Author Topic: RMS-DC converter LT1968 doesn't work properly  (Read 756 times)

0 Members and 1 Guest are viewing this topic.

Offline georgfour

  • Newbie
  • Posts: 1
  • Country: ru
RMS-DC converter LT1968 doesn't work properly
« on: May 07, 2016, 05:49:37 pm »
Hello!
I faced with problem - RMS-DC converter LT1968 doesn't work properly as it should.
I have scheme that is attached below.
I connect input of J3 to 1kHz meandr with peak-to-peak 2.72V  and switch on first voltage divider with SW1 and see weak 75mv at the output of LT1968 :(
At IN1 input i have properly 1.32V peak-to-peak signal that is raised at 2.5 voltage with help of divider at IN2 input.
If I switch on SW2 (and switch off another two) I get 51mv.
If I switch on SW3 (and switch off another two) I get 37mv.
If I switch off all switches I get 30mv (what???).

I simulated this scheme and it works great (screenshot below).
All contact is fine and power too.

Also attach photo of pcb.
Thank you very much for help and sorry for my language.

 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf