ACT15530CFB AEROFLEX [Aeroflex Circuit Technology], ACT15530CFB Datasheet - Page 7

• Manufacturer Part Number: ACT15530CFB
• Description: CMOS Manchester Encoder / Decoder
• Manufacturer: AEROFLEX [Aeroflex Circuit Technology]

Aeroflex Circuit Technology
Decoder Operation
frequency of 12 times the desired data rate
applied at the DECODER CLOCK input. The
Manchester II coded data can be presented to the
Decoder in one of two ways. The BIPOLAR
ONE and BIPOLAR ZERO inputs will accept
data from a comparator sensed transformer
coupled bus as specified in MIL-STD-1553. The
UNIPOLAR DATA input can only accept
non-inverted Manchester II coded data (e.g.from
BIPOLAR ZERO OUT of an Encoder).
monitors its data input lines for a valid sync
character and two valid Manchester data bits to
start an output cycle.. When a valid sync is
recognized
COMMAND/DATA SYNC output. if the sync
character was a command sync, this output will
go high
DECODER
otherwise it will remain low. The TAKE DATA
The Decoder requires a single clock with a
The Decoder is free running and continuously
y
x
Command/Data
Serial Data Out
, the type of sync is indicated on
SHIFT
and remain high for sixteen
Shift Clock
Valid Word
Take Data
Decoder
Bipolar
Bipolar
Timing
Zero In
One In
Sync
CLOCK
(From Previous
Reception)
Half Half
Sync Sync
1st
0
Undefined
periods
Figure 10: Decoder Operation
1 2
2nd
15 14 13 12 11 10
15 14 13 12 11 10
3
z
4
,
1
5
15 14 13 12
7
2
6
output will go high and remain high
while the Decoder is transmitting the decoded
data through SERIAL DATA OUT. The decoded
data available at SERIAL DATA OUT is in a
NRZ format. The DECODER SHIFT CLOCK is
provided so that the decoded bits can get shifted
into an external register on every low-to-high
transition of this clock
transmitted
A high on VALID WORD output
successful reception of a word without any
Manchester or parity errors. At this time the
Decoder is looking for a new sync character to
start another output sequence.
input
low-to-high transition of DECODER SHIFT
CLOCK will abort transmission and initialize
the Decoder to start looking for a new sync
character.
7
After all sixteen decoded bits have been
At any time in the above sequence, a high
8
on
16 17 18 19
2
2
z
4
DECODER
1
1
the data is checked for odd parity.
3
0
0
2
SCD15530 REV B 7/28/99 Plainview NY [phone]
P
P
1
y
3
0
-
z
RESET
4
.
{
indicates a
during
y
-
z
a