OP97

Rev. G | Page 12 of 16

AC PERFORMANCE

The ac characteristics of the OP97 are highly stable over its full

operating temperature range. Unity-gain small-signal response

is shown in Figure 30. Extremely tolerant of capacitive loading

on the output, the OP97 displays excellent response even with

1000 pF loads (see Figure 31). In large signal applications, the

input protection diodes effectively short the input to the output

during the transients if the amplifier is connected in the usual

unity-gain configuration. The output enters short-circuit current

limit, with the flow going through the protection diodes.

Improved large signal transient response is obtained by using a

feedback resistor between the output and the inverting input.

Figure 32 shows the large-signal response of the OP97 in unity-

gain with a 10 kΩ feedback resistor. The unity-gain follower

circuit is shown in Figure 33.

The overcompensation pin (Pin 5) can be used to increase the

phase margin of the OP97 or to decrease gain bandwidth

product at gains greater than 10.

20mV

5µs

100

90

10

0%

Figure 30. Small Signal Transient Response

(CLOAD = 100 pF, AVCL = 1)

100

90

10

0%

20mV

5µs

100

90

10

0%

20µs

2V

Figure 31. Small-Signal Transient Response

(CLOAD = 1000 pF, AVCL = 1)

Figure 32. Large Signal Transient Response (AVCL = 1)

VOUT

VIN

OP97

10kΩ

2

3

6

Figure 33. Unity-Gain Follower

100

90

10

0%

20mV

5µs

Figure 34. Small Signal Transient Response with Overcompensation

(CLOAD = 1000 pF, AVCL = 1, COC = 220 pF)