Sierra Wireless AirLink MP890, User Manual

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AirLink MP User Guide
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Figure 4-11: Wiring for using Pin 3 (digital output) as an electronic switch. Pin 10 is Ground.
The digital I/O ports provide open-collector output to a maximum of 500 mA.
Analog input devices
Analog input devices are those that generate a signal of varying voltage, based
on the state of an instrument or gauge. An example of an analog input device
might be a sensor that detects the vehicle’s speed.
An analog input can be connected to four of the pins on the DB15HD connector:
Pins 7, 8, 14, and 15.
Typically an analog input device should be connected between Ground (pin 10)
and the input port (Pin 7, 8, 14, or 15).
Figure 4-12: A sensor wired to Pin 7 (analog input) and Pin 10 (Ground).
The analog input ports use a 10-bit (1024-step) analog-to-digital converter over a
range from 0 to 3.45 VDC, yielding a digital step resolution of 0.0032 V.
Example: analog sensor connections
An I/O cable for an analog sensor requires a wire to one of the analog input pins
(such as #7) and one wire to the Ground pin (#10).