At 12:29 AM 1/5/2004 +1100, you wrote:
>Dear People,
>
>I hope no-one minds me posting another question so soon after my one about
>serial comms and 628 but anyway.     I am using a 16f84 to act as a 4
>channel Digital to Analog converter using PWM.   It seems to work OK but
>what I really need to do is scale it so that it is 0 to 10v rather than 0
>to 5.    This is just a signal voltage so very little load.


                      1nF  X7R
                       ||
               +-------||----+
               |       ||    |
               |       |
        20K    |      20K    |
        ___    |      ___    |
     +-|___|---+-----|___|---|----------+
     |         |             |          |
    ===        |      12V    |          |
    GND        |     |\|     |          |
               +--- -|-\     |   ___    |
                     |  >----+--|___|---+-----o Vout
        o------------|+/
     From filter     |/|         51R

          1/2 LM358   GND

Here's a 15-cent circuit that will actually work reliably.

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

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