TPS1200-Q1: ISCP Set Point Accuracy Calculation in Calculator Tool

Jacob Wyrick

Part Number: TPS1200-Q1

Tool/software:

Hi team - Cell F23 is calculating the accuracy of the ISCP set point. The tolerance of the RSNS and RISCP resistors make sense (F19 / F22), but where is the 13.3% coming from?

I can't find reference to a 13.3% error in the datasheet and that figure appears to be hard coded. Example values below for reference:

Thanks,

Jacob

6 months ago

0 Sarah Raines 6 months ago

TI__Genius 9700 points

Hi Jacob,

Im checking on this now.

Thanks,

Sarah

0 Sarah Raines 6 months ago in reply to Sarah Raines

TI__Genius 9700 points

Hi Jacob,

The 13% is intended to represent the SCP accuracy, which is actually 20%. This is a typo. Ill update the calculator online before EOW.

Thanks,

Sarah

0 Jacob Wyrick 6 months ago in reply to Sarah Raines

TI__Expert 8575 points

Thank you Sarah! To confirm, is that SCP accuracy called out in the datasheet? Which specification is it referenced to?

0 Sarah Raines 6 months ago in reply to Jacob Wyrick

TI__Genius 9700 points

Hi Jacob,

Yes its from the V_SCP threshold. The 20% comes from the values in the table. (75 mV + 20% = 90 mV)

Thanks,

Sarah

0 Jacob Wyrick 6 months ago in reply to Sarah Raines

TI__Expert 8575 points

Thanks Sarah. One final question. A few rows down the tolerance is 20mV +/- 5mV which is closer to 25%. Is there a reason we're using 20% as opposed to 25%?

Does the calculator account for which R(iscp) is being selected to better estimate which tolerance should be used?

0 Sarah Raines 6 months ago in reply to Jacob Wyrick

TI__Genius 9700 points

Hi Jacob,

The assumption here is that most people are designing RISCP values > 10kohm. The calculator does not account for this specifically its a generalization.

Thank you,

Sarah

+1 Sarah Raines 5 months ago in reply to Sarah Raines

TI__Genius 9700 points

Hi Jacob,

I have published the latest revision of the calculator as Version 2 with the above change.

Thanks,

Sarah

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TPS1200-Q1: ISCP Set Point Accuracy Calculation in Calculator Tool