Pin Designations
Pin
1
2
3
4
5
6
7
8
9
10
Input
Output
Enc
Dec
Function
Valid word
Encoder Shift Clock
Comment
A 'high' signals the receipt of a valid word
Shifts data into the encoder on a 'low' to 'high'
transition
'high' during data reception after the sync pulse is
identified
NRZ output of received data
Clock for the transition finder and synchronizer which
generates the clock for the rest of the decoder
Should be 'high' when the bus is in a negative state.
Must be tied 'high' when the unipolar input is used
Should be 'high' when the bus is in a positive state.
Must be tied 'low' when the unipolar input is used
Input for unipolar data to the transition finder. Must be
tied 'low' when not used
Provides the DECODER CLOCK divided by 12,
synchronized by the recovered serial data
This output indicates the type of synchronizing
character received as follows: If a data synchronizing
character was received, this pin is low while the data
is decoded. If a command synchronizing character
was received, this pin is high during data decoding
A 'high' during a DECODER SHIFT CLOCK rising
edge resets the bit counter
Ground
A 'high" clears the counters in both sections
Provides the ENCODER CLOCK divided by 6
Provides an active 'low' output to the zero or negative
sense of a bipolar line driver
A 'low' inhibits the BIPOLAR ZERO OUT and
BIPOLAR ONE OUT by forcing them to inactive, 'high',
states
Provides an active 'low' output to the one or positive
sense of a bipolar line driver
Receives serial data at the rate of the ENCODER
SHIFT CLOCK
A 'high' starts the encode cycle provided that the
previous cycle is complete
A 'high' selects the command sync and a 'low' selects
the data sync
Provides an active 'high' to enable the external serial
data source
Clock input at 2 times the data rate
Input to the divide by 6 circuit
Positive Supply
Take Data
Serial Data Out
Decoder clock
Bipolar Zero In
Bipolar One In
Unipolar Data In
Decoder Shift Clock
Command/Data Sync
11
12
13
14
15
16
–
–
–
Decoder Reset
V
SS
Master Reset
÷
6 Out
Bipolar Zero Out
Output Inhibit
17
18
19
20
21
22
23
24
Bipolar One Out
Serial Data In
Encoder Enable
Sync Select
Send Data
Send Clock In
Encoder Clock
–
V
DD
Figure 4: Pin Designations (24-Pin Dip/FlatPack)
Aeroflex Circuit Technology
3
SCD15530 REV B 7/28/99 Plainview NY (516) 694-6700
AEROFLEX [ AEROFLEX CIRCUIT TECHNOLOGY ]
