ACS103 Issue 2.03 May 1996.

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ACS103 - 3 Channel, Synchronous or Asynchronous Single Fiber Modem

ACS103

Acapella Optical Modem IC

3 Channel, Synchronous or Asynchronous Single Fiber Modem

Main Features:

*

Enables three full-duplex serial transmission

channels through a single fiber optic cable,

providing a virtual six fiber path.

*

Link lengths up to 5 km.

*

Uses a single Ping Pong LED (PPLED) to both

transmit and receive data.

*

Supports 7 synchronous data rates up to 64 kbps

or asynchronous data rates from DC to 19.2/

9.6 kbps.

*

Supports three additional low frequency

asynchronous channels or RS-232 handshake

signals: RTS, CTS, DTR and DSR.

*

*

Digital mode, allowing the user to add an

external amplifier. Also enables the ACS103 be

used in non-fiber applications e.g. IR/RF.

*

ACS101

emulation

mode

giving

100 %

compatibility with the ACS101.

General Description:

The ACS103 is a complete synchronous optical-

modem controller/driver IC, supporting various

user-programmable, full-duplex data-rates to

256 kbps over a single fiber. Alternatively, up to 3

channels of 64 kbps each can be carried.

In

'Standard' mode, the fiber may be up to 2.5 km long,

or up to 5 km in 'Double' mode.

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.

The ACS103 incorporates ACS101 functionality, with

additional logic to support 3 channels.

Inter-IC Encoding Technique

The

3B4B

encoding

method

is

used

for

communication between ACS103s, thus ensuring

that there is no DC component in the signal. The

encoding and decoding is transparent to the user.

DCDB RTS CTS DTR DSR XI3 XO3 RSS

CKC

SEL

XI1 XO1 XI2 XO2

FIFO

Compress

FIFO

Decompress

Digital

Filter

TxD1

TxD2

TxD3

RS-232 Interface

RxD1

RxD3

RxD2

RxCL

TxCL

GND

VA+

VD+

Digital

Filter

LED Driver

LED Receiver

Control Logic

GND

PPLED

LDN

CNT

TRC

LDP

3B4B

Decoder

3B4B

Encoder

XTAL

Block diagram of ACS103

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