Hi Dale,
I'm hopeful that maybe you got a poorly done batch of clone boards.
I'll do some more testing.
Thanks for your feedback!
73, David KB4FXC
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On Sun, 22 Oct 2017, Master Ice wrote:
Nope they didn't survive because the failure of the regulator meant that, when they blew, they went short circuit and slammed full 12V onto the Atmega.
The ones that I have had fail were all fitted with supposedly genuine (ha ha ha ) AMS1117-5 5V versions of the regulator.
Luckily the problem was dealt with by me before the product went to the client by the simple expedient of kludging a better 5V supply and ignoring the Nano regulator completely.
As an aside I puchased a few sacrificial batches of Chinese AMS1117-5 regulators and found that, on test, less than 50% were capable of handling more than 9V input safely.
Some manufacturers claim an input of <=12V while other claim 15V.
The joys of the game.
Dale G4IPZ
----- Original Message -----
From: Dexter N Muir
To: [email protected]
Sent: Sunday, October 22, 2017 9:24 PM
Subject: Re: [BITX20] I made a mistake
Dale me ol' Chin-wah, commiserations - though if the rest of the chip survives you'll have a ready stock of Nanos to hand! That flaky reg is the reason for the Raduino's 78LM7805 regulator - that and the Nano's current drain being either too close to or over the max spec of a 78L05.
p.s. I've taken my 7805 to the other face of the PCB for heatsink clearance and accessibility. It allows me to sit stuff close to that side of the Raduino
