TP4056 charger problem

Hello,

I know this is a KiCad forum and not an electronics support forum but maybe someone can help me out here.

I created the attached schematic and the attached PCB design. I ordered the PCB, soldered it but the battery is not charging. The blue LED is on and the red LED is shining just a little bit. The output voltage from the TP4056 is nearly 4.2 V. So this all seems to be ok and is similar to the behavior of the boards I bought.

The only difference to the most TP4056 boards is, that I used this MOSFET IC:
https://www.lcsc.com/product-detail/MOSFETs_HL-8205_C7499847.html
instead of this one:
https://www.lcsc.com/product-detail/MOSFETs_TECH-PUBLIC-8205A_C7419210.html

but this shouldn’t be a problem when wiring everything up in accordance to the data sheet, right?

Thank’s for your help

Check voltage on the gates of Q1, is the protection IC allowing the charge? If not try shorting it’s CS pin to ground temporarily to reset it.

Nicely drawn schematic. Just a few too many junction dots; the only real criticism from me. I’d also have re-drawn the TP4056 so pin 1 was under Pin 2; then my Gnd. would point down, but that is only my OCD shining through.

Enough of the review :slightly_smiling_face:

I see one problem so far.
R6 is supposed to connect to Batt -ve not Gnd, according to the suggested circuit in the Data Sheet.

Schematic seems OK except for that one problem.
I’ll assume DRC gave the OK for the PCB.

Which probably is seen as an overcharged battery

The junction dot on the GND symbols mean that you have stray wires under the symbols that need cleaning up, although they do no harm.

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Nit picking realy but why does pin 7 of U1 have to drop down a layer to connect to D1 :thinking:
:mouse:

Thank you.

As you can see here:
https://www.best-microcontroller-projects.com/tp4056.html
R6 goes to GND.

The wiring is correct as long as I use the 8205A in the TSSOP-8 housing.
But I decided to use the IC in the SOP-23 housing and so I accidentally mixed up the MOSFET gates.
I changed the wiring and now the battery is charging and the red LED is on.

I changed the PCB design and go now for the TSSOP-8 chip because the Rds-on is lower and the Vgs(th) as well.