Datasheet LT1464, LT1465 (Analog Devices) - 7

LT1464/LT1465
U U W U APPLICATIONS INFORMATION Phase Reversal Protection
gain follower mode (Figure 1b) and the response of the LT1464/LT1465 (Figure 1c). Most industry standard JFET input single, dual and quad op amps exhibit phase reversal at the output when the The phase reversal of Figure 1b can cause lock-up in servo negative common mode limit at the input is exceeded. systems. The LT1464/LT1465 does not phase-reverse Common mode range is at a premium at ±5V supplies. The when the common mode input is anywhere within the Figures show a ±5.2V sine wave input (Figure 1a), the supplies. response of a competing JFET input op amp in the unity- LT1464 • F01a LT1464 • F01b
(1a)
±
5.2V Sine Wave (1b) Typical JFET Input Op Amp with
±
5V Supplies
LT1464 • F01c
(1c) LT1464/LT1465 Output with
±
5V Supplies Figure 1. Voltage Follower with Input Exceeding the Common Mode Range (VS =
±
5V)
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