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Advanced Communications
ACS102A Data Sheet
Description
The ACS102A is a complete controller, driver and receiver IC, supporting full-
duplex asynchronous transmission from DC to 162kbps over a single serial link.
Although primarily designed for single optical fibre applications, any other simple
serial media may be used. The ACS102A is optimised for very low power
consumption, consuming only 2 - 3mA at RS-232 data rates including power
provided to the LED and 'heartbeat' monitor. In applications where the power is
extracted from the RS232 data lines, this leaves a generous amount of power left
for any power extraction and RS-232 level shifting circuitry.
The ACS102A 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.
For example, the recommended set-up for RS-232 applications (19.2kbps +
handshake signals) assumes that the LED is driven with a peak current of
approximately 15.4mA for 6 % of the time. The machine cycle is short enough to
facilitate power supply smoothing with a small external capacitor in the region of
100µF.
ACS102A
* Full duplex serial transmission over single/twin fiber.
* Link lengths up to 25km.
* Supports asynchronous data rates from DC to 162kbps.
* Full diagnostic modes - Remote and Local loopback.
* Ultra low power consumption, typically 2-3mA, which could be
extracted from the RS-232 port for self powered applications.
* Uses a single Ping Pong LED or Laser Duplex Device for single fiber
applications, low cost LED/PIN or Laser/PIN combinations for twin
fiber applications.
* Additional operating mode to support PIN with integrated TIA.
* Supports 3 additional low frequency asynchronous channels or
the RS-232 handshake signals.
* Digital and differential voltage input modes, plus modes for non
fiber applications - RF
* Bit Error Rate (BER) < 10
-9
* Available in 44 pin TQFP (part no: ACS102A-TQ) and 44 pin
PLCC (part no: ACS102A-PL) packages.
Equivalent Block Diagram of ACS102A
LED/Laser
Driver
LED/PIN
Receiver
Data
Compress
3B4B
Encoder
Digital
Filter
Data
Decompress
3B4B
Decoder
Digital
Filter
RS-232 Interface Control Logic
DCDB CTS DSR RTS DTR DR(3:1) DM(3:1) DP
PPLED
LDD
LED/PIN
Laser/PIN
combinations
TRC
TxD
RxD
FIFO Time
Decompress
FIFO Time
Compress
PORBRIO RII HD(2:1) HBT ERL
Features
ACS102A Fiber Modem
100 SERIES
ACS102A Revision 1.6 September 2000