Airbus Iridium SATCOM System
165E5733-00
L-3 Aviation Recorders Proprietary
Issue, Rev. 02
21 January 2014
Page
31
3.5.7 Discrete
Outputs
Each discrete output transitions between an ‘Open Circuit’ (high-impedance-to-ground) and a ‘Closed
Circuit’ (low-impedance-to-ground) state to indicate a change in output logic.
Quantity: 8
Configurable
‘Open Circuit’ Impedance:
>100 k
Ω
‘Open Circuit’ Voltage (Max.):
36 VDC
‘Closed Circuit’ Current Limit (Min.):
500 mA
Voltage Across ‘Closed Circuit’:
<1.25 V
3.5.7.1 Configurable Outputs
The Discrete Outputs use ‘Open-Closed’ signal levels, where the output is either high-impedance to
ground (Open) or low-impedance to ground (Closed). Each configurable discrete output is individually
software-configurable for the following:
Logic Assignment: Active Low (Closed) or Active High (Open)
Function: Selected from list.
Refer to §6.11 for additional information on use of configurable outputs.
3.5.8 Two-Wire
Phone
Quantity: 2
Format:
Standard 2-Wire Tip and Ring Loop
Loop Battery:
48 ±4 VDC
Ring Signal:
20 Hz ±10%, 90 ±10 VAC RMS
Hook Flash:
<700 ms
Load Impedance (Nom.):
600
Ω
Polarity Sensitivity:
None
Audio Band Pass:
300 – 3400 Hz
3.5.9 Microphone
Input
Quantity: 1
Format:
Standard DO-214 Microphone Input
Dynamic Range:
20 mV to 1.5 V RMS
Input Impedance:
150
Ω
± 20%
Mic. Bias (No Load):
16 ± 0.5 V
Mic. Bias Ripple:
<1 mV RMS in the 300 – 3400 Hz band
