enter image description here I ran this simulation in ltspice and my output voltage was -2.97V. According to my calculations I should have roughly -10V when all sources are at 5V.
$$V_{out} = -V_{in}R_5 \left ( \frac{1}{R_1} + \frac{1}{R_2}+\frac{1}{R_3}+\frac{1}{R_4}\right )$$ I tried this same circuit on partsim's online simulator and got -9.97V. Is there something missing in the LTSpice circuit?

  • \$\begingroup\$ Did you try an ideal op-amp instead? \$\endgroup\$ – uint128_t May 6 '17 at 3:31

According to the front page of the datasheet, the LT1022 is able to produce 20 mA from its output. With 133 ohms in the feedback resistor, this will allow it to produce only 2.66 V.

The front page generally doesn't give true specifications, but if you look into the actual specs, they don't tell you anything about the output swing when the load resistance is less than 2 kohms, and the specs they give don't guarantee any more than 6 mA output current.

Your simulation seems to show that 20 mA is indeed possible for a typical part, as modeled by whoever developed the LT1022 model for LTSpice.

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  • \$\begingroup\$ Ahh, I see now! I totally missed that aspect of the sim. thanks @Photon \$\endgroup\$ – user64054 May 6 '17 at 17:29

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