Acapella Optical Modem IC

ACS401 Main Features:

LED Driver

4

3

4

PIN Receiver

RxD1

RxCL

RxD4

RxD3

RxD2

VA+

VD+

GND

TxCL

FIFO

Compress

Digital

Filter

3B4B

Encoder

TxD4

TxD3

TxD2

TxD1

FIFO

Decompress

3B4B

Decoder

Digital

Filter

GND

CNT

XTAL

PINN

PINP

LAP

Status

Control Data

Control Logic

LAN

PPLED

Single

Fiber

TRC

Equivalent block diagram of ACS401.

XO1 XI1 XO2 XI2

HBT CLK9 ERRC ERRL

DR(1:3) DM(1:3) DP(1:4)

PORB

CKC

The ACS401

is

a

complete

optical-modem

controller/

driver/receiver IC, supporting various user programmable, full-

duplex, synchronous data rates to 128 kbps over a single fiber.

Communicating modems automatically maintain synchronis-

ation 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, up to 95 km, are catered for

automatically.

General Description:

* Enables up to four full-duplex serial transmission channels

through a single fiber optic cable, providing eight virtual fiber

paths.

* Two additional low speed handshake signals.

* Supports Ping Pong LED (PPLED) and LASER Duplex

Devices (LDD) for single fiber applications or dual fiber

applications using low cost LED/LASER emitters and PIN

Diode receiver.

* Link lengths up to 95 km with appropriate Laser.

* Maximum data rate 128 kbps - optimised for talk-set

applications.

* Typical 7 mA (average) current consumption, including

LASER drive current.

* Digital mode, allowing the user to add an external amplifier.

Also enables the ACS401 to be used in non-fiber applications.