Trenz Electronic GmbH Support Forum

Archived Boards and Threads => Archived Boards => FAQ Wireless Products => Topic started by: Horsa on June 23, 2010, 09:31:49 AM

Title: [Telit] Input impedance of the ADC(s) of Telit modules.
Post by: Horsa on June 23, 2010, 09:31:49 AM
Q: What is the input impedance of the ADC(s) (analog-to-digital converter(s)) of Telit modules?

It is not easy to answer because the ADC input is controlled by an electronic switch and terminated by a capacitor, which value is not declared by Infineon.
This pin it is also used for internal measures with low impedance ( < 1kohm).
When AT#ADC is used, the internal ADC is switched to the pin. Therefore we suggest the users to use a low impedance too, otherwise it is possible that the voltage measured will be about 10 / 20 mV less than the real value.