LT1464 LINER [Linear Technology], LT1464 Datasheet - Page 7

• Manufacturer Part Number: LT1464
• Description: Dual/Quad Micropower, 1MHz C-Load Picoampere Bias Current JFET Input Op Amps
• Manufacturer: LINER [Linear Technology]

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