1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Electronics extending hdd utilization meter

Discussion in 'Modding' started by Aldiwahn_Teerodi, 17 Mar 2006.

  1. Aldiwahn_Teerodi

    Aldiwahn_Teerodi New Member

    Joined:
    29 Oct 2004
    Posts:
    22
    Likes Received:
    0
    hello,
    maybe you know this guide from gideon-tech: http://www.gideontech.com/content/articles/205/3

    i want to build it but with 20 instead of 10 leds. though not stretched to use 20 leds but have 10 leds and mirror them so that the middle is lit up when hdd utilization is low going to the edges with higher utilization.
    something like this
    Code:
    [.........OO.........]  <- low utilization
    [........OOOO........]  <- higher utilization
    [....OOOOOOOOOOOO....]  <- even higher utilization
    
    my thought was building 2 circuits which get the signal from the same source (e.g. only one opto-coupler) as the lm3914's max sink current appears to be 13 mAs. are there any simpler/better solutions?

    any help appreciated :)
     
  2. DR_D

    DR_D New Member

    Joined:
    8 Nov 2005
    Posts:
    15
    Likes Received:
    0
    why not just double up on leds? eg. just run 2 leds of each output of the LM3914
     
  3. Aldiwahn_Teerodi

    Aldiwahn_Teerodi New Member

    Joined:
    29 Oct 2004
    Posts:
    22
    Likes Received:
    0
    i thought about that but am not sure if it would work, hence my question.
     
  4. cpemma

    cpemma Ecky thump

    Joined:
    27 Nov 2001
    Posts:
    12,328
    Likes Received:
    55
    If the LEDs are in series, and the supply voltage a few volts more than the sum of the forward voltages, no problem. It's the method used on macroman's 20-LED Knight Rider.

    The 5V supply used in the Gideontech circuit probably won't be enough for 2 x 2V leds, but that's just my guess. But no problem going to 12V, maybe double-up the two pd resistors (330R and 470R) to 680R and 1k. And I think Marsupial has the 220uF cap wrong way round on the circuit diagram, 'white box' is positive side. :duh:
     
  5. DR_D

    DR_D New Member

    Joined:
    8 Nov 2005
    Posts:
    15
    Likes Received:
    0
    as long as they LM3914 can provide enough amps on its output it will be possible to connect up 2 led's in parralel to one of the outputs. I am assuming that the outputs are 5V. if it can't provide you with enough power then your suggestion of using 2 LM3914's connected to the opto-couple will also work if i'm not mistaken.

    I could be wrong though, its been 6 years since i completed my electronics degree and i haven't used any of that knowledge since.
     
  6. Aldiwahn_Teerodi

    Aldiwahn_Teerodi New Member

    Joined:
    29 Oct 2004
    Posts:
    22
    Likes Received:
    0
    thanks for your answers.
    DR_D, as far as i can tell, the lm3914 acts as a sink, not as a source.
    i'll look through the datasheet again and see if 2 leds instead of one would work.
     
  7. DR_D

    DR_D New Member

    Joined:
    8 Nov 2005
    Posts:
    15
    Likes Received:
    0
    ah, i should have read the spec sheet and i would have seen that. so ignore what i said
     
  8. Aldiwahn_Teerodi

    Aldiwahn_Teerodi New Member

    Joined:
    29 Oct 2004
    Posts:
    22
    Likes Received:
    0
    just FYI i've built the circuit with 20 LEDs, i simply put each second LED in series with the original and it works (at least with red LEDs) :)
     
  9. Rsx

    Rsx New Member

    Joined:
    3 Jan 2005
    Posts:
    21
    Likes Received:
    0
    Are rezistors necesery for led's?
     
  10. Chancy99

    Chancy99 New Member

    Joined:
    24 Apr 2006
    Posts:
    2
    Likes Received:
    0
    Have a look at Cylon Eyes bargraph and look at the .003 MOV file. Excuse the loud noise from the systems ...

    I'll have a small kit available shortly for this. I can provide either just the programmed microcontroller, or a complete built board - you provide the LEDs.

    Dean.
     

Share This Page