DanielLam
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Hi,
I'll try to help by making a few points. There isn't really a standard way of reporting power. People will just state what is included in their power measurements, and you have to filter those results to compare ADCs.
1) It is usually tricky to compare power against other SAR ADCs because you it might be hard to figure out what is included and not included. For example, some papers do not include input buffer or reference buffer power, which could be higher than the ADC power itself. Another example might be an ADC with digital calibration, and the big DSP power is not included. To add onto this, some chips might have such a big bypass capacitor on-chip such that they do not require reference buffers. So their design would consume less power, but takes a ton of area.
2) Higher sampling frequency and higher resolution ADCs typically use more power. So you might try to compare using a figure-of-merit (FOM). If the ADCs are distortion limited, use the Walden. If the ADCs are noise limited, use the Schreier. The cutoff point is about 10 ENOB, but you can calculate both and see.
3) There has been extensive work comparing the switching energy of different SAR ADCs. I think these are fair comparisons in terms of DAC swtching power. Although, in some switching schemes you may need Vref and Vcm, and require two reference buffers instead of one. So the power calculation can get tricky here as well.
4) If you want a rough estimate, go through all the digital codes (full sine wave) and average. If possible, include reference and input buffer power. Also, use extracted layouts if you have them.
5) Different codes will use different amounts of energy. So you cannot just use one bit conversion or one sample.
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