Pulsed collector current 4n33 optoisolator?

150 is the absolute max. I try to avoid designing to the maximum. also with Vsat at 1V, 300 mA at 50% duty cycle, you will see 150mW dissipation. This is the spec'd max also. I'd avoid it.

why use an opto? you aren't getting isolation. why not just use a couple of transistors?
 
unless there are more optos that aren't shown, you are only getting isolation on the 2 CA pins and none of the others. To me, isolation isn't a percentage thing - either you have it or you don.t. also, the power supply needs to be isolated.

when I design isolated circuits, I create a "dmz" that has no electrical connections across it. including the power supply.
 
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You need driver transistors.

The optos could drive two PNP transistors which would drive the display.
 
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