[sdiy] Re: Inexpensive 16 bit DAC?

[phillip m gallo]

Harry,

Yes, Two 8 bit DACs can be configured to give a razor sharp 12 bits, using
pedestrian electronics.  I am doing that right now, testing a VCO.

Addition bits have to be fought by elaboration with goof ref being the
recently mentioned Hal Chamberlain book.

12 bits is also a good limit for "building out" a DAC with resistors and
buffers (the standard being razor sharp).  For Control Voltages as much
attention should be given the Voltage Reference as to the bit depth.

Now regarding Audio, there seems to be a big divide in high depth DACs,
those meant for DC work and those intended for Audio.  Most monster Audio
Dacs are serial.

Older 16 bit DAC technolodies like the AD669 or AD660 combine both of these
interfaces in byte and word wide xface with integrated VREF.  As a DACPORT
it is a big chunk of the solution.  It's also available in DIP format but
it's pricey at DIGIKEY $22.00US. This chip is best used when double duty
(AC/DC) is expected of a DAC.

regards,
p


-----Original Message-----
From: owner-synth-diy at dropmix.xs4all.nl
[mailto:owner-synth-diy at dropmix.xs4all.nl]On Behalf Of harrybissell
Sent: Friday, April 22, 2005 4:25 PM
To: Tim Parkhurst
Cc: synthdiy
Subject: Re: [sdiy] Re: Inexpensive 16 bit DAC?


This is like saying that if a woman can have a baby in nine months, two
women can do the job in 4 1/2 months...   :^P

In most cases, two 8 bit dacs would not give the perfromance of a 16 bit
dac.
You would be lucky to get maybe 12 bits out of it.  The accuracy you need
just
isn't there.

I'm going to skip the math here... but Professor Magnus will prabably keep
you all after class and make you clap the erasers...   :^P

H^) harry

Tim Parkhurst wrote:

> > -----Original Message-----
> > From: Kevin Lightner [mailto:synthfool at synthfool.com]
> > Sent: Friday, April 22, 2005 3:23 PM
> > To: synthdiy
> > Subject: [sdiy] Re: Inexpensive 16 bit DAC?
> >
> > >Hi,
> > >
> > >I need to find an inexpensive and easy to get 16 bit parallel DAC for
> audio.
> > >Either DIP or SOIC is fine.
> > >
> > >Any suggestions?
> > >
> > >Thank you for any help.
> >
> >
> > Laugh as you might: use two 8 bit dacs.
> > They're cheap and there's many parallel styles.
> >
> > --
> > Regards,
> > Kevin Lightner
> >
>
> Hi Grant,
>
> If that approach (two 8-bit DACs) gives you the required accuracy, then
you
> might want to check out the TI TLC7528CN (PDIP 20) or TLC7528CDW (SOIC
20).
> This is a dual 8-bit MDAC with data latches (and good matching between the
> two converters). The A and B DACs have separate ref voltage inputs, so you
> could set up a different voltage range for the 'high order' and 'low
order'
> bytes. Input is 8-bit parallel.
>
> Tim (1-bit processor) Servo
>
> "Imagination is more important than knowledge." - Albert Einstein
>
> --
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