MSGEQ7 without micro controller? - diyAudio
Go Back   Home > Forums > Live Sound > Instruments and Amps

Instruments and Amps Everything that makes music, Especially including instrument amps.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th October 2012, 07:39 AM   #1
diyAudio Member
 
Join Date: Jun 2012
Default MSGEQ7 without micro controller?

There seems to be a lot of projects using Arduino and the MSGEQ7 chip, but what about using logic circuits?

As far as I can work out the MSGEQ7 outputs a multiplexed DC signal referencing VCC, (which is 5V) for each of its 7 channels. So...

Can I just sling this signal into a 4017 decade counter, give both the chips a timing signal from a 555, and output directly into 7 LM3915's to drive "daz blinken lights"?

Am I going to need to buffer the output into/out of the 4017?

Is there anything I've missed?

I'm trying to avoid all of the programing malarkey, and doing it old school.

I'm wanting 7x10 or more LED's for each channel.
  Reply With Quote
Old 15th October 2012, 02:08 PM   #2
Simon B is offline Simon B  United Kingdom
diyAudio Member
 
Join Date: Dec 2011
Location: North-East England
Feed the 4017 from your clock, using glue logic to have that reset after count 7

Output from the MSGEQ7 is time division multiplexed analogue, so you need to separate the 7 outputs with 7 sample and hold circuits, one for each driver chip, enabled by the count from the 4017.

Signal input to the LM3915 on pin 5 is high impedance, so your sample and hold circuits may need to be just a fet, a diode and a capacitor.

Alternatively, you could ditch the 4017 and do the count in binary, then use a HEF4051B (de)multiplexer, with a small cap to ground on each output, feeding the LM3915s

Don't forget that you need to provide a reset pulse as well as the strobe.
Attached Images
File Type: gif Timing.gif (8.1 KB, 31 views)
__________________
Engineer: One who can do for 10 shillings what any fool can do for 10 pounds.
  Reply With Quote
Old 15th March 2013, 12:01 PM   #3
diyAudio Member
 
Join Date: Mar 2013
Look at the block diagram from the data sheet; you'd be better just using opamps and skipping the multiplexing at the end.

I bought these and had the same lack of interest using a micro controller, but that's really what they're for. Otherwise, you're just making redundant peak detectors.


Try taking the filter section out of this:

Nixie Music Visualizer | tchips.com
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Yamaha Micro-Controller redrooster Solid State 2 18th February 2012 03:09 AM
Samsung 1602VFD For CDROM Controller & Remote Volume Controller slowgay Swap Meet 2 22nd November 2008 02:44 PM
Micro Jacks and Micro Pins for board-board connection jazzist Parts 1 12th May 2008 03:02 PM
Modular dac project with micro controller and lcd cviller Digital Source 10 2nd January 2007 07:06 PM
digital filter using pic micro controller vish_zn Digital Source 16 20th March 2002 08:47 AM


New To Site? Need Help?

All times are GMT. The time now is 09:06 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2