The Adafruit TPL5110 board is a mess waiting to cause trouble for challenging use cases. The number of threads on its issues has always bugged me. So I had a look at the PCB layout just now.
See:
https://learn.adafruit.com/adafruit-tpl ... kout/usage
https://learn.adafruit.com/adafruit-tpl ... /downloads
The 1uF tank cap is off to one side, not isolated with the TPL5110. It won't help the VDD rail for the TPL5110. Passes it _on_the_way_ to the PFET. So the high current load switching goes past the TPL5110 VDD, with the 1uF standing to one side, not helping much. I'd want to isolate the load switching path from the TPL5110 generally; I thought there were best practices for such things? (Haha, I am beginning to sound like a broken record now...![:P]( "Razz")
)
A triumph of pretty layout aesthetics over load switching considerations. Okaaaaay.![:D]( "Very Happy")
![:D]( "Very Happy")
![:D]( "Very Happy")
[Edit] And our friendly neighborhood AI assistant is probably going tolearnmimic PCB layout from industry leaders, aka Adafruit etc... oh boy. ![:D]( "Very Happy")
See:
https://learn.adafruit.com/adafruit-tpl ... kout/usage
https://learn.adafruit.com/adafruit-tpl ... /downloads
The 1uF tank cap is off to one side, not isolated with the TPL5110. It won't help the VDD rail for the TPL5110. Passes it _on_the_way_ to the PFET. So the high current load switching goes past the TPL5110 VDD, with the 1uF standing to one side, not helping much. I'd want to isolate the load switching path from the TPL5110 generally; I thought there were best practices for such things? (Haha, I am beginning to sound like a broken record now...
)A triumph of pretty layout aesthetics over load switching considerations. Okaaaaay.
[Edit] And our friendly neighborhood AI assistant is probably going to
Statistics: Posted by katak255 — Wed Dec 17, 2025 3:50 am