100 SERIES
Acapella Optical Modem IC
ACS101A Main Features:
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Full duplex serial transmission over one fiber.
Supports asynchronous data rates from DC to 76.8kbps.
Supports synchronous data rates up to 512kbps.
Full diagnostic modes - Remote and Local loopback.
AC
Supports two additional low frequency asynchronous channels or
the RS-232 handshake signals.
Digital mode for non fiber applications - RF.
Bit Error Rate (BER) < 10
-9
Available in 44 pin PLCC package.
S1
Data
Compress
FIFO Time
Compress
Data
Decompress
FIFO Time
Decompress
RTS
DTR
DR(3:1) DM(3:1)
Uses a single Ping Pong LED (PPLED) to both receive and transmit
data for single fiber operation.
01
3B4B
Encoder
3B4B
Decoder
Control Logic
CKC PORB
A
TRC
Link lengths up to 5km.
2
TxD
TxCL
Digital
Filter
PPLED
LED
Driver
LED
Receiver
RxD
RxCL
Digital
Filter
RS-232 Interface
DCDB CTS
DSR RSS
Equivalent Block Diagram of ACS101A
ACS101A Revision 1.2 October 1999
General Description:
The ACS101A is a complete controller, driver and receiver IC, supporting full-
duplex asynchronous transmission from DC to 76.8kbps and synchronous
data rates up to 512kbps over one optical fiber. The ACS101A also supports
two additional low frequency asynchronous channels or RS-232 handshake
signals, RTS, CTS, DTR and DSR.
The ACS101A employs data compression and time compression techniques,
affording high launch power in short bursts, leading to a low average power
consumption. The advantage of this approach is that high link budgets can be
achieved with inexpensive optical components.
Communicating optical modems automatically maintain synchronisation
with each other such that the receive phase of one modem is lined-up with
the transmit phase of the other, compensating for the propagation delay
presented by the link. Link lengths from zero to maximum distance are
catered for automatically. In 'standard' mode, the fiber may be up to 2.5km
long, or up to 5km in 'double' mode.
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ACS101A Issue 1.2 October 1999.