TECHNICAL DATA TL431 Programmable Precision Reference FEATURES PIN CONNECTIONS • Programmable Output Voltage to 40V • Low Dynamic Output Impedance 0.2Ω • Sink Current Capability of 0.1 mA to 100 mA • Equivalent Full-Range Temperature Coefficient of 50 ppm/oC • Temperature Compensated for Operation over Full Rated Operating Temperature Range • Low Output Noise Voltage • Fast Turn on Response ANODE • TO-92, SOP- 8, SOT-23, SOT-89 packages REFERENCE CATHODE DESCRIPTION The TL431 is a three-terminal adjustable regulator series with a guaranteed thermal stability over applicable temperature ranges. The output voltage may be set to any value between Vref (approximately 2.5 volts) and 40 volts with two external resistors. These devices have a typical dynamic output impedance of 0.2Ω. Active output circuitry provides a very sharp turn-on characteristic, making these devices excellent replacement for zener diodes in many applications. o o The TL431 is characterized for operation from -25 C to +85 C. SYMBOL FUNCTIONAL BLOCK DIAGRAM ABSOLUTE MAXIMUM RATINGS (Operating temperature range applies unless otherwise specified) Characteristic Cathode Voltage Cathode Current Range (Continuous) Reference Input Current Range o Symbol Value Unit VKA 40 V IK -100 ~ 150 mA IREF 0.05 ~ 10 mA 0.7 0.2 W W Power Dissipation at 25 C: o SOP, TO – 92 Package (RJA = 178 C/W) o SOT Package (RJA = 625 C/W) PD Junction Temperature Range TJ -40 ~ 150 o Operating Temperature Range Tg -40 ~ +85 o -65 ~ +150 o Storage Temperature Range Tstg C C C Rev. 00 TL431 RECOMMENDED OPERATING CONDITIONS Characteristic Symbol Test Condition Min Typ Max Unit Cathode Voltage VKA VREF 40 V Cathode Current IK 0.5 100 mA ELECTRICAL CHARACTERISTICS (Ta = 25oC, VKA = VREF, IK = 10mA unless otherwise specified) Characteristic Min Typ Max 2.440 2.495 2.550 2.470 2.495 2.520 2.482 2.495 2.508 3 17 ΔVKA = 10V-VREF -1.4 -2.7 ΔVKA = 36V- 10V -1.0 -2.0 IREF R1 = 10KΩ, R2 = ∞ 1.8 4 ㎂ Deviation of Reference Input Current Over Full Temperature Range IREF(dev) R1 = 10KΩ, R2 = ∞ 0.4 1.2 ㎂ Minimum Cathode Current for Regulation IK(min) 0.25 0.5 mA Off-State Cathode Current IK(off) VKA = 40 V, VREF = 0 0.26 0.9 ㎂ Dynamic Impedance ZKA IK = 10mA to 100 mA , f ≤ 1.0KHz 0.22 0.5 Ω Reference Input Voltage Symbol Test Condition VREF VKA = VREF, IK = 10mA TL431 (2%) TL431-A (1%) Unit V TL431-C (0.5%) Deviation of Reference Input Voltage Over Full Temperature Range VREF(dev) Ratio of Change in Reference Input Voltage to the Change in Cathode Voltage ΔV REF ΔV K A Reference Input Current Tmin ≤ Ta ≤ Tmax MV mV/V TEST CIRCUITS Figure 1. Test Circuit for V KA = VREF Figure 2. Test Circuit for V KA ≥ VREF Figure 3. Test Circuit for I off INPUT VK A I K (OFF) TL431 TL431 BT432 TL431 Rev. 00 TL431 Electrical Characteristics (Continued) The average temperature coefficient of the reference input voltage, ∝VREF, is defined as: Where: T2 − T1 = full temperature change (0-70˚C). ∝VREF can be positive or negative depending on whether the slope is positive or negative. Example: VDEV = 8.0 mV, VREF = 2495 mV, T2 − T1 = 70˚C, slope is positive. Note 6: The dynamic output impedance, rZ, is defined as: When the device is programmed with two external resistors, R1 and R2, (see Figure 2 ), the dynamic output impedance of the overall circuit, rZ, is defined as: Rev. 00 TL431 Equivalent Circuit Typical Performance Characteristics Input Current vs VZ Thermal Information Input Current vs VZ Dynamic Impedance vs Frequency Rev. 00 TL431 Typical Performance Characteristics (Continued) Stability Boundary Conditions Note: The areas under the curves represent conditions that may cause the device to oscillate. For curves B, C, and D, R2 and V+ were adjusted to establish the initial VZ and IZ conditions with CL = 0. V+ and CL were then adjusted to determine the ranges of stability. Test Circuit for Curve A Above Typical Applications Shunt Regulator Test Circuit for Curves B, C and D Above Single Supply Comparator with Temperature Compensated Threshold Rev. 00 TL431 Typical Applications (Continued) Higher Current Shunt Regulator Series Regulator Crow Bar Output Control of a Three Terminal Fixed Regulator Rev. 00 TL431 Typical Applications (Continued) Over Voltage/Under Voltage Protection Circuit Voltage Monitor Rev. 00 TL431 Typical Applications (Continued) Current Limiter or Current Source Delay Timer Constant Current Sink Rev. 00 TL431 Ordering Information Reference Input Voltage Product Number TL431CLF TL431CLS TL431CD TL431CS TL431CP TL431ALF TL431ALS TL431AD TL431AS TL431AP TL431LF TL431LS TL431D TL431S TL431P Package TO-92 0.5% 8-SOP SOT-23 SOT-89 TO-92 1% 8-SOP SOT-23 SOT-89 TO-92 2% 8-SOP SOT-23 SOT-89 Package Dimensions D SUFFIX SOIC (MS - 012AA) Dimension, mm A 8 5 B H 1 G P 4 D K MIN MAX A 4.80 5.00 B 3.80 4.00 C 1.35 1.75 D 0.33 0.51 F 0.40 1.27 R x 45 C -T- Symbol SEATING PLANE J F 0.25 (0.010) M T C M NOTES: 1. Dimensions A and B do not include mold flash or protrusion. 2. Maximum mold flash or protrusion 0.15 mm (0.006) per side for A; for B ‑ 0.25 mm (0.010) per side. M G 1.27 H 5.72 J 0° 8° K 0.10 0.25 M 0.19 0.25 P 5.80 6.20 R 0.25 0.50 Rev. 00 TL431 TO-92 Rev. 00 TL431 Rev. 00 TL431 Rev. 00