Post Go back to editing

1701 division block

Hi all

I thought I understood the Q number code system but I did the following test

Using 2 DC generators with 0.1 and 0.01 outputs in 5.23 format and the division block the read back output is 1.6?

Can anyone shed any light on this?

1/0.7 = 1.41 and 1/0.07 = 14.1 so some of the numbers work as they should.

John


Parents
  •      Hi John,

         I hope your design has worked out to your satisfaction.

         Recently the ADI programmers came up with a log lookup table for the ADAU1701.  In effect this exposes the -1701's log function (which was always inside) to us users.  In turn, this made me think if it were possible to perform real-time division via subtracting logs of inputs, as shown below.  Unfortunately the tables' linear interpolation, while fine for level meters and such, is not up to the

    mathematical precision this task requires.  I got only approximate answers.  The main reason for my posting this is to save someone else from wasting time on trying it.

         Best regards,

         Bob

Reply
  •      Hi John,

         I hope your design has worked out to your satisfaction.

         Recently the ADI programmers came up with a log lookup table for the ADAU1701.  In effect this exposes the -1701's log function (which was always inside) to us users.  In turn, this made me think if it were possible to perform real-time division via subtracting logs of inputs, as shown below.  Unfortunately the tables' linear interpolation, while fine for level meters and such, is not up to the

    mathematical precision this task requires.  I got only approximate answers.  The main reason for my posting this is to save someone else from wasting time on trying it.

         Best regards,

         Bob

Children
No Data