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# KCC's quizzes AQQ260 about a technical article correction

1. Quote of the week: "No man goes before his time - unless the boss leaves early" - Groucho Marx

2. New quiz AQQ260 about a technical article correction

One (external) reader has noticed a mistake or imprecision in an ADI technical article:

The “faulty” section is displayed here below (note the BU is checking this for a coming quick update):

Questions:

1. What and where is the error or imprecision?
2. How would you correct it?

Good luck! And try to be among the firsts!

Kuo-Chang

P.S. Don't hesitate to share those weekly quizzes in EZ to colleagues or friends!

Parents
• If Tint=R*C, then ref time is Tref=Tint*Vref/Vin.
Time is not proportional but inversely proportional to Vin.

(And maybe a small note, the voltage is not integrated, but here the current is integrated, which depends on Vin)

• If Tint=R*C, then ref time is Tref=Tint*Vref/Vin.
Time is not proportional but inversely proportional to Vin.

(And maybe a small note, the voltage is not integrated, but here the current is integrated, which depends on Vin)

Children
• Sure  , you have found the main mistake which is Tint is not proportional to Vin. Then you can say, as corrective action, to correct the text, it's inversely proportional to Vin. But our problem is not solved: as it is now, the circuit cannot work as a single-slope ADC! Something must be corrected in the circuit as well (and not only the text)!

• OK, so, if I am considering an ADC with periodic sampling, then the reset (discharging) switch of the capacitor is missing in the circuit. And the frequency counter at the output of comparator. Do you mean this?

• Thanks  . I agree a counter block has to follow that integrator front end. But having the time delay inversely proporptional to Vin cannot give you the DAC function, regradless of the counter you put after it... A more fundamental change must be done on the integrator first...

• As mentioned in previous answers, Vin and Vref must be interchanged.

• YES! Congratulations!