Figure 3 – Transmitter (TX) Output Offset
Figure 5 – Typical 1553 Bus Connections
LAST BIT
Transformer Coupled Stub
70Ω
Magnified View
OUTPUT OFFSET
ACT 4487
*
*
TX DATA OUT
2:1
3
2
7
C
1:1.4 52.5Ω
0 Volts
OUTPUT OFFSET
A
TX DATA OUT
2.5 µsec
1
5
T1553-2
Zoi
V
CM
52.5Ω
RX DATA IN
RX DATA IN
*
Offset measured at point A in Figure 5
Direct Coupled Stub
Figure 4 – Hybrid Power Dissipation vs. Duty Cycle
(Total hybrid with one channel transmitting
and the other not powered – 100% Duty Cycle)
3600
3200
2.97W
POWER DISSIPATION
MILLIWATTS
2800
2400
2000
1600
1200
800
400
0
0
10
20
30
40
50
60
Typical Hybrid
Dissipation
Typical Hybrid Input Power
1.87W
RX DATA IN
TX DATA OUT
RX DATA IN
1
4
T1553-2
52.5Ω
Zoi
70Ω
ACT 4487
TX DATA OUT
1.4:1
3
8
2
B
52.5Ω
A
0.270
Transformer Model use Technitrol Part# 1553-2
or equivalent
70
80
90 100
DUTY CYCLE – PERCENT
Note: Vcc= +15V, V
EE
= -15V, V
L
= +5V, Transformer ratio 1.4:1,
V
BUS
(point A) at 7.5VP-P.
Configurations and Ordering Information
ACT
Model # / Ordering Part #
ACT 4487-D
ACT 4487-DI
ACT 4487-DF
ACT 4487-DFI
Specifications subject to change without notice.
Aeroflex Circuit Technology
Case
Style
DIP
DIP
FP
FP
DESC
Number
5962-8757910X_
5962-TBA
5962-8757910Y_
5962-TBA
Rx Standby
Normally Low
Normally High
Normally Low
Normally High
5
SCD4487D REV B 3/10/98 Plainview NY (516) 694-6700
AEROFLEX [ AEROFLEX CIRCUIT TECHNOLOGY ]
