Rigid flex pcbs?

[steve]

I have a need to fit a printed circuit board into a small cabinet, I
basically need two sides of the board to bend at 90 degrees
(connectors are an option with seperate PCB's, but the fit is very
tight). I was thinking about rigid flex pcbs. Any experience with
them? Whats the minimum size of the flexible portion, for instance?
What are the general concerns with these hybrid boards?
Price shouldn't be a concern since the boards are very small and the
parts on them are very high price. thanks!

 

[Jamie Morken]

Hi Steve,

I have a need to fit a printed circuit board into a small cabinet, I
basically need two sides of the board to bend at 90 degrees
(connectors are an option with seperate PCB's, but the fit is very
tight). I was thinking about rigid flex pcbs. Any experience with
them? Whats the minimum size of the flexible portion, for instance?
What are the general concerns with these hybrid boards?
Price shouldn't be a concern since the boards are very small and the
parts on them are very high price. thanks!

Try soldering the boards together using pads on each board like this:
http://eagleflyer.sourceforge.net/accel_gyro 1/IMAGE003.JPG

cheers
Jamie Morken

 

[steve]

Try soldering the boards together using pads on each board like this:
http://eagleflyer.sourceforge.net/accel_gyro 1/IMAGE003.JPG

cheers
Jamie Morken

Great idea, I guess I was thinking too much! Are there different
connections on each side of the board, or are both sides soldered to
the same trace (in other words are there seperate pads on each side
with different signals or is there one big pad on the motherboard that
gets soldered to both sides of the daughter board?)

Is that board some type of navigation control for a model rocket? I
fly radio control planes, I couldn't find anything on the site that
talks about it.

 

[N. Thornton]

I have a need to fit a printed circuit board into a small cabinet, I
basically need two sides of the board to bend at 90 degrees
(connectors are an option with seperate PCB's, but the fit is very
tight). I was thinking about rigid flex pcbs. Any experience with
them? Whats the minimum size of the flexible portion, for instance?
What are the general concerns with these hybrid boards?
Price shouldn't be a concern since the boards are very small and the
parts on them are very high price. thanks!

why not use wire links? Just a row of very short wire conenctions.

One plus is you can wave solder the whole lot in one piece then snap
it along the perfs. Though if density needs to be extreme you might
not want to waste the millimetres for a snapped bit.

NT

 

[Jamie Morken]

Hi Steve,

Great idea, I guess I was thinking too much! Are there different
connections on each side of the board, or are both sides soldered to
the same trace (in other words are there seperate pads on each side
with different signals or is there one big pad on the motherboard that
gets soldered to both sides of the daughter board?)

There is one big pad on the the motherboard for each solder connection,
but you could put different connections on both sides too, I only needed
6 signals though.

Is that board some type of navigation control for a model rocket? I
fly radio control planes, I couldn't find anything on the site that
talks about it.

It is a homebuilt inertial measurement unit using the Analog Devices
adxrs gyros and adxl accelerometers and a 16bit ADC, and an atmega32
with 4MB of datalogging flash.

cheers,
Jamie

 

[budgie]

why not use wire links? Just a row of very short wire conenctions.

One plus is you can wave solder the whole lot in one piece then snap
it along the perfs.

(snip)

and (as someone posted in this group a year or so back,) that approach lends
itself to product testing before snapping. Very handy.

 

[steve]

It is a homebuilt inertial measurement unit using the Analog Devices
adxrs gyros and adxl accelerometers and a 16bit ADC, and an atmega32
with 4MB of datalogging flash.

Jamie,

Very nice homebuilt, I am wondering how did you solder the BGA device?
Oven? Or an pcb assembly shop?

steve

 

[Jamie Morken]

Hi Steve,

Jamie,

Very nice homebuilt, I am wondering how did you solder the BGA device?
Oven? Or an pcb assembly shop?

Thanks! It was my first time working with BGA, I used a toaster oven
(works better than great!)

cheers,
Jamie

 

[steve]

Thanks! It was my first time working with BGA, I used a toaster oven
(works better than great!)

cheers,
Jamie

Really, did you use the same technique as these guys?

http://www.seattlerobotics.org/encoder/200006/oven_art.htm

 

[Jamie Morken]

Hi Steve,

Really, did you use the same technique as these guys?

http://www.seattlerobotics.org/encoder/200006/oven_art.htm

I used a stencil for all but one board I had, and it was a lot more
trouble not having a stencil. It can be done either way though..

cheers,
Jamie