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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.
13.4.8 Mode
Charge pump force ON and OFF
allows to force ON or OFF the internal voltage multiplier to avoid
conversion interruptions due to the pump switching off and on when the V
BATT
supply is near 3V. Force
ON takes priority to Force OFF.
VREF chopping control
allow chopping of the 1.22V internal bandgap reference. This helps to eliminate
bandgap related internal offset voltage and 1/f noise. The bandgap chop state may be forced
High
or
Low
,
or may be set to toggle during conversion at either the same rate or half the rate of the Elementary
Conversion.
Bandgap on D0 pin
, outputs the SX8724S internal V
REF
on D0 pin. This allows external monitoring of the
internal bandgap reference or the ability to use an external reference input for the ADC, or the option to
filter the internal V
REF
output before feeding back as V
REF,ADC
input.
VREF on D1 pin
allows to select D1 pin as reference voltage for the acquisition chain. As described in
, D1 can input a V
REF
. When using an external V
REF,ADC
input, it may have any value
between 0V and V
BATT
.
