Formula for ADR0x TRIM resistors

Question

I would like to use the TRIM pin with fixed resistors rather than a potentiometer to set the ADR01 output to a voltage other than nominal, within the specified adjustment range. Is there a formula to determine the appropriate resistor values? I could breadboard it then measure the potentiometer setting, but if you can provide a formula, that would be quicker and easier.

ADIApproved · Accepted Answer

Hi, 
 Please see image below for your reference. This is a representation of the device with internal resisitor value. Please take note that this is not the actual device but just a behavioral model so that we can estimate the resistor value. 
 Now, we might choose the value of R5 and R6 correctly but given the fact that these resistors has tolerances, it is highly possible that we cannot get the exact value and will show different voltage in reality. Also, the part itself has +/10 mV of error from the initial voltage so we should expect that additional error will be added to the resistor divider. That is why it is highly recommended to use potentiometer to adjust the output voltage to the desired output. 
 I have a question, why do you need 10. 03 V reference or on what application are you using this part? 
 
 Regards, 
 Phil)

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Formula for ADR0x TRIM resistors