Dear Specialists,
My customer is considering INA138 and has a question.
Could I get advice datasheet of 8.2.2 output filter for him.
---Question
According to the datasheet P.12 8.2.2 output filter, it consists of capacitor and resistor in parallel.
It is unusual.
Could you please advise the reason?
Usually Low Pass Filter consists resistor in series and capacitor connects between output and gnd.
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I appreciate your great help.
Best regards,
Shinichi
Dear Shinichi,
Your customer is correct that the typical low pass filter is a resistor in series, but due to the current output nature of the part, the output filter here is done with the load resistor used to set the gain. This is done by placing a load capacitor in parallel to achieve the desired frequency for the filter. There is an in depth explanation of this in the following section, 8.2.2.2 of the datasheet, as well as typical curves for the roll off in 8.2.2.3.
Let me know if you need any more clarification on this.
