ESP32-S3 TFT 1.9 display

simpleuser

hi

I have the ESP32-S3.
I cannot figure out how to power the device via battery. It has a JST port and another port.. Which port do i connect to in order to power the device via a Li-ion battery?
What is the connector type that i need?

This is not very clear to me from the pin diagram. can someone provide me some pointers?

Thanks

teastain

https://github.com/Xinyuan-LilyGO/T-Display-S3
and
https://github.com/Xinyuan-LilyGO/T-Display-S3/blob/main/shcematic/T_Display_S3.pdf

My LillyGO T-Display S3 came with a tiny connector with two leads, red and black. probably need a 4.2 Li-ion battery

The four pin JST port is for I2C comm.

This should be all you need!

-Terry

simpleuser

@teastain Thanks Terry

I soldered up the tiny connector with 2 leads to a small Li-ion battery (280mah 4.2v) but the unit doesn't power up..
The green light provides a brief flash when the reset button is pressed and that was it.
i also made sure that the battery was charged up.

Did you manage to get yours working with a battery? what battery did you use?

thank you for the advice!

teastain

Thanks for the reply!
Sadly all of my ten years of Arduino and ESP have been powered by USB phone chargers!
Can you measure the battery voltage during powerup?
I will try to "battery power" mine tomorrow (EDT).
-Terry

simpleuser

@teastain I was really hoping to create a low power draw device that is more portable and therefore no "external wires" wherever possible.

Yes. i multi-meter tested the battery and it reads 4.2V before i plugged it in.

i'm starting to feel that i got a lemon...

teastain

It is a bit more awkward, but you must confirm battery voltage during start up!

Your Lemon, may be the battery.

simpleuser

@teastain i did test the battery under load as well. it can indeed deliver the voltage required. did you manage to test your unit with a battery? i'd be interested to know the outcome..

Thank you for your help!

teastain

@simpleuser Mine booted up right away with 3.3V coming in the battery connector. I don't have a battery!
Also are you sure of the polarity? The connector is so small and fiddly, I double checked.
Does it run OK on USB power?
Let me know!
Terry

simpleuser

@teastain Thanks continuing to help!
Yes.. quite sure of the polarity. Red is +ve and Black is -ve. It also matches correctly to whats printed on the PCB.
i measured on loaded output of the battery again and confirm its 4.2V at least.
Connecting the battery and pressing reset only causes a brief green flash.

Powering via the USB-C port has no issues. That works fine.

Is there any other way i can power the board? through some direct pins maybe?

Curious, can the board be connected to the the Li-ion battery and be connected to the USB at the same time? Will the board auto switch the power supply?

teastain

@simpleuser Unfortunately I'm out of ideas!!!
I have added T_Display_S3shematic.PDF to my LilyGO T-Display S3 GitHub repository, which is here:
https://github.com/teastainGit/LillyGO-T-display-S3-setup-and-examples
It looks like the bat connector circuit has no reverse polarity protection diode, which is silly, considering how sophisticated and complex the rest of the circuit is designed. In that case a simple one-time reversed battery leads would ruin the bat charging but not the overall functionality.
Let me know if I can be of further help, I am a retired Industrial Robot Interface designer, with time on my hands!

teastain

[EDIT] and...yes, both can be connected and a mosfet will switch between the two, it looks like the LilyGO has an on-board charger. If it will not boot with BOTH USB and Battery connected, then yes, the battery interface is toast.
-Terry

simpleuser

@teastain Thanks for checking and confirming. If the Lilygo indeed has an onboard Li-ion charger, then i highly suspect my battery interface is toast. I have not at any point reversed the polarity.

No problem i guess, i just have to change the design of my project to leverage an externally connected USB-C circuit. not ideal as the project isn't "independent" but until i get another unit, it'll have to do.

Good to know that its supposed to have an on-board charger and can take a li-ion battery though!

Thanks lots!

teastain

How about an external battery connected through the USB connector ?
Cut the end off of a C type USB cable locate the pos(+ve) and neg (-ve) conductors inside, attach your 4.2v li-ion to the cable and plug the cable into the USB C port on the LilyGO.

simpleuser

@teastain that can work... but i guess its going to look big and not as sleek anyway, might as well save myself the trouble.

nah.. thats ok.
maybe for the next project.. hahaha

teastain

Well, I did not think to ask you if you have the LCD ON commands in your sketch:

#define LCDpin 15 (before setup)
and
void setup() {
pinMode(LCDpin, OUTPUT); //triggers the LCD backlight
digitalWrite(LCDpin, HIGH);

My LilyGO T-Display S3 will not turn on the backlight reliably, until I spotted the
LCD_Power_ On 15 pin on the official schematic. This works a charm.
Also YouTuber Volos says that he has trouble getting several types of batteries to work with his.
Hope this helps, Terry

Check out my GitHub repo.

simpleuser

@teastain Thank you! this is insightful. Really appreciated. i'd have to look into it when i have the time... perhaps the type of battery? i don't know. but at this point.. USB-C it is.. hahahah