Precision Adjustable Shunt Reference CORPORATION TL431 FEATURES DESCRIPTION • • • • • • The TL431 is an adjustable shunt regulator designed to act as an open-loop error amplifier with a 2.5V temperature compensated reference. Its highly accurate 1% bandgap reference is perfect for applications requiring stability and accuracy over temperature and life. Trimmed 1% Bandgap Reference Nominal Temperature Range Extended to 105oC Temperature-Compensated: 30ppm/ oC Internal Amplifier with 150mA Capability Low Output Noise Low Frequency Dynamic Output Impedance Sharp turn-on characteristics and a low temperature coefficient make the TL431 an excellent replacement for many zener diode applications, programmable to any value greater than 2.5V and up to 36V by using two external resistors. As a combination error amplifier and reference, it can be used to manage control loops such as switching power supplies. ORDERING INFORMATION Part Package TL431LP TL431D TL431S TO-92 8-Pin Plastc SOIC SOT-89 Temperature Range 0 to 105oC 0 to 105oC 0 to 105oC PIN CONFIGURATION (Top View) SOIC (D) TO-92 (LP) SOT-89 (S) CATHODE 1 8 REFERENCE ANODE 2 7 ANODE ANODE 3 6 ANODE N/C 4 5 N/C CATHODE ANODE REFERENCE CATHODE ANODE REFERENCE 1G-34 1G-33 1G-35 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 TL431 CORPORATION ABSOLUTE MAXIMUM RATINGS SYMBOL PARAMETER RATING UNITS VKA Cathode-Anode Reverse Breakdown 37 V IAK Anode-Cathode Forward Current 1 A IKA Operating Cathode Current 250 mA IREF Reference Input Current 10 mA PD Continuous Power at 25 oC TO-92 8L SOIC SOT-89 775 750 1000 mW mW mW TJ Junction Temperature 150 o C TSTG Storage Temperature –65 to 150 o C TL Lead Temperature, Soldering 10 Seconds 300 o C Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. RECOMMENDED CONDITIONS SYMBOL TYPICAL THERMAL RESISTANCE PARAMETER RATING UNIT PACKAGE θJA o θJC o TYPICAL DERATING VKA Cathode Voltage VREF to 20 V TO-92 160 C/W 80 C/W 6.3mW/oC IK Cathode Current 10 mA SOIC 175 oC/W 45 oC/W 5.7mW/oC SOT-89 110oC/W 8oC/W 9.1mW/oC FUNCTIONAL BLOCK DIAGRAM CATHODE (K) REFERENCE (R) + – 2.5V ANODE (A) 1G-36 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 TL431 CORPORATION ELECTRICAL CHARACTERISTICS Electrical Characteristics are guaranteed over full junction temperature range (0 to 105oC). Ambient temperature must be derated based on power dissipation and package thermal characteristics. The conditions are: VKA = VREF and IK = 10mA unless otherwise stated. SYMBOL VREF PARAMETER Reference Voltage MIN TYP MAX UNIT TEST CIRCUIT 2.470 2.495 2.520 V 1 TA = 25oC 2.541 V 1 Over Temp. 2.449 TC ∆VREF with Temp.* 0.07 o 0.20 ∆VREF ∆VK Ratio of Change in VREF to Cathode Voltage IREF Reference Input Current 0.7 4 –2.7 –1.0 –2 –0.4 0.3 mV/ C 1 mV/V 2 TEST CONDITION VREF to 10V 10V to 36V µA 2 ∆IREF IREF Temp Deviation 0.4 1.2 µA 2 IK(MIN) Min IK for Regulation 0.4 1 mA 1 IK(OFF) Off State Leakage 0.04 250 nA 3 VREF = 0V, VKA = 36V ZKA Dynamic Output Impedance 0.15 0.5 Ω 1 f ≤ 1kHz, I K = 1 to 150mA Over Temp. mV ppm *CALCULATING AVERAGE TEMPERATURE COEFFICIENT (TC) % 0 0 • TC in mV/oC = 