eroflex Circuit T
echnology
Data Bus Modules For The Future SCD4458 REV A 1/29/98
CIRCUIT TECHNOLOGY
www.aeroflex.com/act1.htm
Features
Single 5 Volt Supply Operation
Low Power Dissipation
Small Size & Light Weight
Dual Transceivers Save Space & Cost
Outstanding MIL-STD-1553 performance
Processed and Screened to Mil-STD-883 Specs
Radiation Hard Dielectric Isolation Monolithic construction
for Severe Environments
Superior High Frequency Line Transient and Input Ripple
Rejection
Input and Output TTL Compatible Design
DESC SMD# 5962-92061
General Description:
The Aeroflex Circuit Technology
ACT4458 / 4464 series are next
generation monolithic transceiver
designs which provides full
compliance with MIL-STD-1553A/B
and 1760 requirements in the
smallest packages with low power
consumption and single power supply
operation.
The ACT4458 / 4464 series
performs the front-end analog
function of inputting and outputting
data through a transformer to the
MIL-STD-1553 data bus.
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. Efficient
transmitter electrical and thermal
design provides low internal power
dissipation and heat rise at high as
well as low duty cycles.
Each channel of the dual
transceiver is completely separate
from the other and fully independent.
This includes power leads as well as
signal lines. Hence, each channel
may be connected to a different data
bus with no interaction.
Transmitter:
The Transmitter section accepts
bi-phase TTL data at the input and
when coupled to the data bus with a
1:2.5 ratio transformer, isolated on
the data bus side with two 52.5 Ohm
fault isolation resistors, and loaded by
Block Diagram (without Transformer)
ACTIVE
OUTPUT
STAGE
COMP.
COMP.
REFERENCE
ACTIVE
FILTER
INPUT
AMPLIFIER
DRIVER
TX DATA IN
TX DATA IN
TX INHIBIT
+5 V
RX DATA IN
RX DATA IN
STROBE
TX DATA OUT
TX DATA OUT
RX DATA OUT
RX DATA OUT
FILTER
+5V RTN
ACT 4458 / 4464
SINGLE SUPPLY TRANSCEIVERS
FOR MIL-STD-1553/1760
ACT 4458FP
Actual Size
Case Style
Aeroflex Circuit Technology
SCD4458 REV A 1/29/98 Plainview NY (516) 694-6700
2
two 70 Ohm terminations, the data
bus signal is typically 7.5 volts P-P
at A-A' (See Figure 5). When both
DATA and DATA inputs are held low
or high, the transmitter output
becomes a high impedance and is
"removed" from the line. In addition,
an overriding "INHIBIT input
provides for the removal of the
transmitter output from the line. A
logic "1" applied to the "INHIBIT"
takes priority over the condition of
the data inputs and disables the
transmitter. (See Transmitter Logic
Waveform, Figure 1.) The
Transmitter may be safely operated
for an indefinite period with the bus
(point A-A') short circuited at 100%
duty cycle.
Receiver:
The Receiver section accepts
bi-phase differential data at the input
and produces two TTL signals at the
output. The outputs are DATA and
DATA, and represent positive and
negative excursions of the input
beyond a pre-determined
threshold.(See Receiver Logic
Waveform. Figure 2.)
The pre-set internal thresholds will
detect data bus signals exceeding
1.20 Volts P-P and reject signals
less than 0.6 volts P-P when used
with a transformer. (See Figure 5
for transformer data and typical
connection.)
A low level at the Strobe input
inhibits the DATA and DATA
outputs. If unused, a 2K pull-up to
+5 Volts is recommended
DATA IN
DATA IN
INHIBIT
LINE TO LINE
OUTPUT
Note: DATA and DATA inputs must be complementary waveforms or 50% duty cycle average, with no delays between them,
and must be in the same state during off times (both high or low).
