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I want to transform my 0-5V analog signal to differential signals. I have on hand a bunch of TI INA106KP. I'd like to use one to invert my signal and the other one to non-inverting. The doc show how to get a inverting and a buffer. The buffer however has a gain of 11. Can I still use the two together?

also, is a simple voltage divider good enough to power this? I want to run my signal down 20ft of shielded twisted pair wires.

Schematics

enter image description here

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Ground the 100K resistor (Pin1) in the first example, rather than connecting it to the input, to get a gain of +10.0 for the non-inverting side.

I don't know what you mean by power it through a voltage divider. It should have a power supply of something like +10V and -10V regulated to work properly. +/-15V is what it is specified with.

20 feet of shielded twisted pair wires will be okay, provided the capacitance of the wire does not exceed 50pF/foot, otherwise the amplifier may go unstable. You should also consider protecting the outputs of the amplifier with some hefty TVS bipolar diodes. It would be better if you could put at least 100 ohms in series with each output.

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  • \$\begingroup\$ The opamp has a minimum +/- 5v requirement, can I go with that? I wanted to use a voltage divider to create a virtual ground and +5,-5 like :tangentsoft.net/elec/bitmaps/vgrounds/buffer.png \$\endgroup\$ – mugetsu Jul 30 '14 at 19:04
  • \$\begingroup\$ If you look at page 4, you can see that +/-2V is plausible with +/-5V supplies, so if you divide the 0-5V input by 25:1 you can get +/-2V outputs (+/-4V differential voltage). The power supply question will require a schematic showing where the input signal common will be connected. \$\endgroup\$ – Spehro Pefhany Jul 30 '14 at 19:09
  • \$\begingroup\$ Trying the above circuits with just a constant voltage input of 12v, the inverter gets me -11v and the buffer gets me 8v. Is this ok? \$\endgroup\$ – mugetsu Jul 31 '14 at 0:53
  • \$\begingroup\$ Nope. Show your schematic, please. \$\endgroup\$ – Spehro Pefhany Jul 31 '14 at 0:56
  • \$\begingroup\$ just did, sorry for the crudeness \$\endgroup\$ – mugetsu Jul 31 '14 at 1:22

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