CN0388 Datasheet, PDF (1/5 Pages) Analog Devices – Devices Connected

Circuit Note
CN-0388
Circuits from the Lab® reference designs are engineered and
tested for quick and easy system integration to help solve today’s
analog, mixed-signal, and RF design challenges. For more
information and/or support, visit www.analog.com/CN0388.
Devices Connected/Referenced
ADN4651
5 kV RMS, 600 Mbps, Dual-Channel
LVDS Isolator
AD7960
18-Bit, 5 MSPS PulSAR Differential ADC
ADuM4400 5 kV RMS Quad-Channel Digital Isolator
ADuM2251 Hot Swappable, Dual I2C Isolators, 5 kV
Isolated 600 Mbps, LVDS, 18-Bit, 5 MSPS Data Acquisition System
EVALUATION AND DESIGN SUPPORT
Circuit Evaluation Boards
CN-0388 Circuit Evaluation Board (EVAL-CN0388-FMCZ)
AD7960 Evaluation Board (EVAL-AD7960-FMCZ)
SDP-H1 System Demonstration Platform, High Speed
(EVAL-SDP-CH1Z)
Design and Integration Files
Schematics, Layout Files, Bill of Materials
CIRCUIT FUNCTION AND BENEFITS
The circuit shown in Figure 1 demonstrates isolation of an analog
front end (18-bit, 5 MSPS AD7960 analog-to-digital converter
(ADC)) at 600 Mbps using the ADN4651 LVDS isolator. An
interposer board with the ADN4651 connects to the standard
AD7960 evaluation platform, isolating the analog front end board
from the high speed SDP-H1 system demonstration platform
(EVAL-SDP-CH1Z). The SDP-H1 contains a Xilinx Spartan 6
FPGA to capture acquisitions and a ADSP-BF527 DSP to
communicate with the PC.
Galvanic isolation of external interfaces is required in harsh
environments for safety, functionality, or improved noise
immunity. This includes analog front ends used in data
acquisition modules for industrial measurement and control.
Bandwidth requirements for converter interfaces are increasing,
as trends such as Industry 4.0 and the Internet of Things (IoT)
demand far more ubiquitous measurement and control, with
greater speed and precision. This poses a challenge for isolation,
because even standard digital isolators are limited to 150 Mbps
operation.
For measurement and control applications in industrial
environments, the benefits of such an isolated analog front-end
implementation include:
 Ease of design due to the drop-in LVDS isolator with fully
compliant input/output and ultralow jitter.
 High bandwidth of 600 Mbps to support increased ADC
resolution and speed.
 Galvanic isolation for protection from mains voltages,
isolated measurement of power supplies, or noise
immunity from digital or power supply circuits.
The circuit in Figure 1 demonstrates an industry-leading
solution to LVDS isolation at 600 Mbps using the ADN4651
dual-channel isolator.
Rev. 0
Circuits from the Lab® reference designs from Analog Devices have been designed and built by Analog
Devices engineers. Standard engineering practices have been employed in the design and
construction of each circuit, and their function and performance have been tested and verified in a lab
environment at room temperature. However, you are solely responsible for testing the circuit and
determining its suitability and applicability for your use and application. Accordingly, in no event shall
Analog Devices be liable for direct, indirect, special, incidental, consequential or punitive damages due
to any cause whatsoever connected to the use of any Circuits from the Lab circuits. (Continued on last page)
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone]
www.analog.com
Fax: [phone]
©2016 Analog Devices, Inc. All rights reserved.