ADN2873ACPZ-RL7 AD [Analog Devices], ADN2873ACPZ-RL7 Datasheet

no-image

ADN2873ACPZ-RL7

Manufacturer Part Number
ADN2873ACPZ-RL7
Description
3.3 V, 50 Mbps to 4.25 Gbps, Single-Loop, Laser Diode Driver
Manufacturer
AD [Analog Devices]
Datasheet
FEATURES
SFP/SFF and SFF-8472 MSA compliant
SFP reference design available
50 Mbps to 4.25 Gbps operation
Automatic average power control
Typical 60 ps output rise/fall time
VCSEL, DFB, and FP laser support
Bias current range: from 2 mA to 100 mA
Modulation current range: from 5 mA to 90 mA
Laser fail alarm and automatic laser shutdown (ALS)
Bias and modulation current monitoring
Voltage setpoint control
Resistor setpoint control
3.3 V supply
24-lead 4 mm × 4 mm LFCSP
Pin compatible with ADN2870
APPLICATIONS
1×/2×/4× Fibre Channel SFP/SFF modules
Multirate OC3 to OC48-FEC SFP/SFF modules
LX-4 modules
DWDM/CWDM laser transmitters
HDTV (SMPTE family) laser transmitters
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
Tx_DISABLE
Tx_FAULT
MICROCONTROLLER
ANALOG DEVICES
DAC
DAC
ADC
GND
V CC
GND
1kΩ
1kΩ
PAVREF
MPD
PAVSET
ERREF
ERSET
APPLICATIONS DIAGRAM
RPAV
VCC
V
GND
CC
Figure 1.
FAIL
GND
Single-Loop, Laser Diode Driver
IBMON
1kΩ
CONTROL
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
GENERAL DESCRIPTION
Like the ADN2870, the ADN2873 laser diode driver (LDD) is
designed for advanced SFP and SFF modules, using SFF-8472
digital diagnostics. The ADN2873 supports NRZ data
transmission operation from 50 Mbps up to 4.25 Gbps. With a
new alarm scheme, this device avoids the shutdown issue
caused by the system transient generated from various lasers.
The ADN2873 monitors the laser bias and modulation currents
and it provides fail alarms and ALS. Using setup voltages of a
microcontroller DAC or a trimmable resistor voltage divider,
the ADN2873 can set up a laser optical average output power and
extinction ratio. The optical average power control loop consists
of an optical feedback from a photodiode, the comparator, and a
status holder. The ADN2873 works easily with the Analog
Devices, Inc.,
devices and with the ADN289x family of limiting amplifiers to
make a complete SFP/SFF transceiver chipset solution.
The ADN2873 is pin compatible with the ADN2870 dual-loop
LDD, allowing the same design to work with either device. For
dual-loop control applications, refer to the ADN2870 data sheet.
The product is available in a space-saving 24-lead, 4 mm × 4 mm
LFCSP specified over the −40°C to +85°C temperature range.
Figure 1 shows an application diagram of the voltage setpoint
control with single-ended laser interface. Figure 36 shows a
differential laser interface.
GND
ALS
3.3 V, 50 Mbps to 4.25 Gbps,
×100
IMMON
470Ω
IMOD
GND
V
ADN2873
CC
PAVCAP
IMODN
ADuC7019/ADuC702x
100Ω
NC
©2008 Analog Devices, Inc. All rights reserved.
IMODP
IBIAS
CCBIAS
V
CC
L
R
V
CC
R
Z
DATAP
DATAN
LASER
family of MicroConverter®
V
CC
ADN2873
www.analog.com

Related parts for ADN2873ACPZ-RL7

ADN2873ACPZ-RL7 Summary of contents

Page 1

FEATURES SFP/SFF and SFF-8472 MSA compliant SFP reference design available 50 Mbps to 4.25 Gbps operation Automatic average power control Typical 60 ps output rise/fall time VCSEL, DFB, and FP laser support Bias current range: from 100 ...

Page 2

ADN2873 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Applications Diagram ...................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 SFP Timing Specifications ........................................................... 5 Absolute Maximum Ratings ............................................................ 6 ESD Caution .................................................................................. 6 Pin ...

Page 3

SPECIFICATIONS 3.6 V. All specifications T CC Table 1. Parameter LASER BIAS CURRENT (IBIAS) Output Current IBIAS Compliance Voltage IBIAS when ALS Is High MODULATION CURRENT (IMODP, IMODN) Output Current IMOD Compliance Voltage IMOD when ...

Page 4

ADN2873 Parameter IBMON, IMMON DIVISION RATIO 3 IBIAS/IBMON 3 IBIAS/IBMON 3 IBIAS/IBMON IBIAS/IBMON STABILITY 3, 10 IMOD/IMMON IBMON Compliance Voltage SUPPLY (with Respect to GND Temperature range is from −40°C to +85°C. 2 ...

