link to page 4 link to page 4 LM431SA, LM431SB, LM431SCELECTRICAL CHARACTERISTICS (Continued) (Notes 7 and 8, Values are at TA = 25°C unless otherwise noted) LM431SAILM431SBILM431SCISymbolParameterConditionsMin. Typ. Max. Min. Typ. Max. Min. Typ. Max. Unit VREF Reference Input VKA = VREF, IKA = 10 mA 2.450 2.500 2.550 2.470 2.495 2.520 2.482 2.495 2.508 V Voltage VREF(dev) Deviation of Refer- VKA = VREF, IKA = 10 mA, TMIN ≤ TA ≤ ence Input Voltage TMAX 5 20 5 20 5 20 mV Over−Temperature DVREF / Ratio of Change in IKA = 10 mA DVKA = 10 V−VREF −1.0 −2.7 −1.0 −2.7 −1.0 −2.7 mV/V DVKA Reference Input Volt- age to Change in DV Cathode Voltage KA = 36 V − 10 V −0.5 −2.0 −0.5 −2.0 −0.5 −2.0 IREF Reference Input IKA = 10 mA, R1 =10 KW, R2 = ∞ 1.5 4.0 1.5 4.0 1.5 4.0 μA Current IREF(dev) Deviation of Refer- IKA = 10 mA, R1 = 10 KW, R2 = ∞, 0.8 2.0 0.8 2.0 0.8 2.0 μA ence Input Current TMIN ≤ TA ≤ TMAX Over Full Temperature Range IKA(MIN) Minimum Cathode VKA = VREF 0.45 1.00 0.45 1.00 0.45 1.00 mA Current for Regulation IKA(OFF) Off −Stage Cathode VKA = 36 V, VREF = 0 0.05 1.00 0.05 1.00 0.05 1.00 μA Current ZKA Dynamic Impedance VKA = VREF, IKA = 1 to 100 mA, 0.15 0.50 0.15 0.50 0.15 0.50 W f ≥ 1.0 kHz 7. LM431SAI, LM431SBI, LM431SCI: − TA(min) = −40_C, TA(max) = +85_C All other pins: − TA(min) = −25_C, TA(max) = +85_C 8. The deviation parameters VREF(dev) and IREF(dev)are defined as the differences between the maximum and minimum values obtained over the rated temperature range. The average full−range temperature coefficient of the reference input voltage, αVREF, is defined as: ǒ VREF(dev) Ǔ@106 VREF(at 25°C) |aV Ǔ where T REF|ǒppm °C + T MAX −TMIN is the rated operating free−air temperature range MAX * TMIN of the device. aVREF can be positive or negative, depending on whether minimum VREF or maximum VREF, respectively, occurs at the lower VREF(min) temperature. Example: VREF(dev) VREF(dev) = 4.5 mV, VREF = 2500 mV at 25°C, TMAX −TMIN = 125°C for LM431SAI. VREF(max) ǒ 4.5mV Ǔ@106 2500 mV |aVREF| + 125°C + 14.4 ppmń°C TMAX -TMIN Because minimum VREF occurs at the lower temperature, the coefficient is positive. www.onsemi.com4