ADC noise issue

[mikeh3]

Posted on September 12, 2005 at 19:34

ADC noise issue

[mikeh3]

Posted on May 17, 2011 at 12:06

We are currently developing 10+ products with the uPSD33XX family of parts.

We have noticed significant A/D noise on all of the designs (7-10 Lsb's in most cases), this seems to be caused by some type of charge coupling from the A/D inputs (?)

Can anyone tell me what the recommended input impedence and/or input capacitance should be to minimize this problem?

We deal primarily with slow signals (10-100Hz)

We do many analog designs and are aware of most issues relating to good design practice - the microprocessors we have been using did not exhibit this problem.

Thanks in advance for any help given.

[francescatodiego2]

Posted on May 17, 2011 at 12:06

Sorry cannot help you

I am starting new project wit uPSD and analog peripheral.

I see a lot of questions about ADC peripheral and I think is not good idea use it.

Before add one external ADC to my uPSD I ask you if you have solved the ADC problems ?

thanks

[tod_02]

Posted on May 17, 2011 at 12:06

Are you putting the MCU into idle mode (via PCON) when doing your A/D read? I noticed I got much better results when doing it this way.