Am Di 4. März 2008 schrieben Sie, Andy Green: > I just woke up -- and talk about GTA02 only -- but JACK_INSERT at least > has 10K series resistor and a 1K to 0V I believe from the audio amp > side, so this should be no problems. HOLD I would have to check.
Hold has 10k. JACK-INS even has a suppressor diode D4402 on GTA01, sorry here. > > Debug connector is probably OK since it is normally NC and does not come > out of the case. Ok. So special care should be taken on how to connect it, in case. First connect USB? > > BATTEMP IIRC also has a series resistor as part of the network and one > to 0V so it should be OK. No series R for GTA01! But not a CPU-IO, just 50606, which i assume is a "tough" one. > Touchscreen is a good point, although again I think it is inherently a > high impedence path. For GTA01: U6003 U6004 have no protection (maybe built in?) ******** GTA02: direct connect to CPU! No ESD protection! *********** > GPS I will look at later, I guess there is some matching network at > least between it and the chip. Nope, nothing in the path there, just phantom, which is L and so is useless. ******** GTA02: the same. No ESD protection! **************** Make GND before signal connector might help, assuming external dev is low imp > The impedence matters because it affects what is actually seen by the > protection diodes in the chips it connects to. It is a lot easier for > them to shrug off an ESD event via 10K than directly. ACK. jOERG
