Putting diodes in parallel
The diode &quot;forward voltage&quot; (or forward voltage with ohmic resistance) is a simplified heuristic model that assumes that the diode's voltage is nearly constant with forward current, but this model breaks down (is not accurate) when dealing with interactions near that voltage threshold. The schockley diode equation is a better model of the diode's V-I curve under those conditions.
Usually in the data sheet for the diode you can find a &quot;typical operating characteristic&quot; plot of the V-I curve.