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Topic: Small bus Pirate clone (Read 7437 times) previous topic - next topic

Small bus Pirate clone

Hey,

I've been quite happy with my sparkfun bus pirate. After seeing this project http://http://dangerousprototypes.com/forum/viewtopic.php?f=56&t=1916 I decided I would attempt to redesign the bus pirate to be as small as possible, whilst still maintaining full functionality.

My final design turned out to be about %50 smaller than the sparkfun version. Some alterations were needed, these involved replacing the FTDI IC with a QFN package PIC18F14k50. The Main PIC is also using a QFN version. This could be made smaller by using combined LEDs (RGB / RG /etc), resistor arrays, smaller header, micro usb socket. I'm more than happy to provide the eagle/gerber files if anyone really wants them, but half the fun was making the layout.

If anyone has a smaller design I'd love to see it.
-Greeeg

Re: Small bus Pirate clone

Reply #1
Wow! Aces! Would you be willing to release the files to include in the Bus Pirate SVN?
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Re: Small bus Pirate clone

Reply #2
this is awsome, i want one!

Re: Small bus Pirate clone

Reply #3
[quote author="ian"]Wow! Aces! Would you be willing to release the files to include in the Bus Pirate SVN?[/quote]

I haven't worked with PICs for along time, so it'll take me awhile to get the USB-> serial code sorted. But once that has been set up, sure thing.

Re: Small bus Pirate clone

Reply #4
[quote author="Greeeg"]

I haven't worked with PICs for along time, so it'll take me awhile to get the USB-> serial code sorted. But once that has been set up, sure thing.[/quote]

i have worked with the qfn ft232 before, i believe it is an excellent replacement for the soic, it would fit within the same footprint

Re: Small bus Pirate clone

Reply #5
Here are the eagle PCB files. Please note these are still somewhat untested.

Re: Small bus Pirate clone

Reply #6
Very nice looking.  Nothing like a $/sq-in production cost to motivate a reduced form factor, is there?  Was it tough to solder the QFN parts?  I've been a bit shy of them.

Re: Small bus Pirate clone

Reply #7
[quote author="schazamp"]Very nice looking.  Nothing like a $/sq-in production cost to motivate a reduced form factor, is there?  Was it tough to solder the QFN parts?  I've been a bit shy of them.[/quote]

i know it is not my project, but 0.5mm pitch qfn parts can be done by hand, it does take a steady hand, and magnification. liquid flux helps too.

Re: Small bus Pirate clone

Reply #8
[quote author="sqkybeaver"][quote author="schazamp"]Very nice looking. Nothing like a $/sq-in production cost to motivate a reduced form factor, is there? Was it tough to solder the QFN parts? I've been a bit shy of them.[/quote]

i know it is not my project, but 0.5mm pitch qfn parts can be done by hand, it does take a steady hand, and magnification. liquid flux helps too.[/quote]

Don't forget the right tools :) finetipped iron and hot-air would help a lot.

I think also the footprint helps a lot. I've just send boards with through-hole a solderpad for test to manufacturing.. I hope the qfn can be soldered by hand, only using  a solderingiron and flux. I will post the findings on the blog.

Re: Small bus Pirate clone

Reply #9
the pads should extend about 2mm past the side of the package, i use a chisel tip and pre-flux both the bottom of the chip and the board.

Re: Small bus Pirate clone

Reply #10
I soldered these by tinning the pads on the IC's then the pads on the board. Removing almost all the bulk of the solder on the board using flux and a wick. Adding some no clean flux. Then careful positioning of the IC and a quick treatment of hot air usually does the trick. I also use hot air and flux to neaten up resistor/capacitor alignment.

Re: Small bus Pirate clone

Reply #11
I've programmed the 14k50 with Microchips CDC demo, Managed to use the "Low cost development board" build configuration with no moderation. only 2 macros for the LEDs needed to be adjusted. The next step will be to use the open source USB stack. :D

Just ran the self test, and got no errors :D
So this is now a fully functional Bus Pirate, small enough to carry around with you anywhere.

(I have managed to compile the open source CDC test and get it to run. But haven't set up the USART functions yet.)

 

Re: Small bus Pirate clone

Reply #12
Nice work, thanks for the update.

Thank you also for the files, I added them to the Bus Pirate SVN here:
http://code.google.com/p/the-bus-pirate ... dware%2Fv3
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