72 | Keysight | Probing Solutions for Logic Analyzers - Data Sheet
Probing Solutions for 40-pin Logic Analyzers
Custom Probing (Continued)
Direct connection through
40-pin connectors
Table 9. Forty-pin connectors for fixed configuration probing.
(Requires isolation network installed on target board)
The probe cable also can be plugged
directly into the various 40-pin
connectors shown in Table 9, but proper
isolation networks must be installed
directly onto the target system board
(see Figure 9.39 for the 40-pin connector
pinout).
Keysight part number
1251-8158
1251-8831
3M part number
2540-5002
3432-6302
Connector description
40-Pin, low-profile (right-angle)
40-Pin, with long latches (straight)
40-Pin, with long latches (right-angle)
1251-8931
3432-5302
+5V (see note)
CLOCK
1
3
5
7
9
2
POWER GND
SIGNAL GND
SIGNAL GND
SIGNAL GND
4
6
8
Do not connect
D15
Discrete components can also be used for
the proper isolation network. See Figure
9.42 for an equivalent load diagram for
the isolation networks.
D14
10 SIGNAL GND
12 SIGNAL GND
14 SIGNAL GND
16 SIGNAL GND
18 SIGNAL GND
20 SIGNAL GND
22 SIGNAL GND
24 SIGNAL GND
26 SIGNAL GND
28 SIGNAL GND
30 SIGNAL GND
32 SIGNAL GND
34 SIGNAL GND
36 SIGNAL GND
38 SIGNAL GND
40 POWER GND
D13 11
D12 13
D11 15
D10 17
D9 19
D8 21
D7 23
D6 25
D5 27
D4 29
D3 31
D2 33
D1 35
D0 37
+5V 39
Note that the effective input capacitive
lead of an isolation network using discrete
components is a function of the layout
geometry and the parasitic capacitance
of the input series damping resistor.
Figure 9.39. Forty-pin connector pinout.
1. +5 V is supplied from the logic analyzer to provide power for analysis probes and demo boards.
DO NOT connect these pins to a +5 V supply in the target system!