DAC11001A: Closed-Loop Control System Design

Marko Havu

Part Number: DAC11001A

In SLAA885 Figure 1, there is a feed-forward DAC in the digital control loop. Does it change the gain of the output amplifier in the analog control loop? Is this a common design in such control-loop applications? Can you point me towards any literature?

over 4 years ago

0 Paul_Frost over 4 years ago

TI__Guru 52683 points

Hi Marko,

My colleague Akhilesh can help you with this when he gets back to the office. For reference, here is the diagram you are refering to.

0 Uttam Sahu over 4 years ago in reply to Paul_Frost

TI__Genius 14220 points

Hi Marko,

Thank you for your interest in our products and welcome to E2E. The feed-forward path is mainly used for coarse control and the main-control path is used for fine control. This way the entire resolution of the main-control path is used for regulating the output within a small range. This approach is used to achieve fast-settling, precision, and smaller overshoot. The feed-forward DAC output sums up with the main-controller output.

Please find below some related third-party articles describing various applications of feed-forward control:

https://pdfs.semanticscholar.org/dcfe/52f8cfd1361f9ab9e93cabcb4db0bb5d41d5.pdf

http://www.bgu.ac.il/chem_eng/pages/Courses/oren%20courses/Chapter_9.pdf

https://web.archive.org/web/20110927022329/http://www.isa.org/Content/ContentGroups/Motion_Control2/Departments1/Motion_Fundamentals/200227/20020421.pdf

https://en.wikipedia.org/wiki/Feed_forward_(control)

If you could let us know about your application, we could suggest a more specific solution.

Hope that answers your question.

Regards,

Uttam Sahu

Systems Engineer, Precision DAC