ijustpostwhenimhi
953
24
3
Thanks Proto-Advantage https://www.proto-advantage.com
Today I got the 2 main chips soldered to their adapter boards from Proto-Advantage. One is a "gold standard" PLX chip, but I'll also be trialing a smaller and cheaper option from Diodes Inc. I know the Pi5 to work well with PLX chips, but I have no compatibility info for the DI chip, so I wanted to try it out.
For those wondering about the placement, they only sell so many different sizes and if they don't have the exact size, they''ll use the next size up that has the same pin pitch.
Preroll container for scale
Antininny
upvoting primarily for preroll container
bladderinfection
Upvoting because you made me go back and read the title of an excellent Metallica song.
Antininny
I interviewed with Metallica in 2018.
weedeewee
I'm curious how well the PCIe signals will behave given your prototype method.
ijustpostwhenimhi
I'm using direct solder to board PCIe twinax cables for the actual breadboard "traces". My only concern is the distance between the pad and the chip on the adapter where there isn't matched lengths and impedance. I'm hoping the short distance will minimize any ill effects. I may try to ground shield the adapter traces as much as I can. I'll also have full access to the equalization and gain settings of the switch, so I may be able to compensate if needed.
weedeewee
🤞
ijustpostwhenimhi
https://www.mouser.com/ProductDetail/538-100068-0080 cables I'll be using for the PCIe and clock signals. 85 ohm is PCIe spec
SPiRALFACToR
this.
the intra and inter pair skew is going to be wild.
ijustpostwhenimhi
It's not going to be ideal, but at gen3 speeds I should be able to keep skew in spec. The PLX chip also has skew correction and delay tuning available via configurable registers