Change analog bandwidth of slow ADCs / XADC external inputs
Posted: Mon Nov 25, 2019 2:34 pm
Hi,
I am starting to hit the limits of the slow ADC bandwidth on the STEMLab 125-14. Looking at page5 of the schematics, I understand that there is an analog low-pass primarily formed by R85 and C101, yielding a cutoff frequency of
1/(2*pi*220 pF*30kOhm) = 24 kHz. I would like to increase the analog bandwidth, for example by bypassing R85 by a short, because the "slow" ADCs can be sampled at 1 MSPS. My problem is that I do not know which resistor on the board R85 (and for the other inputs R86-R88), and possibly the other related components, correspond to.
Can anyone help me out here?
Thanks a million! Leo
I am starting to hit the limits of the slow ADC bandwidth on the STEMLab 125-14. Looking at page5 of the schematics, I understand that there is an analog low-pass primarily formed by R85 and C101, yielding a cutoff frequency of
1/(2*pi*220 pF*30kOhm) = 24 kHz. I would like to increase the analog bandwidth, for example by bypassing R85 by a short, because the "slow" ADCs can be sampled at 1 MSPS. My problem is that I do not know which resistor on the board R85 (and for the other inputs R86-R88), and possibly the other related components, correspond to.
Can anyone help me out here?
Thanks a million! Leo