Transmitter Module
channel. Status, alarm and fault information are available
via the TWS interface. The interrupt signal (selectable via
the TWS interface as a pulse or static level) is provided to
inform hosts of an assertion of an alarm, LOS and/or Tx
fault.
The optical transmitter module (see Figure 1) incorpo-
rates a 12-channel VCSEL (Vertical Cavity Surface Emitting
Laser) array, a 12-channel input buffer and laser driver, di-
agnostic monitors, control and bias blocks. The transmit-
ter is designed for IEC-60825 and CDRH eye safety com-
pliance; Class 1M out of the module. The Tx Input Buffer
provides CML compatible differential inputs (presenting
a nominal differential input impedance of 100 Ohms and
a nominal common mode impedance to signal ground
of 25 Ohms) for the high speed electrical interface that
can operate over a wide common mode range without
requiring DC blocking capacitors. For module control and
interrogation, the control interface (LVTTL compatible)
incorporates a Two Wire Serial (TWS) interface of clock
and data signals and dedicated signals for host interrupt,
module address setting and module reset. Diagnostic
monitors for VCSEL bias, light output (LOP), temperature,
both supply voltages and elapsed operating time are
implemented and results are available through the TWS
interface.
Receiver Module
The optical receiver module (see Figure 2) incorporates
a 12-channel PIN photodiode array, a 12-channel pre-
amplifier and output buffer, diagnostic monitors, control
and bias blocks. The Rx Output Buffer provides CML com-
patible differential outputs for the high speed electrical
interface presenting nominal single-ended output im-
pedances of 50 Ohms to AC ground and 100 Ohms dif-
ferentially that should be differentially terminated with
100 Ohms. DC blocking capacitors may be required. For
module control and interrogation, the control interface
(LVTTL compatible) incorporates a Two Wire Serial (TWS)
interface of clock and data signals and dedicated signals
for host interrupt, module address setting and module
reset. Diagnostic monitors for optical input power, tem-
perature, both supply voltages and elapsed operating
time are implemented and results are available through
the TWS interface.
Over the TWS interface, the user can, for individual
channels, control (flip) polarity of the differential inputs,
de-activate channels, place channels into margin mode,
disable the squelch function and program input equaliza-
tion levels to reduce the effect of long PCB traces. A reset
for the control registers is available. Serial ID information
and alarm thresholds are provided. To reduce the need for
polling, the TWS interface is augmented with an interrupt
signal for the host.
Over the TWS interface, the user can, for individual
channels, control (flip) polarity of the differential outputs,
de-activate channels, disable the squelch function,
program output signal amplitude and de-emphasis
and change receiver bandwidth. A reset for the control
registers is available. Serial ID information and alarm
thresholds are provided. To reduce the need for polling,
the TWS interface is augmented with an interrupt signal
for the host.
Alarm thresholds are established for the monitored attri-
butes. Flags are set and interrupts generated when the
attributes are outside the thresholds. Flags are also set
and interrupts generated for loss of input signal (LOS) and
transmitter fault conditions. All flags are latched and will
remain set even if the condition initiating the latch clears
and operation resumes. All interrupts can be masked and
flags are reset by reading the appropriate flag register.
The optical output will squelch for loss of input signal
unless squelch is disabled. Fault detection or channel
deactivation through the TWS interface will disable the
Alarm thresholds are established for the monitored attri-
butes. Flags are set and interrupts generated when the
attributes are outside the thresholds. Flags are also set
and interrupts generated for loss of optical input signal
(LOS). All flags are latched and will remain set even if
the condition initiating the latch clears and operation
Laser Driver
12 Channels
Tx Input Buꢀer
12 Channels
Rx Output Buꢀer
12 Channels
Preamp
12 Channels
Din[11:0][p/n] (24)
Dout[11:0][p/n] (24)
SCL
SDA
SCL
SDA
Diagnostic
Monitors
Diagnostic
Monitors
IntL
IntL
Control
Control
Adr[2:0] (3)
ResetL
Adr[2:0] (3)
ResetL
Vcc33 (4)
Vcc25 (2)
Gnd
Vcc33 (4)
Vcc25 (2)
Gnd
Bias
Bias
Figure 2. Receiver Block Diagram
Figure 1. Transmitter Block Diagram
2
5秒后页面跳转
电子元器件中的网络滤波器、EMI滤波器与EMC滤波器：分类关系与功能详解
NTC热敏电阻与PTC热敏电阻的应用原理及应用范围
GTO与普通晶闸管相比为什么可以自关断？为什么普通晶闸管不能呢？从GTO原理、应用范围带你了解原因及推荐型号
LF353数据手册解读：特性、应用、封装、引脚说明、电气参数及替换型号推荐
微信公众号
抖音公众号
浙公网安备 33010502006866号 浙ICP备10014259号-119
营业执照ICP证
数据手册
如果您发现信息不准确，
