Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

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By Stoney
#26080
martinayotte wrote:
Stoney wrote:I don't think so, unless I am misunderstanding what you are saying.
the current does not ramp up till the snap back voltage at 5.8v.
have a look at the graph on bottom left page 122 here .. Id remains low till Vd is well over 5V
http://www.fujitsu.com/downloads/MAG/vol39-1/paper14.pdf


Could you, please provide details, because this PDF has only 9 pages, and you mentioned bottom left of page 122 ?

Stoney wrote:In my own case I will use a voltage divider or a proper 3.3v interface, but we have many non electronics types using this device however with no access to soldering irons and resistors handy, I keep seeing the same info saying 5v will kill the device and it CANNOT be used with 5v data, I would like to be able to offer both sane and correct advice wherever possible. Hence the fact checking thread :)


So, is that you mean that you agree with what I've said above "we should NEVER rely on that" ?


it is a book extract, page numbers are on the bottom of the pages,the page with the number 122 on it has the diagram i was referring too..

I was saying I am not going to rely on that, as in long term, if I made a device talking to a 5v micro then I would add a divider, however if it is to program a device then I can and should be able to rely on the fact the thing is not going to fail in the short term. I personally, would not.
In all likelihood given the reason they are using this more expensive ESD protection is to provide 5v tolerance to data pins, then I quite probably could rely on that long term.
many decades of electronics though make some habits hard to break, you sound the same.
If asked however, I would at this point tell people .. yes, you are almost certainly safe to use the device with 5v data, the datasheet is somewhat confusing, 3.6V is listed as max input and you are best served following this advice, I would suggest using a divider if you have the components to hand.

Vdd, different matter .. I am considering trying one unregulated on a solar charged lithium at up to 4.2, reason being that no wasted current for a regulator, no wasted voltage on a regulator, no sag on tx current due to a regulator, less components and maybe even a bonus increased range due to higher voltage on the RF section. Possibly to illegal power levels but hey, I have no neighbours,
Would I ever give one to someone else, no .. but I am happy to stick one in my chook shed to see how it goes. All reports are that sleep currents remain low till 4.5v at which point the device is starting to avalanche.