Swap Zener 3.3v for 3.6v ok?

USB AVR Programmer and SPI interface. Adafruit's USBtinyISP.

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robynbanks
 
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Swap Zener 3.3v for 3.6v ok?

Post by robynbanks »

Hi there, I recently purchased a USBtinyISP kit from jameco and it was missing one of the 3.6v Zener diodes. I have a 3.3v one and was wondering if I could use that instead of ordering and waiting etc.

Thank you!

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dastels
 
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Re: Swap Zener 3.3v for 3.6v ok?

Post by dastels »

Impossible to know without knowing what it's doing in the circuit, but without that I would say no... it's 3.6v for a reason.

Dave

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marshaj847
 
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Re: Swap Zener 3.3v for 3.6v ok?

Post by marshaj847 »

looking at a schematic https://cdn-learn.adafruit.com/assets/a ... sp2sch.png
D1 and D2 seem to be voltage clamping on the USB data lines...
while it might not be a problem for short term use, since the USB programming cable is short, a long cable might have signal degradation issues mentioned in this posting
https://electronics.stackexchange.com/q ... -high-3-3v

Marsha

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