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Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 12 Apr 2018, 00:07
by spachal
Hi, I'm asking about it just to be sure, because I don't want to destroy another board (is's not the question of money, but long delivery time ;] ..).

I have nodeMCU 1.0 V3 board - this one: https://www.aliexpress.com/item/-/32820380705.html . I can power it by microUSB connector, of course, but I'd like to use VIN/GND pins on board instead. I found some discussions about problems with this variant of board power supply, but also in seller's description there is "DC 4 ~ 9v PowerIn pin VIN" note.

As I said, maybe it's a complete stupid question, but could I use reliable 5V/2A power supply connected directly to VIN(+) and GND (-) pins?
Thanks for info! :]

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 12 Apr 2018, 05:53
by grovkillen

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 13 Apr 2018, 10:15
by spachal
Hi, thanks for info, I know this wiki page, but there is no information about powering boards directly from pins ..
I already know that I need reliable power supply (I have MW 5V/3A power supply available) and good thick cable with as lowest AWG as possible :]. I have three the same boards, one of them is spare one, so it seems that I have to experiment by myself. I the worst scenario I just order another one from supplier ..

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 13 Apr 2018, 10:44
by legalo

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 13 Apr 2018, 16:32
by toffel969
spachal wrote: 13 Apr 2018, 10:15 Hi, thanks for info, I know this wiki page, but there is no information about powering boards directly from pins ..
I already know that I need reliable power supply (I have MW 5V/3A power supply available) and good thick cable with as lowest AWG as possible :]. I have three the same boards, one of them is spare one, so it seems that I have to experiment by myself. I the worst scenario I just order another one from supplier ..
Hi thats not correct. The wiki states that you actually should use the Vin and not the USB.

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 13 Apr 2018, 16:41
by grovkillen
toffel969 wrote: 13 Apr 2018, 16:32 Hi thats not correct. The wiki states that you actually should use the Vin and not the USB.
+1

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 13 Apr 2018, 22:39
by spachal
OK, thanks all for help, board works right now, powered by power supply connected to VIN&GND pins.
Did I read that mentioned wiki page wrong, or you just edited the paragraph about board powering? :]

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 14 Apr 2018, 00:16
by grovkillen
Haha! No that's a year old text ;)

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 15 Apr 2018, 12:55
by spachal
My mistake, now is absolutely clear, thanks :]

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 17 Apr 2018, 14:50
by jme
Regardin that page http://henrysbench.capnfatz.com/henrys- ... ent-board/

The vin can support up to 20V, so we can use a 12V power supply to power the nodemcu V3 ?

Could you confirm ?

Thx

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 17 Apr 2018, 16:33
by grovkillen
I would not do that but please report back ;)

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 17 Apr 2018, 16:42
by toffel969
I suppose you can. Be aware though, that the power regulator will heat up substantially, it converts the extra voltage into heat( current stays the same). For that kind of voltage drop (12v to 3,3v) a switching power regulator is the better choice. There is one for example on the wemos D1 R2.

More reading https://www.intersil.com/en/products/po ... ators.html

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 17 Apr 2018, 20:51
by TD-er
Isn't the voltage regulator on the NodeMCU a switching one?
And I'm not sure whether the USB chip on the board will survive that high voltage.

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 17 Apr 2018, 22:09
by toffel969
TD-er wrote: 17 Apr 2018, 20:51 Isn't the voltage regulator on the NodeMCU a switching one?
And I'm not sure whether the USB chip on the board will survive that high voltage.
If I remember well, it is an ams1117 ldo, 800mA. I put a lms2596 in-between 12vdc to get to 5v.
Also I believe USB on nodemcu is protected by diode.(not sure)

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 18 Apr 2018, 00:22
by spachal
In my case, 5V works well, powered by MB102 pin output.

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 18 Apr 2018, 07:21
by papperone
as far as I can remember the VIN pin of NodeMCU is NOT protected by diode and is directly connected to VCC of USB port so I'm not sure if ti can damage or not the UART chip

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 24 Apr 2018, 23:28
by jme
hi,

i have bought a 12v power supply but to be sure, i've add a 7805 to reduce voltage to 5ven then i use the vin pin

Image

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 24 Apr 2018, 23:50
by TD-er
jme wrote: 24 Apr 2018, 23:28 hi,

i have bought a 12v power supply but to be sure, i've add a 7805 to reduce voltage to 5ven then i use the vin pin

Image
That's a linear voltage regulator.
So I guess it will get rather hot, without a heat sink.
The ESP will take about 0.4 Watt, which means the 7805 will dissipate (12-5)/5 * 0.4 = 0.56 Watt.

Re: Powering of nodeMCU V3 - can I use pins instead of microUSB?

Posted: 25 Apr 2018, 00:44
by jme
Regarding this

Image

We can go up To 2w without heat sink.