HI-1575
Point
“AT”
HI -1575 TRANSMITTER
52.5 W
(.75 Zo)
1:2.5
1:1.4
BUSA/B
35 W (.5 Zo)
BUSA/B
52.5 W
(.75 Zo)
Isolation
Transformer
Coupling
Transformer
Point
“AT”
HI-1575 RECEIVER
52.5 W
(.75 Zo)
1.4:1
2.5:1
35 W (.5 Zo)
52.5 W
(.75 Zo)
Coupling
Transformer
Isolation
Transformer
FIGURE 13. TRANSFORMER COUPLED TEST CIRCUITS
HEAT SINKING THE LEADLESS PLASTIC
CHIP CARRIER PACKAGE
APPLICATIONS NOTE
Holt Applications Note AN-500 provides circuit design
notes regarding the use of Holt MIL-STD-1553 data
communications devices. Layout considerations, as well
as recommended interface and protection components
are included.
The HI-1575PCI/T is packaged in a 40 pin leadless plastic
chip carrier (LPCC). This package has a metal heat sink
pad on its bottom surface, which should be soldered to
the printed circuit board for optimum thermal dissipation.
The package heat sink is electrically isolated and may be
soldered to any convenient power plane or ground plane.
Redundant "vias" between the exposed board surface
and buried power or ground plane will enhance thermal
conductivity.
HOLT INTEGRATED CIRCUITS
10