You got it- 
 
Regards,
John M. Wettroth
(984) 329-5420 (home)
(919) 349-9875 (cell) 
From: The MacDougals <[email protected]> 
Sent: Thursday, August 26, 2021 9:25 AM
To: [email protected]
Subject: RE: [TriEmbed] Measure uA
 
I assume you mean using a 330 ohm as a shunt resistor in series with the load 
(not across the load).
Measure the voltage between the R and the load and use Ohm’s law to calculate 
the resistance of the load and then calculate amps.
 
---> Paul
 
 
From: John Wettroth <[email protected] <mailto:[email protected]> > 
Sent: Wednesday, August 25, 2021 6:16 PM
To: [email protected] <mailto:[email protected]> 
Cc: TriEmbed <[email protected] <mailto:[email protected]> >
Subject: RE: [TriEmbed] Measure uA
 
This might sound barbaric but here’s a really good way for about 1 cent.  Use a 
330 ohm resistor and a DVM that can resolve 10 millivolts- any good Fluke will 
do this.  You’ll drop your load across the R and do a little ohms law and 
voila.  If it’s a sleep current and the unit can draw big currents too, put a 
little switch across the resistor and don’t open the switch until you’re in 
sleep.  It’s a nice old trick that I’ve used for years.
 
Regards,
John M. Wettroth
(984) 329-5420 (home)
(919) 349-9875 (cell) 
From: TriEmbed <[email protected] 
<mailto:[email protected]> > On Behalf Of The MacDougals via 
TriEmbed
Sent: Wednesday, August 25, 2021 4:55 PM
To: [email protected] <mailto:[email protected]> 
Subject: [TriEmbed] Measure uA
 
I want to measure DC current of ESP8266 while in deep sleep.
Should be around 19uA.
 
I recall Dave Jones had a device that turned a volt meter into an amp meter.
https://www.eevblog.com/product/ucurrentgold/
 
I found this clone:
https://github.com/nfhw/tinycurrent
 
Looks like it is available assembled from Germany for 60.50 €
https://www.n-fuse.co/devices/tinyCurrent-precision-low-Current-Measurement-Shunt-and-Amplifier-Devicehtml
 
<https://www.n-fuse.co/devices/tinyCurrent-precision-low-Current-Measurement-Shunt-and-Amplifier-Device.html>
 
 
Anyone already have one of these?  Anyone else interested in getting or 
building one?
Other options/ideas?
 
---> Paul
 
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