Does connecting between two series diodes suppress noise?
I redrew the circuit in a way that is more commonly presented. The reason why we like this form is that it makes it very easy to see what is happening. It's the same reason why we have standard form for equations because you can visually extract the necessary information. So using "standard topologies" also make it easy to see what's happening.

If the voltage on the HBRIDGE A line were to exceed VCC+VD, then D3 would conduct and thereby clamping the voltage to VCC+VD.

If the voltage on the HBRIDGE A line were to drop below -VD, then D2 would conduct and thereby clampig voltage to -Vd.

The same logic applies to the HBRIDGE B line.

Vcc is whatever the supply voltage is.
Vd is whatever the diodes forward drop is. 







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