Keysight Technologies Infiniium 90000A Series, Service Manual

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66 90000 A-Series Service Guide
4
Troubleshooting
Checking the Display Board Video Signals
The video signals are checked on the 32-pin connector J2 on the display board
MP12. You can use an oscilloscope with a bandwidth of at least 100 MHz to verify
the signals. Even-numbered pins are closest to the PC board. If the signals are not
present, suspect the display card. If the signals are present and the backlights are
on, suspect the flat-panel display as the problem. Note that CLK, A0, A1, A2, and
A3 are Low Voltage Differential Signals (LVDS).
Video Signals
Pin Number Signal Pin Number Signal
1 NC 26 NC
2 CLK- (LVDS pair) 27 NC
3 CLK+ 28 NC
4 GROUND 29 NC
5 A3- (LVDS pair) 30 NC
6 A3+ 31 NC
7 GROUND 32 NC
8 A2- (LVDS pair)
9 A2+
10 GROUND
11 A1- (LVDS pair)
12 A1+
13 GROUND
14 A0- (LVDS pair)
15 A0+
16 NC
17 NC
18 NC
19 NC
20 NC
21 GROUND
22 GROUND
23 +3.3 V
24 +3.3 V
25 +3.3 V