Adjustable Precision Shunt Voltage Regulator LM431A LM431B Adjustable Precision Shunt Regulator General Description • LM431A and LM431B are three terminal adjustable precision shunt regulators With guaranteed thermal stability over a full operation temperature range. • The output Voltage of these ICs can be set to any value between VREF (Typical 2.50V) and the corresponding maximum cathode voltage (36V) with two external resistors. TO-92 (Bulk) • These devices feature the sharp turn-on characteristics, low temperature coefficient and low output impedance, making them ideal substitute for Zener Diode in many applications such as switching power supply, charger and other adjustable regulators. • LM431 precision reference Voltage tolerance is offered in 2 grades:1.0% for LM431A and 0.5% for LM431B TO-92 (Ammo) • Both LM431A and LM431B are available in TO-92 (Bulk), TO-92 (Ammo),SOT-89, SOT-23,SOT-23-5 and SOP-8 packages. SOT-89 .Features • • • • • • • • Programmable Precise Output Voltage:2.50V to 36V High Stability under Capacitive Load Wide Operation Temperature Range:-40°C to 125°C Low Temperature Deviation:4.5mV (Typical) Low Equivalent Full-range Temperature Coefficient :20ppm/°C (Typical) Sink Current Capacity:1mA to100mA Low Output Noise RoHS Compliance and Halogen Free SOT-23 SOT-23-5 Applications • Switching Power Supply • Charger • Voltage Adapter • Graphic Card • Precision Voltage Reference TAITRON COMPONENTS INCORPORATED www.taitroncomponents.com Tel: Fax: (800)-TAITRON (800)-824-8766 (800)-TAITFAX (800)-824-8329 (661)-257-6060 (661)-257-6415 Rev. B/LX Page 1 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Ordering Information Pin Configuration 1: REF 2: ANODE 3: CATHODE TO-92(Bulk) 1: REF 2: CATHODE 3: ANODE SOT-23 1: REF 2: ANODE 3: CATHODE TO-92(Ammo) 1: REF 2: ANODE 3: CATHODE SOT-89 1:NC 2:NC 3: CATHODE 4: REF 5: ANODE SOT-23-5 Rev. B/LX www.taitroncomponents.com Page 2 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Functional Block Diagram Marking information Outline Temperature Range VREF Tolerance LM431AZ-08-AG LM431AZ-08-BL LM431AZ-08-BG LM431BZ-08-AR LM431BZ-08-AG LM431BZ-08-BL LM431BZ-08-BG 1.0% LM431AK-08-TR70 0.5% AS431BZ-G1 AS431AZ-E1 AS431AZ-G1 LM431AK-08-RG70 E43H G43H LM431BK-08-TR70 LM431BK-08-RG70 E43G G43G 1.0% LM431AN-08-TR70 LM431AN-08-RG70 EB6 GB6 0.5% LM431BN-08-TR70 LM431BN-08-RG70 EB5 GB5 1.0% LM431AN5-08-TR70 LM431AN5-08-RG70 E6I G6I 0.5% LM431BN5-08-TR70 LM431BN5-08-RG70 E6H G6H 0.5% -40 to 125°C SOT-23 -40 to 125°C SOT-23 -5 -40 to 125°C Marking Code Packing Halogen Free T Type RoHS AS431BZ-E1 -40 to 125°C SOT-89 Part Number Halogen Free LM431AZ-08-AR 1.0% TO-92 RoHS Ammo Bulk Ammo Bulk Tape & Reel Tape & Reel Tape & Reel Rev. B/LX www.taitroncomponents.com Page 3 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Absolute Maximum Ratings (Note1) Symbol Description Cathode Voltage Continuous Cathode Current Reference Input Current Z:TO-92 K:SOT-89 Power Dissipation N:SOT-23 N5:SOT-23-5 Junction Temperature Storage Temperature Range ESD VKA IKA IREF PD TJ TSTG ESD(Human body model) Ratings Unit 40 -100 to 150 10 V mA mA 770 mW 370 150 -65 to 150 2000 °C °C V Recommend Operating Ratings (Note1) Symbol Description VKA IKA TA Cathode Voltage Continuous Cathode Current Operating Ambient Temperature Ratings Min Max 36 VREF 1.0 100 -40 125 Unit V mA °C Note1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Recommend operating ratings indicate conditions for which the devices is functional, but do not guarantee specific specification limits. For guarantee specification and test conditions, see the electrical characteristics, the guarantee specification apply only for the test conditions listed. Electrical Characteristics (TA=25°C, unless otherwise specified) Symbol VREF Description Reference Voltage 0.5% 1.0% ∆ VREF Deviation of Reference Voltage Over Full Temperature Range ∆ VREF ∆ VKA Ratio of change in Reference Voltage to the change in Cathode Voltage Min. Typ. Max. Unit Test Circuit Test Conditions 2.487 2.475 - 2.500 2.500 4.5 4.5 4.5 -1.0 2.512 2.525 8 10 16 -2.7 V V Fig.1 