AVR-Chat

It is a good suggestion to use MCP4922 since it is cheaper than 
AD7528 but it is running out of stock over here. I could get AD7528 
though. Anyway, can you show me how to interface MCP4922 with Atmega 
16 if it were to design 4xDAC and also some of the codes? Regards.





--- In AVR-Chat@yahoogroups.com, "Roy E. Burrage" <RBurrage@...> 
wrote:
>
> The '7528 is over 30 years old...1970s technology.  I don't 
remember if 
> it was invented by Precision Monolithics or Analog Devices with 
PMI as a 
> second source, but it's old technology and if you're developing a 
> product intending to use them you'll eventually have issues trying 
to 
> buy them.  With their parallel interface they also require more 
lines to 
> talk back and forth.
> 
> If you insist upon using the AD7528, the datasheet has fairly 
complete 
> information as to how to interface with your controller.  If need 
be you 
> can also go to the Analog Devices web site for application note 
> information.  They generally have good information up there.  You 
might 
> also check to see what the production status of the AD7528 is 
while 
> you're there.
> 
>           http://www.analog.com/en/
> 
> However, the MCP4922 is only about 3 bucks in 1s...and Microchip 
used to 
> be pretty liberal with their sample policy.
> 
> 
> REB
> 
> 
> 
> 
> huiyangdoh wrote:
> 
> >Yeah I know. In fact MCP4725 is my first choice but since I 
couldn't 
> >get it from the shop here, I would go with AD7528. So, any 
> >suggestion to design the 4X DAC using AD7528 for Atmega16? I 
crack 
> >my mind to search for this topic using Google but to no avail. 
> >
> >
> >--- In AVR-Chat@yahoogroups.com, "Roy E. Burrage" <RBurrage@> 
> >wrote:
> >  
> >
> >>You might do better using something like a Microchip MCP4922.  
It 
> >>    
> >>
> >has a 
> >  
> >
> >>serial SPI interface, 12 bit accuracy, 14 pin dip package, dual 
> >>    
> >>
> >DAC, and 
> >  
> >
> >>rail to rail outputs for starters.  We use the MCP4921 single 
DAC 
> >>version here regularly with good results.  We have used 
the '4922 
> >>    
> >>
> >in a 
> >  
> >
> >>couple of applications with good results too.  This would give 
you 
> >>    
> >>
> >a 
> >  
> >
> >>smaller package, higher accuracy module with better crosstalk, 
> >>    
> >>
> >lower 
> >  
> >
> >>power consumption, and better temperature specifications.  They 
> >>    
> >>
> >only 
> >  
> >
> >>operate at 5 volts, but if you need higher voltage operation 
you'd 
> >>    
> >>
> >have 
> >  
> >
> >>to add interface circuitry anyway between your controller and 
your 
> >>    
> >>
> >DAC.
> >  
> >
> >>They're cheap, too.
> >>
> >>
> >>REB
> >>
> >>
> >>huiyangdoh wrote:
> >>
> >>    
> >>
> >>>I am trying to develop DAC circuitry for Atmega 16 since 
Atmega16
> >>>doesn't have in-built feature of DAC. The circuitry design will 
> >>>      
> >>>
> >be 4X
> >  
> >
> >>>DAC design using AD7528 DAC Chips. To my understanding,the 4X 
DAC 
> >>>circuit would be using 11 ports lines of Atmega16 where PortC0-
> >>>      
> >>>
> >PortC7 
> >  
> >
> >>>would be input to the 8-bit parallel AD7528 chip and 3 ports 
> >>>      
> >>>
> >lines 
> >  
> >
> >>>(PortD0-Port2)would be used as control line inputs. The 
> >>>      
> >>>
> >requirement of 
> >  
> >
> >>>this DAC circuit is that it would produce variable voltage 
(0DVc -
> >>>      
> >>>
> > 
> >  
> >
> >>>10DVc) at fix current of 25mA. I will plan to locate Op Amp in 
> >>>      
> >>>
> >the 
> >  
> >
> >>>output of every AD7528 DAC chip. 
> >>>
> >>>I am not trying to ask anyone to do homework for me but I may 
> >>>      
> >>>
> >treat
> >  
> >
> >>>here as a resource to gain ideas for the development I am 
working 
> >>>      
> >>>
> >on.
> >  
> >
> >>>I will appreaciate anyone helping me by having discussions and 
> >>>      
> >>>
> >making
> >  
> >
> >>>suggestions related to this topic. Kindly show me any link 
> >>>      
> >>>
> >related to 
> >  
> >
> >>>this topic if u know any. Best Regards.  
> >>>
> >>>
> >>> 
> >>>
> >>>      
> >>>
> >
> >
> >
> >
> > 
> >Yahoo! Groups Links
> >
> >
> >
> >
> >
> >  
> >
> 
> 
> [Non-text portions of this message have been removed]
>