June 15, 2013
Good stuff! Thanks. I was worried I’d have to use a 0.6mm thick PCB.
Hi again Shawn, just wondering about something on your board. I’m done with my design, but wondered what steps you had taken to ensure 50 Ohm impedance on the RF trace? TI recommends doing microstrip calculations. Your trace is 48 mils wide, which for 1Oz FR4 results in ~0.7mm thickness. I am trying to find the right compromise; a 0.8 mm thick board gives me a 56mil trace!
In short, what thickness is your board (and weight?) and how critical, as far as you know, is getting the impedance spot on?
Thanks in advance!
Thanks Shawn, I’ll consider those, but I want to make sure I have a working protoype before I outsource boards. You’ve been very helpful, I appreciate it!
Ah, I assume you are referring to this: “For best results, the RF trace ground layer must be the ground layer immediately below the RF trace. The ground layer must be solid.”
Hmmm, not looking forward to creating home-made vias…
Thanks for the help!
I see the 74HC4050 as a level shifter; I am wondering about the 74AHC1G125 between the CC3000 SPI out and the uC MISO ? Is this in case there is more than one SPI slave?
While I’m here, also wondering about the use of two ground planes? I am thinking about building my own single-sided CC3000 board, and wonder if I can get away without stitching around the antenna area.
wondering why you chose to add the 74125 in your design?
No public wish lists :(
Forgot your password?
No account? Register one!