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culation

I am simulating an op-amp circuit of which a small section is shown in the image. As per power consumption formula,

P = Icc * (V+ - V-) + Iout * (V+ - Vout)

I tried to calculate the power. I have put the values shown in the image.

P = 1.17mA (I have confusion in this value) * (5V-(-5v)) + 0.36 mA (5V-2.16V)

P = 11.7 mW + 1.0224 mW = 12.72mW. But the Watt meter probe in simulation shows 4.89mW .

I got a confusion that whether I am missing any point or doing wrong in the calculation?

Clarify this!

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Power consumption of the op amp is different than the power drawn from the supply.

The equation below should give you the power consumed by the op amp I think.

ICC * VCC + IEE * VEE - I(OUT) * V(OUT)

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  • \$\begingroup\$ Tip: You can use HTML entities such as &times; (\$ \times \$) and some markdown such as <sub>...</sub> and <sup>...</sup> for sub- and superscript. \$\endgroup\$
    – Transistor
    Feb 7 '20 at 20:47
  • \$\begingroup\$ Thank you I was wondering how people were doing that \$\endgroup\$
    – dsizzle83
    Feb 10 '20 at 18:27
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I'm confused by the various measurements - DC, p-p and RMS - but just working with the DC I get:

enter image description here

  1. 5.5 mW is provided by VEE.
  2. -0.49 mW is provided by VDC2. I'm not sure how a circuit could do this.
  3. The output current is negative so the op-amp is sinking current so power out is -0.41 mW.

Adding them up I get PIC = PIN - POUT = (5.5 - 0.49) + (-0.41) = 4.6 mW.

That's the best I can make of it.

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