LT1462/LT1463 UUWUAPPLICATIONS INFORMATIONPhase Reversal Protection response of a competing JFET input op amp in the unity- gain follower mode (Figure 1b) and the response of the Most industry standard JFET input single, dual and quad LT1462/LT1463 (Figure 1c). op amps exhibit phase reversal at the output when the negative common mode limit at the input is exceeded. The phase reversal of Figure 1b can cause lock-up in servo Common mode range is at a premium at ±5V supplies. The systems. The LT1462/LT1463 does not phase-reverse when Figures show a ±5.2V sine wave input (Figure 1a), the the common mode input is anywhere within the supplies. LT1462 • F01a LT1462 • F01b (1a) ± 5.2V Sine Wave(1b) Typical JFET Input Op Amp with ± 5V Supplies LT1462 • F01c (1c) LT1462/LT1463 Output with ± 5V SuppliesFigure 1. Voltage Follower with Input Exceeding the Common Mode Range (VS = ± 5V) 7