Good day,
I am working with the lighthouse deck for non-drone purposes and am therefore developing my own interface hardware.
According to the documentation, when using the external UART port (P3), the logic voltage must never exceed 3.2v.
My question is, does this apply to the other interfaces as well, such as I2C, UART1, etc?
Judging from the provided schematics, I do not see why it would be otherwise but the seed of doubt has already been planted.
I mainly ask this because I may have already ordered some PCBs and accidentally inverted the UART1 TX and RX pins meaning the voltage divider is on the wrong pin, requiring a reflash of the deck's bootloader to fix...
Best regards,
Alex
[SOLVED] Voltage considerations when interfacing with 3rd party hardware
-
- Beginner
- Posts: 2
- Joined: Wed Apr 13, 2022 5:54 pm
[SOLVED] Voltage considerations when interfacing with 3rd party hardware
Last edited by highvis_supply on Thu Apr 14, 2022 5:19 pm, edited 1 time in total.
PhD Candidate
Department of Engineering
The University of Tokyo
Department of Engineering
The University of Tokyo
Re: Voltage considerations when interfacing with 3rd party hardware
The FPGA on the lighthouse deck is a bit sensitive and we have managed to break some due to just applying 3.3V. So injecting any voltage above 3.2V on any pin seams dangerous.
A possible solution would be to exchange the 3.0V regulator (U2, TLV70230) to a 3.3V one on the lighthouse deck if you are using 3.3V on you interfacing board.
A possible solution would be to exchange the 3.0V regulator (U2, TLV70230) to a 3.3V one on the lighthouse deck if you are using 3.3V on you interfacing board.
-
- Beginner
- Posts: 2
- Joined: Wed Apr 13, 2022 5:54 pm
Re: Voltage considerations when interfacing with 3rd party hardware
Thank you for your reply,
It seems the ideal in my case would be to avoid any hardware modifications and flash a new bootloader with the two pins inverted to ensure no overvoltage issues, rather than attempt to source regulators for a reasonable price...
I do find it bizarre that the FPGA would fail so easily considering that 3.3v falls well into the recommended operating conditions.
It seems the ideal in my case would be to avoid any hardware modifications and flash a new bootloader with the two pins inverted to ensure no overvoltage issues, rather than attempt to source regulators for a reasonable price...
I do find it bizarre that the FPGA would fail so easily considering that 3.3v falls well into the recommended operating conditions.
- VCCIO1,2,3 - min 1.71v - max 3.46v
PhD Candidate
Department of Engineering
The University of Tokyo
Department of Engineering
The University of Tokyo