element14 Community
element14 Community
    Register Log In
  • Site
  • Search
  • Log In Register
  • Community Hub
    Community Hub
    • What's New on element14
    • Feedback and Support
    • Benefits of Membership
    • Personal Blogs
    • Members Area
    • Achievement Levels
  • Learn
    Learn
    • Ask an Expert
    • eBooks
    • element14 presents
    • Learning Center
    • Tech Spotlight
    • STEM Academy
    • Webinars, Training and Events
    • Learning Groups
  • Technologies
    Technologies
    • 3D Printing
    • FPGA
    • Industrial Automation
    • Internet of Things
    • Power & Energy
    • Sensors
    • Technology Groups
  • Challenges & Projects
    Challenges & Projects
    • Design Challenges
    • element14 presents Projects
    • Project14
    • Arduino Projects
    • Raspberry Pi Projects
    • Project Groups
  • Products
    Products
    • Arduino
    • Avnet & Tria Boards Community
    • Dev Tools
    • Manufacturers
    • Multicomp Pro
    • Product Groups
    • Raspberry Pi
    • RoadTests & Reviews
  • About Us
  • Store
    Store
    • Visit Your Store
    • Choose another store...
      • Europe
      •  Austria (German)
      •  Belgium (Dutch, French)
      •  Bulgaria (Bulgarian)
      •  Czech Republic (Czech)
      •  Denmark (Danish)
      •  Estonia (Estonian)
      •  Finland (Finnish)
      •  France (French)
      •  Germany (German)
      •  Hungary (Hungarian)
      •  Ireland
      •  Israel
      •  Italy (Italian)
      •  Latvia (Latvian)
      •  
      •  Lithuania (Lithuanian)
      •  Netherlands (Dutch)
      •  Norway (Norwegian)
      •  Poland (Polish)
      •  Portugal (Portuguese)
      •  Romania (Romanian)
      •  Russia (Russian)
      •  Slovakia (Slovak)
      •  Slovenia (Slovenian)
      •  Spain (Spanish)
      •  Sweden (Swedish)
      •  Switzerland(German, French)
      •  Turkey (Turkish)
      •  United Kingdom
      • Asia Pacific
      •  Australia
      •  China
      •  Hong Kong
      •  India
      • Japan
      •  Korea (Korean)
      •  Malaysia
      •  New Zealand
      •  Philippines
      •  Singapore
      •  Taiwan
      •  Thailand (Thai)
      • Vietnam
      • Americas
      •  Brazil (Portuguese)
      •  Canada
      •  Mexico (Spanish)
      •  United States
      Can't find the country/region you're looking for? Visit our export site or find a local distributor.
  • Translate
  • Profile
  • Settings
Experts, Learning and Guidance
  • Technologies
  • More
Experts, Learning and Guidance
Ask an Expert Forum Operational amplifier stability question
  • Blog
  • Forum
  • Documents
  • Leaderboard
  • Files
  • Members
  • Mentions
  • Sub-Groups
  • Tags
  • More
  • Cancel
  • New
Join Experts, Learning and Guidance to participate - click to join for free!
Actions
  • Share
  • More
  • Cancel
Forum Thread Details
  • State Suggested Answer
  • Replies 6 replies
  • Answers 1 answer
  • Subscribers 304 subscribers
  • Views 1014 views
  • Users 0 members are here
  • operational_amplifier
  • opamp
  • oscillation
  • stability
Related
See a helpful answer?

Be sure to click 'more' and select 'suggest as answer'!

If you're the thread creator, be sure to click 'more' then 'Verify as Answer'!

Operational amplifier stability question

Former Member
Former Member over 14 years ago

I'm designing a portable biological signal acquisition system for my licence project and while designing the mixed signal board, a potential problem came in my mind: is it stable ?

I'm using an opamp (OPA350) as a buffer for the reference voltage (I'm using the reference voltage as a virtual ground). For every instrumentation amplifier I connected a capacitor between 5V (the positive supply rail) and reference, and one between analog ground (the negative supply rail with respect to the virtual ground). Is this circuit prone to oscillation because of these capacitors ?

 

Thanks !

Attachments:
image
  • Sign in to reply
  • Cancel
Parents
  • dougw
    0 dougw over 9 years ago

    The ref opamp could be quite unstable with this capacitance load.

    image

    A small resistor on the output (in series) of the opamp is a common way to improve stability with high capacitance loads.

    A resistive load can also help.

    Here are some other methods:

    http://www.analog.com/library/analogdialogue/archives/38-06/capacitive_loading.pdf

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
Reply
  • dougw
    0 dougw over 9 years ago

    The ref opamp could be quite unstable with this capacitance load.

    image

    A small resistor on the output (in series) of the opamp is a common way to improve stability with high capacitance loads.

    A resistive load can also help.

    Here are some other methods:

    http://www.analog.com/library/analogdialogue/archives/38-06/capacitive_loading.pdf

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
Children
No Data
element14 Community

element14 is the first online community specifically for engineers. Connect with your peers and get expert answers to your questions.

  • Members
  • Learn
  • Technologies
  • Challenges & Projects
  • Products
  • Store
  • About Us
  • Feedback & Support
  • FAQs
  • Terms of Use
  • Privacy Policy
  • Legal and Copyright Notices
  • Sitemap
  • Cookies

An Avnet Company © 2025 Premier Farnell Limited. All Rights Reserved.

Premier Farnell Ltd, registered in England and Wales (no 00876412), registered office: Farnell House, Forge Lane, Leeds LS12 2NE.

ICP 备案号 10220084.

Follow element14

  • X
  • Facebook
  • linkedin
  • YouTube