Voltage or Currents for continuous time a/d converters ???

[svensl]

I was wondering why some people use current-based integrators and some voltage-based integrators for CT Sigma Delta A/D converters? What are some advantages of using currents over voltages? Are currents easier to handle? I would appreciate if someone could share their thoughts.
Thanks.

 

[ocarnu]

Re: Voltage or Currents for continuous time a/d converters ?

Hi,
The current mode operation is potentially faster, using open loop OTA. The problem with it is the linearity (again, open loop, no feedback). This is why CT delta sigma with OTA are limited to 10-12 bits linearity.