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previous: GVB Been dare. Dun Dat. I have heaps o... -- 9/4/1998 12:11 AM

Re: Digital Pots......Help!

9/4/1998 7:25 AM
Don Symes	Re: Digital Pots......Help! Vishay/Dale, Rohm, and CTS used to make (and probably still do make) R-2R resistor ladder networks that would form the heart of a DAC. Controlling the FETs (jFETs?) is going to be the trick - getting them turned good and ON or good and OFF as required. I'm assuming you're going to have some kind of CPU in the thing, so you can use that to convert from your control's need to be logarithmic to the DACs linear response. Hey, maybe they make LOGDAC resistor nets...

9/4/1998 7:25 AM

Don Symes

Re: Digital Pots......Help!

Vishay/Dale, Rohm, and CTS used to make (and probably still do make) R-2R resistor ladder networks that would form the heart of a DAC. Controlling the FETs (jFETs?) is going to be the trick - getting them turned good and ON or good and OFF as required. I'm assuming you're going to have some kind of CPU in the thing, so you can use that to convert from your control's need to be logarithmic to the DACs linear response.

Hey, maybe they make LOGDAC resistor nets...