MOSFETS stay hi when reset pulled low

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RES
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Posted by RES: Fri. Jan 27, 2006 - 07:38 PM
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When I dump a new program in the AVR, the MOSFETS at the pins stay hi, because the pins go in hi-Z. What I see is the datadump on the LEDs. (because I use ISP pins/MOSFET gates)
What can be done about this?
I think some resistors from the gate to GND? But what value?

Thanks.

RES

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AVR Microcontrollers, megaAVR and tinyAVR
Last Edited: Fri. Jan 27, 2006 - 07:47 PM
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zoomcityzoom
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Posted by zoomcityzoom: Fri. Jan 27, 2006 - 07:40 PM
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100K Ohm resistors will work nicely.

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ka7ehk
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Posted by ka7ehk: Fri. Jan 27, 2006 - 07:42 PM
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Yes, 100K would be good. Probably anything down to 1K would also be OK. Very non-critical.

Jim

 

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sutton
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Posted by sutton: Fri. Jan 27, 2006 - 08:32 PM
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You do need to bare in mind the voltage divider affect of a pull down if you have a resistor in series with the drive pin.

Keep it simple it will not bite as hard

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