Figure 3 – Transmitter (TX) Output Offset
0 Volts
LAST BIT
2.5 µsec
Magnified View
* OUTPUT OFFSET
* OUTPUT OFFSET
*Offset measured at point A in Figure 5
Figure 5 – Typical 1553 Bus Connections
Transformer Coupled Stub
70Ω
ACT 4487
TX DATA OUT
2:1
37
2
C
1:1.4 52.5Ω
A
TX DATA OUT
RX DATA IN
RX DATA IN
15
T1553-2
Zoi
52.5Ω
VCM
Figure 4 – Hybrid Power Dissipation vs. Duty Cycle
(Total hybrid with one channel transmitting
and the other not powered – 100% Duty Cycle)
3600
3200
2800
2400
Typical Hybrid Input Power
2.97W
2000
1600
1.87W
1200
800
Typical Hybrid
400
0.270
Dissipation
0
0 10 20 30 40 50 60 70 80 90 100
DUTY CYCLE – PERCENT
Note: Vcc= +15V, VEE = -15V, VL= +5V, Transformer ratio 1.4:1,
VBUS (point A) at 7.5VP-P.
Direct Coupled Stub
ACT 4487
TX DATA OUT
TX DATA OUT
RX DATA IN
RX DATA IN
1.4:1
38
2
B
14
T1553-2
52.5Ω
52.5Ω
Zoi
A
70Ω
Transformer Model use Technitrol Part# 1553-2
or equivalent
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