tza3012ahw NXP Semiconductors, tza3012ahw Datasheet - Page 7

• Manufacturer Part Number: tza3012ahw
• Description: 30 Mbits/s Up To 3.2 Gbits/s A-ratetm Fibre Optic Receiver
• Manufacturer: NXP Semiconductors

Philips Semiconductors
FUNCTIONAL DESCRIPTION
The TZA3012AHW receives data from an incoming bit
stream having a bit rate from 30 Mbits/s up to 3.2 Gbits/s.
Two line inputs with limiting amplifiers are available.
An internal DCR synchronizes the internal clock generator
to the incoming data. The recovered serial data and clock
are demultiplexed at ratios of 1:16, 1:10, 1:8 or 1:4.
Choice of user interface
The TZA3012AHW can be controlled either via the I
or using programming pins DR0 to DR2. Pin UI selects the
user interface required. I
functionality are enabled when pin UI is either open circuit
or connected to V
when pin UI is connected to V
Table 1 Truth table for pin UI
In I
I
actions, pin CS must be HIGH. When pin CS is LOW, the
programmed configuration remains active but signals SDA
and SCL are ignored. This allows several TZA3012AHWs
in the application with the same I
selected separately. The I
TZA3012AHW is shown in Table 2.
Table 2 I
The function and content of the I
described in Section “I
the TZA3012AHW can be controlled either by the I
or a designated pin. The method required is specified by
an extra bit named I2C<pin name> in the corresponding
I
register DMXCNF. The default is enable by pin.
If the application has no I
operate with reduced functionality in pre-programmed
mode. In pre-programmed mode, pins DR0 to DR2 are
standard CMOS inputs that allow the selection of up to
eight pre-programmed bit rates using an external
reference clock frequency of typically 19.44 MHz;
see Table 3.
2003 May 21
2
2
LOW
HIGH
C-bus pins SDA and SCL. During I
C-bus register, for example, bit I2CDMXR in
A6
30 Mbits/s up to 3.2 Gbits/s
A-rate
1
UI
2
C-bus control mode, the chip is configured using the
pre-programmed
I
A5
2
0
2
C-bus control
C-bus address of the TZA3012AHW
MODE
fibre optic receiver
A4
1
CC
. Pre-programmed mode is enabled
2
C-bus registers”. Some functions in
A3
2
0
2
C-bus control and A-rate
2
C-bus control, the IC must
C-bus address of the
PIN 22
EE
DR0
A2
CS
0
; see Table 1.
2
2
C-bus registers are
C-bus address to be
2
C-bus read or write
A1
0
PIN 23
SDA
DR1
A0
0
PIN 24
2
2
DR2
SCL
C-bus
C-bus
R/W
X
7
Table 3 Truth table for selecting bit rate in
After power-up, the TZA3012AHW initiates a Power-On
Reset (POR) sequence to restore the default settings of
the I
The default settings are shown in Table 12.
Limiting amplifiers
The TZA3012AHW has two switchable RF line inputs.
Each input has a limiting amplifier (limiter) which provides
optimum receiver sensitivity at any bit rate. The bandwidth
of each limiter is automatically adjusted in accordance with
the input bit rate. This ensures that wideband noise
present in the optical front-end (photo-detector and
transimpedance amplifier) is reduced at low input bit rates.
The maximum bandwidth is selected by default at
power-up. The bandwidth can be set independently of
input bit rate using bits AMPOCT in I
LIMCNF (address C2H).
Normally, only one limiter is activated at any one time so
that only the RF signal applied to the active channel is
routed to the DCR. The unused limiter automatically enters
a sleep mode to reduce power dissipation. A limiter is
selected by pin INSEL as shown in Table 4.
Table 4 Truth table for pin INSEL
A limiter can also be selected by setting bit I2CINSEL in
I
shown in Table 5.
2
LOW
LOW
LOW
LOW
HIGH
HIGH
HIGH
HIGH
HIGH
LOW
C-bus register LIMCNF, and specifying bit INSEL as
INSEL
DR2
PIN
2
C-bus registers, irrespective of the level on pin UI.
LOW
LOW
HIGH
HIGH
LOW
LOW
HIGH
HIGH
pre-programmed mode (pin UI = V
DR1
channel 1; limiter 1 active
channel 2; limiter 2 active
SELECTED CHANNEL
LOW
HIGH
LOW
HIGH
LOW
HIGH
LOW
HIGH
DR0
STM1/OC3
STM4/OC12
STM16/OC48
STM16
GE
10GE
Fibre Channel
Fibre Channel
PROTOCOL
TZA3012AHW
FEC
2
Product specification
C-bus register
IN1 and IN1Q
IN2 and IN2Q
SELECTED
INPUTS
EE
BIT RATE
(Mbits/s)
)
2488.32
2666.06
1250.00
3125.00
1062.50
2125.00
155.52
622.08