ESP hangs and L9110S gets very warm

[nstadigs]

Hi!

I understand if this isn't a support channel for newbies like me, but I'm desperate so I'll give it a try anyhow.

I ordered a couple of boards from jlcpcb with chips assembled. The only change I made was selecting this L9110S instead of the one in the BOM, because that one was out of stock for several months. They seemed compatible, but again, I'm new to this.

I did not have any issues soldering the through hole components and I have tested all the joints.

The issue: The L9110S runs warm and the motors are supplied constant voltage of 1.3 volts, even when there is no ESP connected to the board.

Did I select an incompatible L9110S? Do you have any troubleshooting tips :grimacing:

Thanks :pray:

PS: If you were to sell ready-made boards I'd buy two of them ;)

[nliaudat]

Which motor do you use ? Have you a 3.3V power source and a multimeter to make tests ? The only difference I see with the original chip is the max voltage supported 12V for mine and 7V for yours I mean a 10K resitor is broken or not good soldered

With the EPS not connected to the shied, are the motor running on each 8 channels ?

[nstadigs]

Which motor do you use ?

HmIP-VDMOT

Have you a 3.3V power source...

I have an HLK-5M03 soldered to the board and the backside of the board secured.

...and a multimeter to make tests ?

Sure do!

The only difference I see with the original chip is the max voltage supported 12V for mine and 7V for yours

Sounds promising, thanks

I mean a 10K resitor is broken or not good soldered

Ok.. How do I best measure this?

With the EPS not connected to the shied, are the motor running on each 8 channels ?

Yes, its running on each channel

[nliaudat]

Can you give me the following inputs (labeled at back of the board), without ESP connected ?

GND-3.3V = GND-IA (speed)= GND-IB (direction)= GND-BEMF MOT1 =

[nstadigs]

Without motor connected:

GND-3.3V = stable 3.30V GND-IA (speed)= stable 3.28V GND-IB (direction)= Moves between 2.2 and 3.3V GND-BEMF = Moves between 0.1 and 0.6 V MOT1 = Stable 1.34V

[nliaudat]

I'll do some tests this evening, but the BEMF (back electromotive force) should be 0 cause no motor is connected. That's why the L9110 module is overheating Is the ESP connected or not ? Perhaps it's a faulty SN74HC595 shift register Can you put a picture of the front and the back of your board ? I'll check the soldering

[nliaudat]

Are the L9110S chips turned correctly in the right direction ?

[nstadigs]

The esp isn't connected.

The the point on the L9110S is next to the point on the board. Lower left .

Thanks! I'll send you some pictures later

[nstadigs]

[nliaudat]

Have you jumper cables ?

Can you check the motor voltage if you link IA to GND and IB to VCC, and after that IA to VCC and IB to GND. Values should be + or - 3.3V Test only on channel 1 (they are many holes labeld VCC and GND on the board)

[nliaudat]

Some of your soldering are very bad.

All soldering must be disconnected, chrome and brilliant (not dull nor yellowed). Sorry for my bad english :(

[nliaudat]

[nstadigs]

2.2 volts and 1.7 volts

Yeah, I figured my soldering wasn't the best. But I thought it would be good enough :) I'll try to fix it to see if that fixes the problem.

Thanks again!

[nliaudat]

I've reproduced your problem inverting the L9110s module upside down. I've got the same results. The L9110s module may have burn.

I can send you 2x v1.0 prototype boards and you send me back 2 of yours to do more checks if you want. I'll send you the RJ11 connectors as they are not the same parts. In v1.0, was a mistake in BEMF resistor as it was 1ohm and ESP could not read values of 3.3v. I change it later to 12ohms and i'll fix it for you as you are my only sponsor :).