Re: TM500/TM5000 extender project

Dave Daniel
 

I noticed that you don’t have anything to strain-relieve the wires. I’d add some holes through which cable ties could be run to capture the wires.

DaveD

On Feb 12, 2020, at 17:20, Ke-Fong Lin <anotherlin@...> wrote:

Hi everyone,

The PCB is ready! I've updated the preview and the schematics.

https://drive.google.com/file/d/14WSoPeQoIwup4532_YnxUz44PVxAYJ8T/view
https://drive.google.com/file/d/1E7RxXXPg_3-Kwd652mFbe5g-4zoBeAN_/view

In particular, I've added a small circuitry to generate the "power good signal" for the TM5000 modules.
It's basically a voltage divider from 8V to 5V, and an NPN buffer. The PWR specifies a full load (16mA) of TTL high (+5V).
A small drawback is that it always draws around 2-3mA even if not to needed (inserted in a mainframe).

Can some of you do a review of the schematic? Or give some comments or suggestions?
For those really curious, I can send the complete kicad project, just ask. Final version will be an github of course.
For a pure extender use, there is just some wiring to be done. Otherwise, I'll have to provide some sort of BOM.
I also have to write a small "documentation".

Plan is to send the PCB to fabrication (JLPCB) this week-end, after feedbacks.

Best regards,


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