VKA=VREF,IKA=10mA mV Fig.1 - -0.5 -2.0 mV/ V Fig.2 0°C to 70°C -40°C to 85°C -40°C to125°C ∆ VKA=10V to VREF ∆ VKA=36V to10V VKA=VREF IKA=10mA IKA=10mA Rev. B/LX www.taitroncomponents.com Page 4 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Symbol Description Min. Typ. Max. Unit IREF Reference Current Deviation of Reference Current Over Full Temperature Range Minimum Cathode Current for Regulation Off-state Cathode Current - 0.7 4.0 uA Test Circuit Fig.2 - 0.4 1.2 uA Fig.2 - 0.4 1.0 mA Fig.1 VKA=VREF - 0.05 1.0 uA Fig.3 Dynamic Impedance - 0.15 0.5 Ω Fig.1 Thermal Resistance - - 81.9 84.9 135.9 135.9 - °C/W VKA=36V, VREF=0V VKA=VREF, IKA=1mA to 100mA,f≤1.0KHz TO-92 SOT-89 SOT-23 SOT-23-5 ∆ IREF IKA(Min) IKA(Off) ZKA RθJC Test Conditions IKA=10mA,R1=10KΩ,R2=∞ IKA=10mA, R1=10KΩ,R2=∞ TA =-40°C to 125°C Parameter Test Circuit LM431 Fig.1 Test Circuit for VKA=VREF LM431 Fig.2 Test Circuit for VKA>VREF LM431 Fig.3 Test Circuit for IKA(Off) Rev. B/LX www.taitroncomponents.com Page 5 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Typical Characteristics Curves Fig.4 VREF-TA Fig.5 IREF-TA R1=10K Ω Reference Current IREF (uA) Reference Voltage VREF (V) VKA=VREF IKA=10mA Ambient Temperature TA (°C) R2= ∞ IKA=10mA Ambient Temperature TA (°C) VKA=VREF TA=25 °C Cathode Voltage VKA (V) Fig.7 IKA-VKA Cathode Current IKA (uA) Cathode Current IKA (mA) Fig.6 IKA-VKA VKA=VREF TA=25 °C Cathode Voltage VKA (V) Rev. B/LX www.taitroncomponents.com Page 6 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Fig.9 ∆ VREF -TA ∆ VKA Ratio of Delta Reference Voltage to the Ratio of Delta Cathode Voltage (mV/V) Off-State Cathode Current IKA (off) (uA) ( A) Fig.8 IKA(Off)-TA VKA=36V VREF=0V Ambient Temperature TA (°C) VKA=3.5V to 36V Ambient Temperature TA (°C) Cathode Current IKA (mA) Fig.10 Stability Boundary Conditions Vs. Load Capacitance Stable Stable TA=25°C VKA=VREF VKA=5V:No Oscillation VKA=10V:No Oscillation VKA=15V:No Oscillation Load Capacitance CLOAD (uF) Rev. B/LX www.taitroncomponents.com Page 7 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Fig.11 Small Signal Voltage Gain vs. Frequency Voltage Gain VG (dB) TA=25 °C IKA=10mA Small Signal Frequency f (Hz) Reference Impedance (Ω) Fig.12 Reference Impedance Vs Frequency TA=25 °C IKA=10mA Frequency f (Hz) Rev. B/LX www.taitroncomponents.com Page 8 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Output and Input Voltage VOUT/VIN (V) Fig.13 Pulse Respond of Input and Output Voltage Input Output Time (uS) Rev. B/LX www.taitroncomponents.com Page 9 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Typical Application Circuit Fig.14 Shunt Regulator Fig.16 Current Source or Current Limit Fig.15 High Current Shunt Regulator Fig.17 Precision 5V 1A Regulator Fig.18 PWM Converter With Reference Rev. B/LX www.taitroncomponents.com Page 10 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B Dimensions in mm (inch) TO-92 Buck TO-92 Ammo Rev. B/LX www.taitroncomponents.com Page 11 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B SOT-89 SOT-89 Rev. B/LX www.taitroncomponents.com Page 12 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B SOT-23 SOT-23-5 Rev. B/LX www.taitroncomponents.com Page 13 of 14 Adjustable Precision Shunt Voltage Regulator LM431A LM431B How to contact us: US HEADQUARTERS 28040 WEST HARRISON PARKAWAY, VALENCIA, CA 91355-4162 Tel: (800) TAITRON (800) 824-8766 (661) 257-6060 Fax: (800) TAITFAX (800) 824-8329 (661) 257-6415 Email: [email protected] Http://www.taitroncomponents.com TAITRON COMPONENTS MEXICO, S.A .DE C.V. BOULEVARD CENTRAL 5000 INTERIOR 5 PARQUE INDUSTRIAL ATITALAQUIA, HIDALGO C.P. 42970 MEXICO Tel: +52-55-5560-1519 Fax: +52-55-5560-2190 TAITRON COMPONETS INCORPORATED E REPRESENTAÇÕES DO BRASIL LTDA RUA DOMINGOS DE MORAIS, 2777, 2.ANDAR, SALA 24 SAÚDE - SÃO PAULO-SP 04035-001 BRAZIL Tel: +55-11-5574-7949 Fax: +55-11-5572-0052 TAITRON COMPONETS INCORPORATED, SHANGHAI REPRESENTATIVE OFFICE METROBANK PLAZA, 1160 WEST YAN’ AN ROAD, SUITE 1503, SHANGHAI, 200052, CHINA Tel: +86-21-5424-9942 Fax: +86-21-5424-9931 Rev. B/LX www.taitroncomponents.com Page 14 of 14