ADXL001 performance at 1000pF load capacitance

Document created by analog-archivist Employee on Feb 23, 2016
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For improved EMI performance, it is recommended in the datasheet to connect to
the output of ADXL001 a 1000 pF capacitor.

Does ADXL001 provide a 22 kHz bandwidth with this capacitor or is the bandwidth
independent of the load capacitor value?

Is it possible to get a Table of correspondence (or formula or Routput) to
estimate Frequency response (-3dB) and EMI under different capacitor's value as
was for ADXL327, for example?


The output of the ADXL001 is different from the ADXL327.
The ADXL327 has an internal 32kohm resistor at the output of the part, which
when paired with an external resistor, creates a low pass filter which limits
the bandwidth of the part.

The ADXL001 has a much lower output impedance (~100 ohms). In theory, the
principle is the same that the output R and external C create a LPF where
fc=1/(2*pi*R*C). However, because of the low output impedance, you would need
larger capacitor values which can destabilize and overload the
output, so not the best idea. 

I would suggest having a separate filter stage.