0 ∆VREF ∆T –10 5000 0.5 • TC in %/oC = 0 15 30 45 60 75 90 ∆VREF (mV) ∆TA ∆VREF o VREF at 25 C 105 TEMPERATURE (˚C) o • TC in ppm/ C = 0.07 mV/˚C x 100 ∆TA ∆VREF o VREF at 25 C x 106 ∆TA 0.003 %/˚C 27 ppm/˚C 1G-37 TEST CIRCUITS V IN V KA = V REF V IN V KA IK IK I REF R1 V IN V KA I K(OFF) I REF (V REF ) R2 1G-38 1G-39 TEST CIRCUIT 1 TEST CIRCUIT 2 1G-40 TEST CIRCUIT 3 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 TL431 CORPORATION TYPICAL PERFORMANCE CURVES TEMPERATURE RANGE: –55 to 125˚C 700 600 500 400 125˚C 300 25˚C 200 –55˚C 100 0 –100 –200 –1.0 0 1.0 2.0 3.0 VKA – CATHODE VOLTAGE (V) 1G-41 10 1 0.1 75 50 25 0 –25 –50 –75 –1 0 1 2 VKA – CATHODE VOLTAGE (V) 3 1G-42 VKA = VREF 2.53 I K = 10mA 2.52 2.51 2.50 VREF = 2.503V AT 25˚C 2.49 2.48 2.47 2.46 –60 1G-43 REFERENCE INPUT CURRENT 2.0 1.5 1.0 0.5 –10 1G-44 –55˚C 0˚C –20 25˚C 75˚C –30 125˚C –40 I K = 10mA –50 TEMPERATURE RANGE: –55 to 125˚C 0 1G-45 –30 0 30 60 90 120 TA – AMBIENT TEMPERATURE REFERENCE VOLTAGE LINE REGULATION 0 R1 = 10kΩ R2 = ∞ 2.5 I K = 10mA 0 0 30 60 90 120 –60 –30 TA – AMBIENT TEMPERATURE (˚C) 100 2.54 VKA = 36V VREF = 0V 3.0 VKA = VREF TEMPERATURE RANGE: –55 to 125˚C TEMPERATURE COEFFICIENT AS A FUNCTION OF TRIM VALUE OFF STATE LEAKAGE 0.01 0 30 60 90 120 –60 –30 TA – AMBIENT TEMPERATURE (˚C) 125 HIGH CURRENT OPERATING CHARACTERISTICS –100 –2 VREF – REFERENCE VOLTAGE (V) I Z off – OFF STATE CATHODE CURRENT (nA) 100 I REF – REFERENCE INPUT CURRENT (µA) 150 VKA = VREF I K – CATHODE CURRENT (mA) 800 VREF – CHANGE IN REFERENCE VOLTAGE (mV) I K – CATHODE CURRENT (µA) 900 LOW CURRENT OPERATING CHARACTERISTICS 3 6 9 12 15 18 21 24 27 30 VKA – CATHODE VOLTAGE (V) 1G-46 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 TL431 CORPORATION TYPICAL PERFORMANCE CURVES (continued) NOISE VOLTAGE 0.150 Z KA – DYNAMIC IMPEDANCE (Ω) NOISE VOLTAGE nV/ Hz 70 60 50 40 30 20 VKA = VREF 10 I K = 10mA TA = 25˚C 0 100 1k 10k 10 f – FREQUENCY (Hz) Z KA – DYNAMIC IMPEDANCE (Ω) A V – SMALL SIGNAL VOLTAGE GAIN (dB) VKA = VREF I KA = 1 TO 100mA f ≤ 1kHz 0.100 0.075 0.050 0.025 0.0 –60 1G-47 –30 0 30 60 90 120 TA – FREE AIR TEMPERATURE 1G-48 DYNAMIC OUTPUT IMPEDANCE TA = 25˚C I K = 1 TO 100mA 10 1.0 0.1 0.01 1k 70 0.125 100k 100 LOW FREQUENCY DYNAMIC OUTPUT IMPEDANCE 10k 100k 1M f – FREQUENCY (Hz) 10M 1G-49 SMALL SIGNAL GAIN vs FREQUENCY OUT 60 50 15k TA = 25˚C I K = 10mA 9µF IK 230Ω 40 30 8.25k GND 20 1H-01 10 0 1k 10k 100k 1M f – FREQUENCY (Hz) 10M 1G-50 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 TL431 CORPORATION INPUT AND OUTPUT VOLTAGES (V) TYPICAL PERFORMANCE CURVES (continued) 6 PULSE RESPONSE INPUT INPUT MONITOR 5 220Ω OUT 4 3 OUTPUT 50Ω f P = 100kHz 2 1 GND 0 1H-03 –1 0 1 2 3 4 5 6 7 8 9 10 11 12 t – TIME (µs) 1H-02 I K – CATHODE CURRENT (mA) 100 90 80 STABILITY BOUNDARY CONDITIONS A: VKA = VREF 150 Ω B: VKA = 5V AT I K = 10mA C: VKA = 10V AT I K = 10mA D: VKA = 15V AT I K = 10mA IK 70 60 50 STABILITY REGION C 40 10k 30 A 20 10 CL B TA = 25˚C 1H-05 D 0 100 101 102 103 104 105 106 107 C L – LOAD CAPACITANCE (pF) 1H-04 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025