ESP32-S3-Touch-LCD-4 V3.0 dimming options

[vincentmakes]

In the schematics of the v3.0 of the ESP32-S3-Touch-LCD-4 it is mentionned that the GPIO42 is connected to FB of the AP3032 via optional resistors. However after checking physically it looks like it is actually connected to EXIO5 (same as v1 and v2).
Is that an error or is creating a PWM signal from EXIO5 the right approac to dim this screen ? Is there any plan for a v4 with this native capability?
The full brightness is just too much for a permanent display at home and it is the only screen of that size with CAN capabilities I’m looking for.

[Y1hsiaochunnn]

The current version must use resistors to switch the GPIO to control the backlight. In future versions such as V4, the backlight can be controlled by an expansion chip.

[vincentmakes]

Thanks I've tried it and it works via 60Hz PWM on EXIO5 (so the schematics of v3.0 has a typo) and using the recommended resistors (R40=0R, R36=91k). However the range of dimming is still very limited, from 0 to 100% duty cycle : do you have any option to increase the range ? For instance, the dimmest possible is still maybe 40% of initial brightness,

[Y1hsiaochunnn]

You need to adjust the resistance value of R36. You can reduce it a bit, for example to 68K, to obtain a value that best meets your requirements.

[vincentmakes]

Thanks a lot ! Issue closed and for anyone else going through this, here's my repo with the dimming feature implemented : https://github.com/vincentmakes/ComfoSense-Touch