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Michael Karas
Michael Karas
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With 10 mA LED current, the 4N25's current transfer ratio is 20% minimum - that would give 2 mA throught the output transistor.

The specs for the fan call for 1 - 2 Amps - there is nowno way the 4N25 can directly drive the fan.

You need to have the opto drive a FET that can handle the 2 Amps the fan may want on starting.

With 10 mA LED current, the 4N25's current transfer ratio is 20% minimum - that would give 2 mA throught the output transistor.

The specs for the fan call for 1 - 2 Amps - there is now way the 4N25 can directly drive the fan.

You need to have the opto drive a FET that can handle the 2 Amps the fan may want on starting.

With 10 mA LED current, the 4N25's current transfer ratio is 20% minimum - that would give 2 mA throught the output transistor.

The specs for the fan call for 1 - 2 Amps - there is no way the 4N25 can directly drive the fan.

You need to have the opto drive a FET that can handle the 2 Amps the fan may want on starting.

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Peter Bennett
Peter Bennett
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With 10 mA LED current, the 4N25's current transfer ratio is 20% minimum - that would give 2 mA throught the output transistor.

The specs for the fan call for 1 - 2 Amps - there is now way the 4N25 can directly drive the fan.

You need to have the opto drive a FET that can handle the 2 Amps the fan may want on starting.