groupUrl: https://ez.analog.com/data_converters/high-speed_dacs/
Analog.com Analog Dialogue Wiki English
Analog.com Analog Dialogue Wiki 简体中文
EngineerZone
EngineerZone
  • Site
  • User
  • Site
  • Search
  • User
EngineerZone
EngineerZone
  • Log in
  • Site
  • Search
  • Log in
  • Home
  • Blogs ⌵
    • EZ Spotlight
    • The Engineering Mind
  • Browse ⌵
    • All Groups
    • All Members
  • Support ⌵
    • 3D ToF Depth Sensing
    • A2B
    • Aerospace and Defense (ADEF)
    • Amplifiers
    • Analog Microcontrollers
    • Analysis Control Evaluation (ACE) Software
    • Audio
    • Clock and Timing
    • Condition-Based Monitoring
    • Data Converters
    • Design Tools and Calculators
    • Direct Digital Synthesis (DDS)
    • Embedded Vision Sensing
    • Energy Monitoring and Metering
    • FPGA Reference Designs
    • Industrial Ethernet
    • Interface and Isolation
    • Low Power RF Transceivers
    • MEMS Inertial Sensors
    • Motor Control Hardware Platforms
    • Optical Sensing
    • Power Management
    • Precision Technology Signal Chains
    • Processors and DSP
    • Reference Circuits
    • RF and Microwave
    • Signal Chain Power (SCP)
    • Switches/Multiplexers
    • Temperature Sensors
    • Video
    • Wide Band RF Transceivers
    • Wireless Sensor Networks Reference Library
  • About EZ
  • More
  • Cancel
  • 主页
  • 浏览 ⌵
    • 收件箱
    • 个人设置
    • 会员
    • 专区列表
  • 论坛专区 ⌵
    • 放大器专区
    • 精密转换器专区
    • 音频专区
    • ADE电能计量专区
    • MEMS和传感器专区
    • 接口和隔离专区
    • Power 中文专区
    • ADUC微处理器专区
    • 锁相环专区
    • 开关和多路复用器专区
    • 温度传感器
    • 基准电压源专区
    • 资源库
    • 论坛使用指南
    • 技术支持参考库
    • 在线研讨会
    • 论坛社群活动
    • 论坛激励活动
  • More
  • Cancel
High-Speed DACs
  • Data Converters
High-Speed DACs
Documents AD9726: Interface with the AD600
  • Q&A
  • Discussions
  • Documents
  • File Uploads
  • Video/Images
  • Tags
  • Managers
  • More
  • Cancel
  • New
High-Speed DACs requires membership for participation - click to join
  • HIGH-SPEED DAC SUPPORT COMMUNITY
  • +Documents
  • +AD768ARZ: FAQ
  • +AD9102: FAQ
  • +AD9106: FAQ
  • +AD9115: FAQ
  • +AD9116: FAQ
  • +AD9117: FAQ
  • +AD9119: FAQ
  • +AD9122: FAQ
  • +AD9129: FAQ
  • +AD9135: FAQ
  • +AD9142A: FAQ
  • +AD9144: FAQ
  • +AD9146: FAQ
  • +AD9148: FAQ
  • +AD9286: FAQ
  • +AD9712: FAQ
  • +AD9716: FAQ
  • +AD9717: FAQ
  • -AD9726: FAQ
    • AD9726: Interface with the AD600
    • AD9726_Iout equation error
  • +AD9734: FAQ
  • +AD9736: FAQ
  • +AD9739: FAQ
  • +AD9739A: FAQ
  • +AD9742: FAQ
  • +AD9744: FAQ
  • +AD9747: FAQ
  • +AD9748: FAQ
  • +AD974: FAQ
  • +AD9763: FAQ
  • +AD9765: FAQ
  • +AD9767:FAQ
  • +AD976A: FAQ
  • +AD9774: FAQ
  • +AD9776: FAQ
  • +AD9777: FAQ
  • +AD9779: FAQ
  • +AD9779A: FAQ
  • +AD977: FAQ
  • +AD977A: FAQ
  • +AD9780: FAQ
  • +AD9783: FAQ
  • +AD9786: FAQ
  • +AD9788: FAQ
  • +AD9789: FAQ
  • +DPG3: FAQ

AD9726: Interface with the AD600

Q 

AD9726 DAC output is differential and AD600 signal inputs are not fully
differential. Can AD9726 drive directly AD600 (differential), or do I have to
do converson with OP AMP?
Output of AD600 is not differential (A1CM and A2CM connected to GND). Do you
have reference desing?

