ADM13307-5ARZ internal resistor value

Question

Hello, 
 I have a question about internal resistor value of R1 and R2. 
 I will pull-up SENSER1 pin to 3.3V by 10k ohms. I would like to check the impact of the external resistor value (10k ohms). Could you please advise me the resistor value of R1 and R2? 
 Best regards, 
 Akira

Fil · Accepted Answer

Hi Okasaka-san, 
 This is what design had to say: 
 Confirming the following resistor values (roughly in line with estimate based on the data sheet specs): 
 R1 = 955kohms 
 R2 = 246kohms 
 The ratio of these two resistors will stay constant, and expected to match to within better than 1%. 
 The absolute values of the resistors will change with temperature. The resistor values will decrease as temp goes up, maybe by as much as 15% from 25degC to 85degC. 
 The absolute value of the resistors will also change from part to part, so an allowance for +/-25% at least. 
 
 If the user is adding a 10kohm resistor externally, the impact is that it will move the nominal threshold up by ~1%. Allowing for this being in the range of 0.5% to 1.5% though, to account for the mismatch of this external resistor to the absolute value of the internal resistors.)

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ADM13307-5ARZ internal resistor value