comparison pirelli/keypad @ 63:023d55d76b28

Pirelli PCB RE: another failed attempt at tracing the keypad connections
author Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
date Mon, 02 Dec 2013 08:55:38 +0000
parents 2bc45eb8818d
children
comparison
equal deleted inserted replaced
62:c20dedad87a0 63:023d55d76b28
6 the middle. 6 the middle.
7 7
8 Here I will use pin numbers per the main PCBA silkscreen. 8 Here I will use pin numbers per the main PCBA silkscreen.
9 9
10 Geometric centre of the footprint is at (3923,456) in steve-m's L8 scan. 10 Geometric centre of the footprint is at (3923,456) in steve-m's L8 scan.
11
12 Pin 2: *guess* may be KBC0
13
14 Pin 3: L8 trace to (4068,278), L7 damaged, guessing the middle trace in the
15 bunch of 3 found when tracing KBC0. Inner via at (4084,491). Found it on L2,
16 goes to (4107,482). Goes to Calypso ball M5, or maybe N5. N5 seems unlikely,
17 as it's a power pin, so must be M5 - but that is KBC4, which shouldn't go to
18 the main keypad.
11 19
12 Pin 8: connected to massive copper flood, almost certainly GND. 20 Pin 8: connected to massive copper flood, almost certainly GND.
13 21
14 Pin 9: connected to a copper fill that's islanded by some traces, so it may or 22 Pin 9: connected to a copper fill that's islanded by some traces, so it may or
15 may not connect the same massive fill (GND?) as pin 8. In this island there is 23 may not connect the same massive fill (GND?) as pin 8. In this island there is
22 use KBC4 and KBR1 through KBR3. Let's try tracing the KBC and KBR lines of 30 use KBC4 and KBR1 through KBR3. Let's try tracing the KBC and KBR lines of
23 interest from the Calypso. 31 interest from the Calypso.
24 32
25 Tracing KBC0, Calypso ball N4: goes to via at (4122,380). Found it on L2, goes 33 Tracing KBC0, Calypso ball N4: goes to via at (4122,380). Found it on L2, goes
26 to a larger via at (4130,444). Found it on L7, trace disappears into the edge 34 to a larger via at (4130,444). Found it on L7, trace disappears into the edge
27 grind-down damage. 35 grind-down damage. The trace disappearing into the damage is the leftmost in a
36 bunch of 3, the point at which the middle of the bunch is cut off is (4116,352).
37 A *guess* is that we may be going to connector pin 2.
38
39 Let's try tracing some signals from Iota. Let's start with PWON (ball F8).
40 L1 trace from ball seems to go to (2767,974). On L2 it goes to two vias:
41 (2730,745) and (3312,194). Both vias are inner. Following (3312,194) first.
42 Unable to find it, edge damage gets in the way again.