I tested the circuit and it works with LM317 as a power supply. I only the changed the transistor as I did not have the same one.
There are 2 capacitors on the “3V3” pin whic are “1F” and “100nF”.
If this is an answer to my remark about decoupling caps then read my remark again. The key information is that you will need these caps at every vcc pin.
In other words: Every vcc pin must be connected to 3v3 via a capacitor.
It also means every GND pin must be connected to ground. (The best option is an uninterupted ground plane on a separate layer. If this is not possible then try to have as good of a ground connection as you can.)
I did not find any valid documentation for this module. The documentation for the board itseld (Amica wifi modulel) is different from the documentation for ESP8266.
In slightly better words: Every IC Vcc pin should be connected to 3v3 with a capacitor from 3v3 to ground as close as possible to that pin. This is colloquially known as a bypass cap or decoupling cap. (I changed “must” to “should” because in slow rise-time circuits or dirty prototyping one may be able to get away without the caps. But as mentioned below it really is good practice and something one learns with experience.)
This will not show up in your data sheet for your voltage regulator chip, but it is good design practice. Usually the value is 0.1µF (or 100nF, same thing) because that is a good enough value for most situations without having to calculate it for every circuit. Often the datasheet for ICs will state the need for these bypass caps.
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NodeMCU is a module, in fact it is a module on a module. It’s open source, and there are many copies and clones with variations. A schematic for the “official” NodeMCU is here.
I would assume that the module already has decoupling caps for the CPU, and that any of the VCC/GND pins on the module can be used. But there is no good reason not to connect all of them. Be careful though, some NodeMCU versions have different pinouts. The NodeMCU module has a 3.3v regulator, so you can feed it 5V-9V.
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Thanks for the good practice tips. I have not connected them, because on the old prototypes (different project PCB) they were working fine, even with a 90W motor next to them.
Its almost impossible to find a valid documentation for this board. Its not the original, its “Amica”. Original is “ifset” or something like this. Amica are partners of the original and are officially allowed to make the module, but they are still hobyists and can not make a valid datsheet. Inside there are pretty pictures with no good specification for what they offer. Its left to guessing… Like the fact that ESP8266 has a “1V” adc, but the whole module has a “3V” adc.
I know about the voltage regulator, I am feeding it with “5V”.
Only 1 battery can not be used as a power supply, because they will charge and discharge not evenly.
On the datasheet, of course! You need to scroll past page 1, down to the section on selecting the inductor value.
Again, if you scroll past page 1 of the schematic @bobc posted you would see that there is a resistor divider on the ADC input to reduce 3.3V to 1V.
Not on any schematic we’ve seen you’re not, you don’t even a 5V regulator.
Anyway, I wish you luck but I will refrain from offering you any further advice. No offense intended but your electronics experience would seem to be minimal yet you correct everyone who tries to help you.
This post has been dragging along for quite some time now.
I sort of lost interest after OP posted the manual of his battery charger, with a clear picture of 2 batteries in series with 2 chargers and then asked if he can put 2 batteries in series.
In this “pretty advanced” forum I’ve also found a “mute” button.
I wonder how that works.
Bye.
I do not take it personal. I have used the Vin pin with the 5V regulator even if I have not posted it.
I know about the voltage divider, what I meant is that the documentation for this is very hard to find if it even exists.
I will check the datasheet again, but I could not find this last time.
Yes this has been draggin for too long, I think that to some extent you did not understand what I wanted to say and achieve, but no matter, its time to end it.
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