Version 1.1 (released 14 April 2021)
http://razorbillinstruments.com
Page 19 of 40
M
P
2
4
0
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H
IG
H
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L
A
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IO
N
M
U
LT
IP
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R
Pin allocations
The pins are numbered according to Figure 4 and the pin
numbers are also moulded into the connector. The pin allocations
are shown below:
Pin
Function
1
Channel 1 Enable
2
Channel 3 Enable
3
NC
4
NC
5
Ground
6
Power (+5 V)
7
NC
8
NC
9
Channel 2 Enable
10
Channel 4 Enable
11
NC
12
NC
13
NC
14
NC
15
NC
Shell Ground
Enable pins
The enable pins are active high. When a channel enable pin is
driven high, the relevant relays in both the high and low bank
will be set to connect the corresponding BNC connector to the
COM BNC connector. When a channel enable pin is pulled low
or left floating, the corresponding BNC connectors will be
connected to ground.
Power supply pin
Pin 6 is intended for use with Andeen Hagerling capacitance
bridges, which have a well-regulated 5V output. The power input
is only minimally protected and can be damaged by e.g. reverse
connection or overvoltage. There is a PTC fuse, if the fuse
