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Octal eight-bit DAC for 80 cents

Started by Phil Hobbs February 21, 2018
The Rohm BH226F.  If it's any good, it could replace a lot of PWMs.

https://www.digikey.com/short/qptnn7

Anybody used them?

Cheers

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
https://hobbs-eo.com
On 02/21/2018 10:22 AM, Phil Hobbs wrote:
> The Rohm BH226F. If it's any good, it could replace a lot of PWMs. > > https://www.digikey.com/short/qptnn7 > > Anybody used them? > > Cheers > > Phil Hobbs >
The settling time and and integral nonlinearity specs are very Meh; 100uS (Min) - jeez, for real? I think the TI quad DAC08 variants with SPI like D084S085 are pretty nice for a buck
On 02/21/2018 10:58 AM, bitrex wrote:
> On 02/21/2018 10:22 AM, Phil Hobbs wrote: >> The Rohm BH226F.  If it's any good, it could replace a lot of PWMs. >> >> https://www.digikey.com/short/qptnn7 >> >> Anybody used them? >> >> Cheers >> >> Phil Hobbs >> > > The settling time and and integral nonlinearity specs are very Meh; > 100uS (Min) - jeez, for real?
Well, it's to replace a bunch of PWMs. ;)
> > I think the TI quad DAC08 variants with SPI like D084S085 are pretty > nice for a buck
Those are nicer, for sure, but twice as much money. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net https://hobbs-eo.com
Phil Hobbs wrote...
> > The Rohm BH2226F.
BH2221 12-channels. -- Thanks, - Win
On 02/21/2018 04:08 PM, Winfield Hill wrote:
> Phil Hobbs wrote... >> >> The Rohm BH2226F. > > BH2221 12-channels. > >
Have you used it for anything? Thanks Phil -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
On 02/21/2018 03:43 PM, Phil Hobbs wrote:
> On 02/21/2018 10:58 AM, bitrex wrote: >> On 02/21/2018 10:22 AM, Phil Hobbs wrote: >>> The Rohm BH226F.  If it's any good, it could replace a lot of PWMs. >>> >>> https://www.digikey.com/short/qptnn7 >>> >>> Anybody used them? >>> >>> Cheers >>> >>> Phil Hobbs >>> >> >> The settling time and and integral nonlinearity specs are very Meh; >> 100uS (Min) - jeez, for real? > > Well, it's to replace a bunch of PWMs. ;) > >> >> I think the TI quad DAC08 variants with SPI like D084S085 are pretty >> nice for a buck > > Those are nicer, for sure, but twice as much money. > > Cheers > > Phil Hobbs >
I use the ATTiny85 as a "general purpose low-frequency thing building block" that's under a dollar, I got this software suite that lets you drag-and-drop functional blocks like clocks, counters, PWM outputs, etc. "wire" them up into a system, assign port numbers, push a button and it generates C++, compiles it and uploads it to the uP for testing in under 30 seconds. The Rohm chip might make a good team with the ATTiny, the main flaw in a lot of applications is it only has three hardware PWM outputs on fixed pins, one of which ties up an ADC channel if you use it. Stepping up to a core with any more than three hardware PWM channels is a significant increase in footprint and price
Phil Hobbs wrote...
> > Winfield Hill wrote: >> Phil Hobbs wrote... >>> >>> The Rohm BH2226F. >> >> BH2221 12-channels. >> > Have you used it for anything?
Not that one, but other Rohm stuff, I'm happy to believe their specs. -- Thanks, - Win
bitrex wrote...
> > I use the ATTiny85 as a "general purpose low-frequency thing ...
I'm getting down on using PWM outputs, DACs are so cheap. -- Thanks, - Win
There is a crapload of microes that has fast 12bit DACs 

PWM has slow response, if you need 12 bit accuracy. And injects noise from the supply

Cheers

Klaus 
On Wednesday, February 21, 2018 at 3:57:32 PM UTC-8, Klaus Kragelund wrote:
> There is a crapload of microes that has fast 12bit DACs > > PWM has slow response, if you need 12 bit accuracy. And injects noise from the supply
The ROHM devices are R/2R ladder based, so they too will pass noise from the supply (no internal reference, or reference pin). ... if you get the twelve-output one, and only need nine, could it help if one were to put filter capacitor(s) on the other outputs, and set 'em all high? That would put a decoupling capacitor on the chip side of any Vcc wiring drop. Heck, you could use an AC-coupled amp to do an active filter...