Advertisement

Article

Seven Steps to Successful Analog-to-Digital Signal Conversion (Noise calculation for proper signal conditioning)

Real-world signals, such as vibration, temperature, pressure, and light, require accurate signal conditioning and signal conversion before further data processing in the digital domain. In order to overcome many challenges in today’s high-precision applications, a well-designed, low-noise analog front-end is needed to get the best SNR. Many systems cannot afford the most expensive parts, nor can they afford the higher power consumption of low-noise parts.

This article presents a methodical approach to the design of a gain block and ADC including an example that supports this approach. Noise calculation and analysis is performed on this circuit when conditioning low-frequency (near dc) signals. It explains these seven steps when designing an analog front end:

  1. Describe the electrical output of the sensor or section preceding the gain block
  2. Calculate the ADC’s requirements
  3. Find the optimal ADC + voltage reference for the signal conversion
  4. Find the maximum gain and define search criteria for the op amp
  5. Find the optimal amplifier and design the gain block
  6. Check the total solution noise against the design target
  7. Run simulation and validate

The article also includes references as well as links to other articles by the author. The article is presented as a pdf file (n registration required). To read the article, click here.

About the author
Reza Moghimi is an applications engineer at Analog Devices in San Jose, CA. He received a BSEE from San Jose State University in 1984 and an MBA in 1990, and has also received a number of on-the-job certificates. He has worked for Raytheon Corporation, Siliconix, Inc., and Precision Monolithics, Inc. (PMI–which was integrated with Analog Devices in 1990). At ADI, he has served in test-, product-, and project-engineering assignments. He has written many articles and design ideas, and has given presentations at technical seminars

1 comment on “Seven Steps to Successful Analog-to-Digital Signal Conversion (Noise calculation for proper signal conditioning)

  1. ijodijfosijf
    September 23, 2015

    Real estate, on the other hand, is a business. It's about money, and as the market has shown in the last few years, when you get careless in real estate, you stand to lose a lot of it. As an agent, you're an independent contractor, which means it's up to you to manage your own business. Any agent who picks up your slack isn't handing it back to you.

    Finally, hobbies are personal, while real estate is professional. Typically, only the people with whom you choose to share your hobbies know about them, which means they don't have a huge impact on your public image. (Unless, of course, you're still collecting Beanie Babies).

    But since your conduct as a real estate agent takes place in the professional world, it has much a longer paper trail. Pretty much anyone can find out about it. Fail to satisfy a client, and you're telling her and everyone she knows that you're unreliable—which can have serious ramifications for other areas of your life.

    None of this means you shouldn't enjoy working as a Realtor. On the contrary, you're not likely to be successful if you don't. But the best agents are those who marry the pleasure they get from their work to an understanding that it's, well, work.

    2. Leads and listings, but not necessarily in that order.
    No matter what business you're in, selling is hard. As a real estate agent, however, the challenge is even greater because repeat customers are few and far in between.

    Homes, after all, are not electronics or fashion items. They're not designed to be replaced after a year, nor do they become obsolete. People buy homes with the intention of staying put. In a perfect world, your clients won't need you again for a long time.

    True, unforeseen circumstances require people to move, and according to the latest census, 69.3 percent of all movers stayed within the same county, which means more than two thirds of movers could be returning to the same Realtor. Nevertheless, altogether only 12.5 percent of the U.S. population changed residences in 2010. That's a slight increase since 2008, but in general, this share has decreased by about half since the late 1940s.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.