AnsweredAssumed Answered

Converting values on ADC input port with lookup table?

Question asked by Robin on Jun 16, 2010
Latest reply on Jul 13, 2010 by BrettG

I am currently using the signal on one ADC input port to control an index selectable multiband filter with 16 rows (see enclosed jpeg-file).

The signal on the ADC input port is generated by a 4-bit R2R-network. Obviously the R2R-network doesn't deliver the right values that are expected by the filter cell (e.g. it delivers a maximum voltage of 2.6 volts instead of 3 volts for full-scale of the ADC).

Is there any chance to convert the 16 values coming from the R2R-network with a lookup table? I have already tried several things, but nothing's seem to work.

Another application for such a conversion would be to convert the signal from a linear potentiometer into a logarithmic signal to control a SW volume cell.

I have already read the AN-951, where something similar is mentioned, but I have no clue to make it functionable for my project.


Any help is highly appreciated. Thanks in advance



P.S.: I use the ADAU1701