Does anybody make a micro with 3 DACs
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From: MooseFET on 22 Apr 2010 20:43 I have an application where I need 3 DACs controlled by a micro. Right now I have a quad DAC chip external to the processor. If a small processor had 3 or more DACs, it could save me a bit of space and signal connections. 16 bitters preferred but 12 bit may work. I can't use PWM stuff because I need frequency response and low noise at the same time.
From: krw on 22 Apr 2010 20:49 On Thu, 22 Apr 2010 17:43:22 -0700 (PDT), MooseFET <kensmith(a)rahul.net> wrote: >I have an application where I need 3 DACs controlled by a micro. > >Right now I have a quad DAC chip external to the processor. If >a small processor had 3 or more DACs, it could save me a bit of >space and signal connections. > >16 bitters preferred but 12 bit may work. > >I can't use PWM stuff because I need frequency response and >low noise at the same time. I've not seen any DACs on logic devices that are worth a damn. For some reason they can make ADCs but not DACs. Sixteen bits really is pushing it.
From: Sjouke Burry on 22 Apr 2010 21:44 MooseFET wrote: > I have an application where I need 3 DACs controlled by a micro. > > Right now I have a quad DAC chip external to the processor. If > a small processor had 3 or more DACs, it could save me a bit of > space and signal connections. > > 16 bitters preferred but 12 bit may work. > > I can't use PWM stuff because I need frequency response and > low noise at the same time. connect 3 or more sample/hold amplifiers to one dac.
From: Tim Wescott on 22 Apr 2010 22:13 krw(a)att.bizzzzzzzzzzzz wrote: > On Thu, 22 Apr 2010 17:43:22 -0700 (PDT), MooseFET <kensmith(a)rahul.net> wrote: > >> I have an application where I need 3 DACs controlled by a micro. >> >> Right now I have a quad DAC chip external to the processor. If >> a small processor had 3 or more DACs, it could save me a bit of >> space and signal connections. >> >> 16 bitters preferred but 12 bit may work. >> >> I can't use PWM stuff because I need frequency response and >> low noise at the same time. > > I've not seen any DACs on logic devices that are worth a damn. For some > reason they can make ADCs but not DACs. Sixteen bits really is pushing it. I know that the 68HC11F (old part) had C/2C ladders instead of R/2R -- I wonder if that's the case for all of them, and the resistors just can't be done? Seems like you could make a dynamic DAC, put a C/2C ladder into a sample & hold, and keep updating it -- but I dunno. -- Tim Wescott Control system and signal processing consulting www.wescottdesign.com
From: Uwe Hercksen on 23 Apr 2010 03:53
Sjouke Burry schrieb: > > connect 3 or more sample/hold amplifiers to one dac. Hello, this would waste PCB space in comparison with the alternative of using a quad DAC in a small package. Bye |