improving accuracy of a divider circuit

[gary36]

I have to implement a function which outputs the relation y=1-(a/b), where b>a and a/b ratio varies from 0.96 to 0.999, with minimum step size of 2mV.

I have looked at analog options such ad633 and ad734. But there accuracy is poor with respect to the requirement. Is there a way to improve the divider accuracy using just analog compoenents?

 

[KlausST]

Hi,

I have to implement a function

where and how?
It coulbe be litterally anything: PC, cell phone, C code, excel, breadboard, FPGA ...
What are the input values? analog, digital, what range, what resolution?
How fast / how often do you need it to be calculated? Or what settling time do you expect?
What is the signal´s frequency range?

which outputs the relation y=1-(a/b), where b>a and a/b ratio varies from 0.96 to 0.999, with minimum step size of 2mV.

"A relation" is unitless ... it can´t be "mV".
What are you talking about?
If you want to discuss in mV then you need to give the "ratio to voltage" factor.

From the information you give: the output range will be: 0.001 ... 0.04. Is this correct?

But there accuracy is poor with respect to the requirement.

What is your accuracy requirement?
And: an accuracy error can be calibrated out. (While a precision erro can not be calibrated out .. since it varies)

Klaus

 

[danadakk]

Analog divider using OpAmp

My teacher was teaching me about analog multiplier and divider using opamp. Following is the circuit is made us write. simulate this circuit – Schematic created using CircuitLab Could some...

electronics.stackexchange.com

Simple Components Increase Precision of Analog-Division Circuit

The example analog-divider circuit presented in this article reduces the error to less than ±0.02%, based on the resolution of both DACs.

www.electronicdesign.com

https://annas-archive.org/slow_download/9212eb867da3806c5ba26c85f113ff7e/0/0

Regards, Dana.