Figure 1 -- Transmitter Logic Waveforms Idealized
*
Figure 2 -- Receiver Logic Waveforms Idealized
*
Note overlap
LINE TO LINE
INPUT
DATA OUT
DATA OUT
STROBE
* See Figure 8 For Actual Waveforms
Aeroflex Circuit Technology
SCD4458 REV A 1/29/98 Plainview NY (516) 694-6700
3
Note 1. Power on or off, measured from 75KHz to 1MHz at point A-A' and transformer self impedance of 3K
minimum
Absolute Maximum Ratings
Operating case temperature
-55C to +125C
Storage case temperature
-65C to +150C
Power supply voltage
-0.3 V to +7.0 V
Logic input voltage
-0.3 V to +5.5 V
Receiver differential input
10 V
Receiver input voltage (common mode)
5 V
Driver peak output current
600 mA
Total package power dissipation over the full operating
case temperature rise
2 Watts
Maximum junction to case temperature
10C
Thermal resistance junction to case
5C/W
Electrical Characteristics -- Driver Section
Input Characteristics, TX DATA in or TX DATA in (Notes 2 & 3 apply)
Parameter
Condition
Symbol
Min
Typ
Max
Unit
"0" Input Current
V
IN
= 0.4 V
I
ILD
-0.2
-0.4
mA
"1" Input Current
V
IN
= 2.7 V
I
IHD
1
40
A
"0" Input Voltage
V
ILD
0.7
V
"1" Input Voltage
V
IHD
2.0
V
Inhibit Characteristics
"0" Input Current
V
IN
=0.4V
I
ILI
-0.2
-0.4
mA
"1" Input Current
V
IN
=2.7V
I
IHI
1.0
40
A
"0" Input Voltage
V
ILI
0.7
V
"1" Input Voltage
V
IHI
2.0
V
Delay from TX inhibit, (0
1) to inhibited output
t
DXOFF
250
350
nS
Delay from TX inhibit, (1
0) to active output
t
DXON
150
250
nS
Differential output noise, inhibit mode
V
NOI
2
10
mV
P-P
Differential output impedance (inhibited)
Note 1
Z
OI
2K
Output Characteristics
Differential output level
R
L
=35
V
O
6
7.5
9
V
P-P
Rise and fall times(10% to 90% of P-P output)
t
r
100
200
300
nS
Output offset at point A-A' on Figure 5, 2.5S
after midpoint crossing of the parity bit of the
last word of a 660S message
R
L
=35
V
OS
90
mV peak
Delay from 50% point of TX DATA or TX DATA
input to zero crossing of differential signal
t
DTX
120
250
nS
(Note: Normal operation conditions require one transceiver on and the
other off.)
Aeroflex Circuit Technology
SCD4458 REV A 1/29/98 Plainview NY (516) 694-6700
4
Note 2: V
cc
= 5 Volts 0.1 V, bypassed by 2.2 F (Tantalum recommended) Capacitor minimum. All measurements &
specifications apply over the temperature range of -55C to +125C (case temperature) unless otherwise
specified.
Note 3: When measured at point A-A' with 10 Volt peak, line to ground, DC to 2MHz
Note 4: Typical power is measured with V
bus
at point A-A' = 7.5 V
P-P
Electrical Characteristics -- Receiver Section
Parameter
Condition
Symbol
Min
Typ
Max
Unit
Differential Receiver Input Voltage Range
(See Figure 5, point PP')
TXFMR
2.12:1
V
IDR
14
20
V
P-P
Common Mode Rejection Ratio (Note 3)
CMRR
45
dB
Strobe Characteristics (Logic "O" Inhibits Output)
"0" Input Current
V
S
=0.4 V
I
IL
-0.2
-0.4
mA
"1" Input Current
V
S
=2.7V
I
IH
1
+40
A
"0" Input Voltage
V
IL
0.7
V
"1" Input Voltage
V
IH
2.0
V
Strobe Delay (Turn-on or Turn-off)
t
SD
50
100
nS
Threshold Characteristics (Sinewave Input)
Input Threshold Voltage (referred to the bus)
100KHz1MHz
V
TH
0.60
0.82
1.10
V
P-P
Output Characteristics RX DATA and RX DATA
"1" State
I
OH
= -0.4 mA
V
OH
2.5
3.7
V
"0" State
I
OL
= -4.0 mA
V
OL
0.35
0.5
V
Delay, (average) from Differential Input Zero
Crossings to RX DATA and RX DATA Output
50% points
t
DRX
340
500
nS
Power Data
Power Supply Currents Per Channel
Transmitter Standby
Note 4
I
CC
18
30
mA
25% duty cycle
150
175
50% duty cycle
300
350
100% duty cycle
600
700
Power Supply Voltage
Operating Power Supply Voltage Range
V
CC
+4.75
+5.00
+5.50
V
Aeroflex Circuit Technology
SCD4458 REV A 1/29/98 Plainview NY (516) 694-6700
5
Figure 3 Transmitter (TX) Output Wave form
Figure 4 Transmitter (TX) Output offset
Figure 5 Typical direct transformer connection
Figure 6 Power Dissipation vs. Duty Cycle
0 10 20 30 40 50 60 70 80 90 100
1600
1400
1200
1000
800
600
400
200
0
DUTY CYCLE PERCENT
P
O
W
E
R
D
I
S
S
I
P
A
T
I
O
N
M
I
L
L
I
W
A
T
T
S
6V P-P MIN
9V P-P MAX
90%
10%
t
r
*
t
f
*
*
Rise and fall times measured at point A-A' in Figure 5
0 Volts
OUTPUT OFFSET
*
OUTPUT OFFSET
*
LAST BIT
2.5 sec
*
Offset measured at point A-A' in Figure 5
N1:N2
A
A'
B'
B
TX DATA OUT
TX DATA OUT
RX DATA IN
RX DATA IN
70
70
52.5
52.5
Center
Tap
Transformer turns ratios:
N1:N2 = 1:2.5
N1:N3 = 1:1.77
Use Technitrol 1553-45 or equivalent
N1:N3 for
Stub
Coupling
0 volts
Magnified View
(Total hybrid with one channel transmitting
and the other not powered)
Note:Vcc=5 Volts,Transformer ratio 1:2.5, V
bus
(pt A-A') at 7.5 Volts P-P
P
P'
1800
2000
Maximum
Typical
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