Re: Own aduc7020 pcb design
- --- In ADuC_ARM@yahoogroups.com, "martin_schoenegg" > We use to make
longer pads so we are able to use a solder iron to
> heat the pad beside the IC. Our group made several layouts (evensimple
> single sided) without mayor problems. All hand soldered with a
> solder iron, no hot air or such specials. A few hints:side.
> Please do not connect or solder the metal surface on the bottom
> The mass of tin in the hole will easyly overheat your IC.Hi,
> Don't make wires nor vias under the chip. The metal surface is
> internally connected to GND and may give a short cirquit.
> Colophonium in alcohol is your friend for such handmade things. Use
> enough of such solution or an other flux to prevent shorts
> Good luck
thanks for all tips!
Using plain solder iron (and some wick) also. The vias and wires
under the chip are GND so a short should not cause any problem.
Rechecked and remeasured everything, the only thing I can come up
with is that I've heated the ADuCs too much/long. The hole was never
filled with tin. I'm using 280 celcius on the iron - what temp are
you guys using?
I'm thinking of redoing the PCB using a bigger board with less
constraints. Just to see if I can get the processor to kick in.
Thanks / Peter
> with is that I've heated the ADuCs too much/long. The hole wasnever
> filled with tin. I'm using 280 celcius on the iron - what temp areMy Weller Magnastat prefers 370 °C and I never had any problems with
> you guys using?
this. It may be better to solder quick and hot than too cold and
needing longer, but only as long as you use very little tin. The most
important thing may be a high quality solder tip.
BTW I prefer for prototyping the cheapest colophonium based Pb-tin
with 1mm diameter ;-)
- Answering my own question as I found the problem some long while ago - stupidly enough I'd forgot to tie the JTAG pins high. Duuuh....
Cheers / P
--- In ADuC_ARM@yahoogroups.com, "pellepl" <pellepl@...> wrote:
> anyone out there ever made a (working) pcb of their own with the
> aduc7020 LFCSP package? The same which is on the minikit.
> I've successfully done some boards for the aduc7128 and 7129 lqfp
> packages, which work smoothly. But for the 7020 the uC is more or less
> dead. The internal clock seem to be alive, but all other IOs are high-z
> on 2.7 volts.
> Anyone? I'll gladly share gerbers or eagle-files ;)
> Cheers / Peter