"Fansler, David" wrote:
>
> I am working on a project that uses a PIC to operate 3 logic level HEXFET's
> (IRLIZ44N & IRLD014) that is driving me crazy.  I was under the impression
> that logic level HEXFET's would (when +5V is applied to the gate) would open
> up an pass whatever voltage was on the drain to the source (within the
> limits of the device).  Ain't happening.  All I get is 6 - 7 v through the
> device, with 24vdc on the drain.  And yes, I do have the gate, drain, source
> pins correctly identified.  I have tried high side, low side and would try
> third side if I knew how.
>
> Basic circuit is
>                 +24vdc
>               |
>                 Drain
>  +5V------Gate
>                 Source
>               |
>            24 vdc relay coil
>               |
>              GND
>
> To date I have not even put the PIC in the circuit, but rather just fed 5v
> from the power supply.
> Any ideas or help would be greatly appreciated - I am beginning to doubt my
> manhood!
> Thanks
> David

Perhaps put the relay on the drain side, with a protection diode.

--
Best regards

Tony

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