Page 5

SFP TIMING SPECIFICATIONS Table 2. Parameter ALS Assert Time 1 ALS Negate Time 1 Time to Initialize, Including Reset of FAIL FAIL Assert Time ALS to Reset Time 1 Guaranteed by design and characterization. Not production tested. DATAP – DATAN ...

Page 6

ADN2873 ABSOLUTE MAXIMUM RATINGS Table 3. Parameter VCC to GND IMODN, IMODP All Other Pins Junction Temperature Operating Temperature Range, Industrial Storage Temperature Range Junction Temperature (T max Power Dissipation 2 θ Thermal Impedance JA θ Thermal Impedance ...

Page 7

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic 1 CCBIAS 2 PAVSET 3 GND 4 VCC 5 PAVREF 6 RPAV PAVCAP 9 GND 10 DATAP 11 DATAN 12 ALS 13 ERSET 14 ...

Page 8

ADN2873 TYPICAL PERFORMANCE CHARACTERISTICS SINGLE-ENDED OUTPUT These performance characteristics were measured using the high speed electrical single-ended output circuit shown in Figure MODULATION CURRENT (mA) Figure 7. Rise Time vs. Modulation ...

Page 9

DIFFERENTIAL OUTPUT These performance characteristics were measured using the high speed electrical differential output circuit shown in Figure MODULATION CURRENT (mA) Figure 11. Rise Time vs. Modulation Current ...

Page 10

ADN2873 PERFORMANCE CHARACTERISTICS 240 220 100 I = 90mA IBIAS 180 160 I = 40mA IBIAS 140 120 100 MODULATION CURRENT (mA) Figure 15. Total Supply Current vs. Modulation Current Total Supply Current ...

Page 11

FAIL ASSERTED FAULT FORCED ON PAVSET Figure 21. FAIL Assert Time,1 μs/DIV Figure 22. Time to Initialize, Including Reset, 40 ms/DIV Rev Page ADN2873 TRANSMISSION ON POWER SUPPLY TURNED ON ...

Page 12

ADN2873 OPTICAL WAVEFORMS V = 3.3 V and T = 25°C, unless otherwise noted. Note that there was no change to PAVCAP and ERCAP values when different data CC A rates were tested. Figure 23, Figure 24, and Figure 25 ...

Page 13

THEORY OF OPERATION Laser diodes have a current-in to light-out transfer function, as shown in Figure 28. Two key characteristics of this transfer function are the threshold current and the laser slope in the TH linear region beyond ...

Page 14

ADN2873 Tx_DISABLE Tx_FAULT ANALOG DEVICES MICROCONTROLLER DAC ADC DAC Figure 29. Using Microconverter Voltage Setpoint Calibration and Monitoring PAVREF MPD RPAV PAVSET V GND CC ERREF ERSET GND Figure 30. Using Resistor Setpoint Calibration of Average ...

Page 15

RESISTOR SETPOINT CALIBRATION In resistor setpoint calibration, the PAVREF, ERREF, and RPAV pins must all be tied to VCC. The average power and extinction ratio can be set using the PAVSET and ERSET pins, respectively. A resistor is placed between ...

Page 16

ADN2873 V CC PHOTODIODE PAVSET ADN2873 MICROCONVERTER ADC INPUT R Figure 34. Recommended Method of I MPD Sense Resistor in Resistor Setting Mode LOOP BANDWIDTH SELECTION To ensure that the ADN2873 control loop has sufficient bandwidth, the average power loop ...

Page 17

DATA INPUTS Data inputs should be ac-coupled (10 nF capacitors are recom- mended) and are terminated via a 100 Ω internal resistor between the DATAP and DATAN pins. A high impedance circuit sets the common-mode voltage and is designed to ...

Page 18

ADN2873 ALARMS The ADN2873 has a latched, active high monitoring alarm (FAIL). The FAIL alarm output is open drain in conformance with SFP MSA specification requirements. The ADN2873 has a three-fold alarm system that covers • Use of a bias ...

Page 19

... OUTLINE DIMENSIONS PIN 1 INDICATOR 1.00 0.85 0.80 SEATING PLANE ORDERING GUIDE Model Temperature Range 1 ADN2873ACPZ −40°C to +85°C 1 ADN2873ACPZ-RL −40°C to +85°C 1 ADN2873ACPZ-RL7 −40°C to +85° RoHS Compliant Part. 4.00 BSC SQ 0.60 MAX 0.50 BSC TOP 3.75 VIEW BSC SQ 0.50 0.40 0.30 0.80 MAX 12° MAX 0.65 TYP 0.05 MAX ...

Page 20

ADN2873 NOTES ©2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07493-0-6/08(0) Rev Page ...

Related keywords