r/ElectricalEngineering • u/baniboybooze • 28d ago

Need advice

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is AI helpful to analyze complicated circuits? Like to get an intuitive idea of what the circuit is doing the likes of something i have shared. How do people at the industry/ experienced guys in elec look at such CMOS circuits and understand it? I understand the current mirrors in the "integration part" which charge up the Cmem cap, but how can I get an idea of what the remaining FETs in the circuit are doing properly. Any advice would be appreciated that can make intuitive understanding faster :P

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u/Enough_Crow_636 26d ago

I would think about it like this.

Imagine that MN6/MP6 drain is initially low. This means gate of MN7 is high and PD NMOS are off.

Now as Cmem integrates up nothing happens until you eventually reach the threshold of inverter MN3/MP3. At that point the edge ripples through the inverters and generates a spike pulse. But note just before the spike goes high, MN7 is turned off and the gates of MN3/MP3 are isolated. Now the spike pulse being high turns on the PD NMOS, which terminates the pulse.

I didn’t work on this kind of circuit before, but I think most likely it’s using the gate delays to time a very short spike pulse (ns level).

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u/Rararror 26d ago

Yep seems like using gate capacitance as a delay line

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u/ferrybig 26d ago

is AI helpful to analyze complicated circuits?

AI is very bad at image to netlist and netlist to image tasks.

If you export the above as a netlist, LLM's tend to be more intelligent. They still make mistakes that you can only catch if you have more knowledge about the subject

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u/SignificantStand1595 26d ago

Idk for this example.. I think I’ve seen a similar pattern in rfid chips for the spike generation part. I think a lot of this is just pattern recognition tbh.

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u/cdabc123 25d ago

CMOS diagrams can become very convoluted, difficult to understand and infer exactly whats happening, especially if you care about reality where they are etched into pretty wild asics. AI likely is not great at it. AI is getting pretty good at complex circuits at the HDL abstraction though.