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Is there an equation for calculating the trim voltage on the ADR440 series voltage references?

Thread Summary

The user inquired about trimming the output voltage of the ADR440 series voltage references by ±0.5% using resistors instead of a potentiometer. The final answer directed the user to Figure 37 of the datasheet for the optimal trim configuration, noting that internal resistor values can vary by 10% to 20%. The accompanying answer suggested measuring the potentiometer values after trimming and replacing it with fixed resistors for a more compact and stable solution.
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Category: Hardware
Product Number: ADR440

The datasheet shows a suggested circuit for trimming the output voltage of the ADR440 series voltage references by ±0.5%. The circuit uses a potentiometer. The datasheet doesn't give any kind of equation for how the trim works.

I am wondering if there is some way to, say, use a precision benchtop multimeter, measure the error, and then calculate the value of resistors to populate to trim/calibrate the output. While a pot is easy to use, it takes up valuable circuit space and can be susceptible to vibration.

Edit Notes

I fixed the title from regulators to voltage references
[edited by: fgmdfbdfzdvdvdz at 1:36 AM (GMT -4) on 16 Oct 2022]