PWM Backlight control of TFT Kippah (PID 2454) using external transistor

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Vogon_Poetry
 
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PWM Backlight control of TFT Kippah (PID 2454) using external transistor

Post by Vogon_Poetry »

Hello,

I'm planning out a project that uses a RP2040 feather (PID 4884) to control 4 RBG matricies in addition to rPi Zero controlling a 5" TFT screen (PID 1680) via the TFT Kippah (PID 2454). I'd like to use an PWM pin off of the RP2040 to control the backlight of the TFT screen via a transistor, but in looking at the schematic of the TFT Kippah, it looks like the way to do this is by cutting the trace from the rPi pin 4&7 and the touch point 7 (TP7 - marked 5V). Replacing this would the modulated 5V supply from the transistor connected via the TP7.

This seems like an inelegant way to do it. Am I missing an enable pin or the like on the TFT Kippah that I could toggle a control signal to instead?
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