -1 -2. IREF Reference input current IKA = 10mA, R1 = 10K , R2 = 1 4 A. o IKA = 10mA, TA = 0 to 70 C IREF deviation over full temperature o IREF R1 = 10K , TA = -40 to +85 C A.

5 Range (Note 7). R2 = TA = -40 to +125oC Minimum cathode current for IKA(MIN) VKA = VREF mA. regulation IKA(OFF) Off-state current VKA = 36V, VREF = 0V A. |ZKA| Dynamic output impedance (Note 8) VKA = VREF, f = 0Hz . SOT23 380. Thermal Resistance Junction to o JA SOT25 250 C/W. Ambient SO-8* 70. Notes: 7. Deviation of VDEV, and IREF are defined as the maximum variation of the values over the full temperature range. The average temperature coefficient of the reference input voltage VREF is defined as: Vmax VDEV. X 106. VREF @ 25 C. VREF = ppm/ C. T2 T1. Vmin Where: T2 T1 = full temperature change. VREF can be positive or negative depending on whether the slope is VDEV = Vmax - Vmin positive or negative. Notes: 8. The dynamic output impedance, RZ, is defined as: VKA T1 T2. ZKA = Temperature IKA. When the device is programmed with two external resistors R1 and R2, the dynamic output impedance of the overall circuit, is defined as: V R1.

6 Z' = ZKA 1+. I R2. tl431 *SO-8 is a future package 3 of 14 April 2012. Document number: DS35044 Rev. 6 - 2 Diodes Incorporated TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Test Circuits Figure 1. Test circuit for VKA = VREF. Figure 2. Test circuit for VKA > VREF. Figure 3. Test circuit for IOFF. tl431 *SO-8 is a future package 4 of 14 April 2012. Document number: DS35044 Rev. 6 - 2 Diodes Incorporated TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Typical Performance Characteristics 2600 IKA = 10mA. 2580 V KA = VREF R1 = 10K . R2 = . TA = 25 C IKA = 10mA. 2560. V REF Reference Voltage (mV). IREF Reference Current ( A). 2540. 2520. 2500 2480. 2460. 2440. 2420. 2400 0. -55 -35 -15 5 25 45 65 85 105 125 -55 -35 -15 5 25 45 65 85 105 125. TA Free Air Temperature ( C) TA Free Air Temperature ( C).

7 Reference Voltage vs. Free Air Temperature Reference Current vs. Free Air Temperature 150 200. V KA = VREF. V KA = VREF. TA = 25 C. TA = 25 C. 100. IKA Cathode Current ( A). IKA Cathode Current (mA). 100. 50 IKMIN. 0. 0. -50. -100 -100. -2 -1 0 1 2 3 -2 -1 0 1 2 3. V KA Cathode Voltage (V) V KA Cathode Voltage Cathode Current vs. Cathode Voltage Cathode Current vs. Cathode Voltage V KA = 36V V KA = 3V to 36V. V REF = 0. IKOFF Off-State Cathode Current ( A). dV REF/dV KA (mV/V). -50 -25 0 25 50 75 100 125. -75 -50 -25 0 25 50 75 100 125 TA Free Air Temperature (C). TA Free Air Temperature ( C) Ratio of Delta Reference Voltage to Delta Cathode Off-State Cathode Current vs. Free Air Temperature Voltage vs. Free Air Temperature tl431 *SO-8 is a future package 5 of 14 April 2012. Document number: DS35044 Rev.

8 6 - 2 Diodes Incorporated TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Typical Performance Characteristics (cont.). 400 15. IKA = 10mA. V N = Equivalent Input Noise Voltage nV/ Hz IKA = 10mA. 380 V KA = VREF. V KA = VREF. Vn - Equivalent Input Noise Voltage - V. TA = 25 C. 10 TA = 25 C. 360. 340. 5. 320. 300 0. 280. -5. 260. 240. -10. 220. 200 -15. 10 100 1K 10K 100K 0 1 2 3 4 5 6 7 8 9 10. f- Frequency (Hz) Time (Seconds). Equivalent Input Noise Voltage vs. Frequency Equivalent Input Noise Voltage Over A 10-S Period Figure 4. Test circuit for noise input voltage tl431 *SO-8 is a future package 6 of 14 April 2012. Document number: DS35044 Rev. 6 - 2 Diodes Incorporated TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Typical Performance Characteristics (cont.). 70. IKA = 10mA. A V Small-Signal Voltage Amplification (dB).

9 TA = 25 C. 60. 50. 40. 30. 20. 10. 0. 100 1K 10K 100K 1M 10M Test circuit for voltage amplification f Frequency (Hz). Small-Signal Voltage Amplification vs. Frequency IKA = 10mA. TA = 25 C. ZKA Reference Impedance ( ). Test circuit for reference impedance 1K 10K 100K 1M 10M. f Frequency (Hz). Reference Impedance vs. Frequency tl431 *SO-8 is a future package 7 of 14 April 2012. Document number: DS35044 Rev. 6 - 2 Diodes Incorporated TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Typical Performance Characteristics (cont.). 6. TA = 25 C. Input 5. Input and Output Voltage (V). 4. 3 Out put 2. 1. Test Circuit for Pulse Response 0. 0 1 2 3 4 5 6 7 8 9 10. t Time ( s). Pulse Response 100. D TA = 25 C. D. 90. 80. C C B. IKA - Cathode Current - mA. A. 70. Stable Stable Stable 60. 50 B. Test Circuit for Curve A.

10 40. 30. A VKA = V REF. 20. B V KA = 5V. C V KA = 10V. 10 D V KA = 15V. 0. 1 10. C L -Load Capacitance - uF. Stability Boundary Conditions Test circuit for curves B, C, D. Test Circuit for Curves B, C, D. The device is stable under all conditions with a load capacitance not exceeding 50pF. The device is stable under all conditions with a load capacitance between 5nF and 20nF. The device is stable under all conditions with a load capacitance exceeding 300nF. With a cathode current not exceeding 5mA, the device is stable with any load capacitance. tl431 *SO-8 is a future package 8 of 14 April 2012. Document number: DS35044 Rev. 6 - 2 Diodes Incorporated TL431/TL432 . adjustable PRECISION SHUNT REGULATOR. Applications Information tl431 *SO-8 is a future package 9 of 14 April 2012. Document number: DS35044 Rev.