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ADVANCED COMMUNICATIONS & SENSING
USER GUIDE
SX8724SEVK
Evaluation Kit for SX8724S Data Acquisition System
ACS - Revision 1.0 May 2011
© Semtech Corp.
13.4
ZoomingADC controls
The ZoomingADC control sections allows the user to configure the acquisition chain of the SX8724S by
selecting the control corresponding to the desired mode. Note that the settings are applied to the device
registers as soon as the control is changed.
The representation picture on the top gives an indication of the settings applied to the ZoomingADC.
13.4.1 Reference selection control
This control allows to choose the reference voltage of the acquisition chain. This can be the internally
generated V
REF
with a nominal value of 1.22V or V
BATT
(2.4V to 5.5V).
When the control selects V
REF
, it can also be selected combined with a GPIO to provide a reference voltage
from GPIO. See
for details.
13.4.2 Inputs controls
The controls in the group named “Inputs” lets the user choose which inputs and which reference pins will be
used to make the measurement. On this group of controls the user may also choose if the inputs are “Single-
ended” or “Differential” as well as choosing which of the inputs is used as “Positive” or “Negative” input.
13.4.3 PGA controls
The group of controls named “PGA” lets the user control the gain, offset and enabling disabling each PGA
individually.
The user has also the possibility to control the PGAs biasing current ratio.
Figure 20. ZoomingADC Control Sections
