element14 Community
element14 Community
    Register Log In
  • Site
  • Search
  • Log In Register
  • About Us
  • 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 Boards Community
    • Dev Tools
    • Manufacturers
    • Multicomp Pro
    • Product Groups
    • Raspberry Pi
    • RoadTests & Reviews
  • 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
      •  Korea (Korean)
      •  Malaysia
      •  New Zealand
      •  Philippines
      •  Singapore
      •  Taiwan
      •  Thailand (Thai)
      • 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
Data Conversion
  • Challenges & Projects
  • Project14
  • Data Conversion
  • More
  • Cancel
Data Conversion
Blog Rough vADC demo, ADCing
  • Blog
  • Forum
  • Documents
  • Events
  • Polls
  • Files
  • Members
  • Mentions
  • Sub-Groups
  • Tags
  • More
  • Cancel
  • New
Join Data Conversion to participate - click to join for free!
  • Share
  • More
  • Cancel
Group Actions
  • Group RSS
  • More
  • Cancel
Engagement
  • Author Author: baldengineer
  • Date Created: 7 Mar 2021 10:24 PM Date Created
  • Views 1234 views
  • Likes 8 likes
  • Comments 0 comments
  • visual adc
  • baldengineer
  • dataconverch
Related
Recommended

Rough vADC demo, ADCing

baldengineer
baldengineer
7 Mar 2021

You don't have permission to edit metadata of this video.
Edit media
x
image
Upload Preview
image

 

Short update. During my live stream today, we played with a small TFT LCD module. I shot this short video after the stream. It demonstrates the ADC digitizing an input voltage of 4.23 volts. Notice the 4-bit DAC shows the binary search. The LCD screen shows the DAC's current voltage. At the very end, you can see it go from 4.2 to 4.5 volts briefly before it settles on 4.2 volts. Missing from this video is the comparator's output. It is ON when the DAC needs to go to a higher voltage and OFF when it needs to go lower. The entire binary search algorithm is very cool, at least to me. I'll be writing that up shortly.

 

Getting the project to this point took longer than I expected. The process started with understanding how we can display information on the selected LCD. After a couple of hours debugging an easy mistake (forgetting to connect VCC to anything) and playing with the Adafruit_GFX library, we had a path forward. We decided the display looked best with either 1 or 2 lines of text, with the text centered.

 

Display Modes

At the moment, I am thinking about the final version of vADC. It will display the output voltage in two ways:

  1. Single Line. In this mode, it'll show the actual voltage of the DAC while searching. When complete, the value shown is the "low end" of the available binary codes.
  2. Two Line. This mode's first line is the "low" end, and the second line is the "high" end. So if the DAC settles on 0.90V, it will display 0.9 and 1.2V to indicate the input voltage is between those two values.

 

Of course, as I write this, I think a third display option is the DAC voltage on line 1 and the binary code on line 2. Not sure yet. Any ideas? If so, let me know below.

 

Next Steps

In project-time, the next steps are to the LCD, pushbuttons, and Arduino Nano EveryArduino Nano Every to a permaboard. Then, it is time to think of an enclosure. (Which is mostly going to be brackets.) Then some more coding to round out a few more features I'd like to add. While I have the components (and PCBs), I don't think I will have time to add additional bits to the DAC before the March 15th deadline.

 

In write-up time, next, I'd like to talk about how the binary search works. I also need to update the schematic for the front-end because I'm now using an LM339 LM339 comparator.

  • Sign in to reply
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