User's Manual

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APPENDIX (A)
A.1 IEC 61162-2 Data Interface
The CAMINO-701 Class A AIS Transponder provides 2 types of IEC 61162-2 data interfaces for user applications.
The first interface type includes 3 input-only sensor data ports and the second interface type includes 4
bidirectional input/output ports. Data port for each interface type will be described in the following section
below.
A.1.1 Sensor Data Input Ports
The schematic of input-only sensor data port is shown in Figure A1. The schematic includes a standard V.11
transceiver IC (Texas Instruments SN65176B) combined with high speed photocoupler which are used as the
main components to receive external data. The transceiver IC is isolated from external input. To avoid signal
reflection, the transceiver IC has an optional built-in 120Ω loop termination, which is selectable by the dip-
switch on the junction box and the switch should be set to on position when connecting external data source
with long cable. All sensor data-input ports are isolated from one another and are also isolated from internal
power supply. The input impedance on A/B wires is greater than 12 KΩ and the levels on the A/B wires are
defined in the following:
 Logic low input: A-B < -0.2V
 Logic high input: A-B > +0.2V
1K
3V3
System Ground
Isolated Ground
1K
A
B
TGND TGND
120
A
B
TGND
Junction Box
Cable
Rx
Isolated
Main Unit
To
system
Data
Input
V5T
Figure A1 Schematic of sensor data input port.