ACT4418 Molded Dual Variable Amplitude Transceivers
for MACAIR A3818, A5690, A5232, A4905
& MIL-STD-1553
Features
鈥?ACT4418 Dual Transceivers meets
MIL-STD-1553A&B, Macair A3818,
A4905, A5232 and A5690 Specs
鈥?鹵12 Volt Power Supply Operation
鈥?Voltage source output for higher bus
drive power
鈥?Molded Plug-in package
鈥?Monolithic construction using linear
ASICs
鈥?Variable TX Amplitude
鈥?Processed and Screened to Mil-STD-883
Specs for Industrial temperature range
www.aeroflex.com/act1.htm
CIRCUIT TECHNOLOGY
General Description
The Aeroflex Circuit Technology
ACT4418D is a new generation
monolithic transceivers which provide
full compliance with Macair and MIL-
STD-1553 data bus requirements
while providing variable amplitude
control.
The ACT4418D performs the front-
end analog function of inputting and
outputting data through a transformer
to a MIL-STD-1553 or Macair data
bus. The ACT4418D can be consid-
ered a "Universal" Transceiver in that
it is compatible with MIL-STD-1553A,
B, Macair A-3818, A-4905, A-5232
and A-5690.
Design of these transceivers
reflects particular attention to active
filter performance.This results in low
bit and word error rate with superior
waveform purity and minimal zero
crossover distortion. The ACT4418D
active filter design has additional high
frequency roll-off to provide the
required Macair low harmonic
distortion
waveform
without
increasing
the
pulse
delay
characteristics significantly.
Efficient transmitter electrical and
thermal design provides low internal
power dissipation and heat rise at
high and well as low duty cycles.
Variable amplitude is adjusted with
0鈥?0 Vdc on the control pin.
One Channel
TX DATA OUT
TX DATA IN
TX DATA IN
V+
TX INHIBIT
AMP CONTROL
RX DATA OUT
DRIVER
SHAPING
OUTPUT
STAGE
TX DATA OUT
COMP.
+5V
-12V
GROUND
RX DATA IN
RX DATA IN
+12V
STROBE
INPUT
AMP
V-
ACTIVE
FILTER
COMP.
RX DATA OUT
Transmitter:
The Transmitter section accepts bi-
phase TTL data at the input and
when coupled to the data bus with a
1:1 transformer, isolated on the data
bus side with two 52.5 Ohm fault iso-
lation resistors, and loaded by two 70
Block Diagram (without Transformer)
eroflex Circuit T
echnology
鈥?Data Bus Modules For The Future 漏 SCD4418D REV A 9/24/97
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