 

A 

The AD600 has a gain range of 0 dB to +40 dB (X1 to X100). If you are using the
AD600 with +/- 5V supplies your maximum output is 6V pk-pk, which is (very
approximately) 2 V rms. The AD9726 delivers 40 mA pk-pk (i.e. differential
outputs with 0-20 mA flowing in each in antiphase) and I assume that you wish
the AD600 to deliver 20 mV to 2 V rms, by variation of its gain control, with
the AD9726 programmed to full-scale digital input. Unless you are working at
the maximum output frequency of the AD9726 you will not need to run the AD9726
at such a high current, but you should not run it at such a low current that
feeding that current into 100 Ohms gives you your 20 mV rms.

You will therefore need to arrange for the AD9726 run at a lower output current
by use of an appropriate resistor on the FSADJ pin and to deliver 20 mV rms to
the AD600.

I cannot see any need for an amplifier here, you have ample signal to spare -
you can do a perfectly adequate job with resistors or with a transformer.

Assume that your programmed total output current is X mA, then the pk-pk output
current is 2X mA and the rms. output current is X/SqRoot2 mA.

The simplest solution seems to me to be to ground one output and allow
X/(2.SqRoot2) mA rms to flow from the other output in a grounded load resistor
R to give 20 mV rms. This calls for R = (40.SqRoot2/X) Ohms. Couple this
voltage to the AD600 input with a capacitor to provide DC isolation (otherwise
the AD600 output will have a DC bias). The value of R may need to be altered to
compensate for the parallel Zin of the AD600 (100 Ohms) but in practice this
error may be trimmed out in other ways.

If you wish the above circuit to be balanced you can terminate the unused
AD9726 output with another resistance of R instead of simply grounding it. NOTE
THAT YOU MUST NOT LEAVE THIS UNUSED OUTPUT OPEN CIRCUIT.

Instead of using unbalanced coupling you can use a broadband transformer with a
centre-taped primary. The centre tap is grounded and the differential outputs
of the AD9726 feed opposite ends of the primary. The secondary is connected to
the AD600 AinHi and to ground. AinLO of the AD600 is also grounded. With this
arrangement it is necessary to shunt either the primary or the secondary of the
transformer with a resistor to prevent the AD600 input signal from being too
large. The value of the resistor will depend on the AD9726 output current
programmed and the transformer ratio.

  • ad9726
  • Share
  • History
  • More
  • Cancel
Comments
Anonymous
Related
 
社交网络
快速链接
  • 关于ADI
  • Partners
  • 模拟对话
  • 职业
  • 联系我们
  • 投资信息
  • 新闻中心
  • 质量和可靠性
  • 办事处与代理商
  • Analog Garage
语言
  • English
  • 简体中文
  • 日本語
  • Руccкий
电子快讯

欲获得最新ADI产品、设计工具、培训与活动的相关新闻与文章,请从我们的在线快讯中选出您感兴趣的产品类别,每月或每季度都会发送至您的收件箱。

订阅
Switch to mobile view
Analog Logo
© 1995 - 2022 Analog Devices, Inc. All Rights Reserved 沪ICP备09046653号-1
  • ©
  • 1995 - 2022 Analog Devices, Inc. All Rights Reserved
  • 沪ICP备09046653号-1
  • 网站地图
  • 隐私和保密政策
  • 隐私设置
  • 使用条款
 
Social
Quick Links
  • About ADI
  • Partners
  • Analog Dialogue
  • Careers
  • Contact us
  • Investor Relations
  • News Room
  • Quality & Reliability
  • Sales & Distribution
  • Analog Garage
Languages
  • English
  • 简体中文
  • 日本語
  • Руccкий
Newsletters

Interested in the latest news and articles about ADI products, design tools, training and events? Choose from one of our 12 newsletters that match your product area of interest, delivered monthly or quarterly to your inbox.

Sign Up
Switch to mobile view
Analog Logo
© 1995 - 2022 Analog Devices, Inc. All Rights Reserved 沪ICP备09046653号-1
  • ©
  • 1995 - 2022 Analog Devices, Inc. All Rights Reserved
  • 沪ICP备09046653号-1
  • Sitemap
  • Privacy & Security
  • Privacy Settings
  • Terms of use
EngineerZone Uses cookies to ensure you get the best experience in our community. For more information on cookies, please read our Privacy & Security Statement.