Author Topic: Feedback on my Battery Monitor circuit please?  (Read 1050 times)

0 Members and 1 Guest are viewing this topic.

Offline ElectricPowerTopic starter

  • Frequent Contributor
  • **
  • Posts: 297
  • Country: no
  • I have many opinions but have no idea
    • Turer, fjas & slabberas
Feedback on my Battery Monitor circuit please?
« on: August 17, 2022, 05:09:37 am »
I want to monitor my +12V battery in my motorcycle wireless and i use Wemos D1 Mini and Blynk app for that.

Coding and connections to det Wemos D1 Mini i so not need help with, but i wan't feedback on the circuit under if there is important mistakes i have done or else.

The TP4056 module will be soldered to the PCB.

I want to power board with USB at the same time the 1 cell 18650 battery Charges.

1567696-0

1567687-1

« Last Edit: August 17, 2022, 05:14:49 am by ElectricPower »
 

Offline Mr.B

  • Supporter
  • ****
  • Posts: 1237
  • Country: nz
Re: Feedback on my Battery Monitor circuit please?
« Reply #1 on: August 17, 2022, 06:03:27 am »
The VCC of the 12V battery is shown as shorted to GND in the schematic.
This will of course result in one or more tracks turning into small balls of flying molten copper.
If you remove the short to GND it still will not work as desired.
The two series resistors are wrong and will result in the analogue input of the D1 Mini seeing the actual battery voltage, a nominal 12V.
The input of the analogue pin should be configured with a voltage divider. Calculating that divider should be very easy. I don’t know the analogue range of a D1 Mini, haven’t looked it up.
The output of the TP4056 seems to be 5V. The output of the HT7333 is 3.3V.
I don’t know how tolerant the HT7333 is of being back fed with 5V, but I would suggest it is not at all recommended.
The supply voltage of the D1 Mini appears to be 3.3V, so the TP4056 supply of 5V will not be healthy for the D1 Mini.
A 1000uF capacitor on the VBUS input to the HT7333 will have a massive inrush current that the USB supply is unlikely to handle very well.
To make the power supply electrically work you need to cut the connection between VBUS on the USB and the VIN of the regulator (HT7333).
Then, connect the output + of the TP4056 to the VIN of the regulator, not the VOUT.
Change the 1000uF cap to a much smaller value, or nothing at all depending on the output filtering of the TP4056.
I am pretty sure these little modules (TP4056) can charge and supply at the same time, but I may be wrong.
That should satisfy the electrical requirements of the regulator and the D1 mini, however the life of your 18650 battery is going to be terrible due to the TP4056 running all the time to boost the 3.7V up to 5V.
There are considerably better ways to do this.
When I get home I will try to find a design I did that is very similar using an ESP8266 as the MCU…
I approach the thinking of all of my posts using AI in the first instance. (Awkward Irregularity)
 

Offline ElectricPowerTopic starter

  • Frequent Contributor
  • **
  • Posts: 297
  • Country: no
  • I have many opinions but have no idea
    • Turer, fjas & slabberas
Re: Feedback on my Battery Monitor circuit please?
« Reply #2 on: August 17, 2022, 03:22:47 pm »
Forst of all. Thank yoy wery mutch for good feedback! :)

1. you are right. Thee VCC is cooected straight to ground. I will fix that. Thanks.

2. actually, Wemos d1 mini has an intern voltage divider with pin A0 with 220K and 100K resistor. So that part works fine. I have testet.

3. i see that with the backfeeding HT7333. I will look in to that :)

4. yes, you are right again. The 5V is going straight to 3.3V pin. Not good. Thanks.

5. yes i will change the 1000uF cap.

Thanks. I really appreciate that. I look forward to see your design :)
 

Offline ElectricPowerTopic starter

  • Frequent Contributor
  • **
  • Posts: 297
  • Country: no
  • I have many opinions but have no idea
    • Turer, fjas & slabberas
Re: Feedback on my Battery Monitor circuit please?
« Reply #3 on: August 17, 2022, 09:47:31 pm »
I have changed my schematic now and i did som adjustments.

Here i'm use an own LDO (HT7333) for battery input, and i have removed the charge board (TP4056). I just don't need it. Wemos is programmed to wake up 4 times a day, and send voltage data to my app. I can just use 3-4 AA batteries in series or and precharged 18650 etc. I don not think i have to change this battery very often.

Her is my new simplified chematic and picture of the board.

 

Offline NiHaoMike

  • Super Contributor
  • ***
  • Posts: 9012
  • Country: us
  • "Don't turn it on - Take it apart!"
    • Facebook Page
Re: Feedback on my Battery Monitor circuit please?
« Reply #4 on: August 18, 2022, 02:54:25 am »
Add pulldowns on the USB-C connector, else it won't work on some devices.
https://hackaday.com/2022/08/16/usb-c-charging-mod-brings-in-the-juice/
Cryptocurrency has taught me to love math and at the same time be baffled by it.

Cryptocurrency lesson 0: Altcoins and Bitcoin are not the same thing.
 

Offline ElectricPowerTopic starter

  • Frequent Contributor
  • **
  • Posts: 297
  • Country: no
  • I have many opinions but have no idea
    • Turer, fjas & slabberas
Re: Feedback on my Battery Monitor circuit please?
« Reply #5 on: August 18, 2022, 04:39:15 am »
I will only use standard 5V USB power supply for powering the board. Do i still need pulldown resistors?
 

Offline ElectricPowerTopic starter

  • Frequent Contributor
  • **
  • Posts: 297
  • Country: no
  • I have many opinions but have no idea
    • Turer, fjas & slabberas
Re: Feedback on my Battery Monitor circuit please?
« Reply #6 on: August 23, 2022, 08:59:02 pm »
Some modifications since last.

Some more feedback would be great :)

* Schematic_MC BATTERY CONTROLLER_2022-08-23.png (285.12 kB. 2500x2004 - viewed 31 times.)

* board_3.PNG (82.52 kB. 636x1188 - viewed 22 times.)
 

Offline NiHaoMike

  • Super Contributor
  • ***
  • Posts: 9012
  • Country: us
  • "Don't turn it on - Take it apart!"
    • Facebook Page
Re: Feedback on my Battery Monitor circuit please?
« Reply #7 on: August 24, 2022, 03:02:06 am »
I will only use standard 5V USB power supply for powering the board. Do i still need pulldown resistors?
Resistors are cheap, you'll need then to guarantee proper operation with all power supplies.
Cryptocurrency has taught me to love math and at the same time be baffled by it.

Cryptocurrency lesson 0: Altcoins and Bitcoin are not the same thing.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf