I want to use AD844 op amp to amplify signals at about 11 MHz.

I just want to build the following circuit configurations: inverting gain of 1, 10 and non-inverting gain of 1, 10 and 100.

These configurations have also be illustrated in the datasheet. But I could not see any clear hint about what to do with the TZ pin and the null pins if I do not want to use them.

Now my question is, what should I do with the TZ pin and the null pins, in light of what I want to do with the op amp, as I have mentioned. Should I keep them disconnected, or connect to ground, or what?

Here is a link to the datasheet:


  • \$\begingroup\$ You won't get a gain of 100 at 11 MHz. \$\endgroup\$
    – Andy aka
    Jun 30 '21 at 13:13
  • \$\begingroup\$ It's a high speed op amp and it’s meant to do that. \$\endgroup\$
    – shafik
    Jun 30 '21 at 13:41
  • \$\begingroup\$ Non-inverting (gain of 100) 3 dB point is typically 9 MHz on +/-15 volt rails and typically 5 MHz on +/- 5 volt rails but, if you say you can achieve 11 MHz bandwidth with gain at +100 then good luck. \$\endgroup\$
    – Andy aka
    Jun 30 '21 at 14:05
  • \$\begingroup\$ Ok. You are right, the gain at 11 MHz would not be 100 (or 70). Hope gain of 50 (or 40) would work. This was not my actual question though. \$\endgroup\$
    – shafik
    Jun 30 '21 at 14:26

You should keep the NULL and TZ pins disconnected, if you don't need them.

  • \$\begingroup\$ Thanks bro. You sure about that? \$\endgroup\$
    – shafik
    Jun 30 '21 at 13:49
  • 1
    \$\begingroup\$ Yes, because it reads in the datasheet you linked that the use of those pins is optional, and the examples that do not use those pins don't even mention those pins. \$\endgroup\$
    – Justme
    Jun 30 '21 at 13:53
  • \$\begingroup\$ Ok. Hope you are correct. (I think you are.) \$\endgroup\$
    – shafik
    Jun 30 '21 at 14:15

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