SX8722I070LF SEMTECH [Semtech Corporation], SX8722I070LF Datasheet - Page 62

• Manufacturer Part Number: SX8722I070LF
• Description: High gain acquisition for sensor interface
• Manufacturer: SEMTECH [Semtech Corporation]

where the total PGA gain is defined as:
and the total PGA offset is:
12.8. ADC Characteristics
The main performance characteristics of the ADC (resolution, conversion time, etc.) are determined by three programmable
parameters:
The setting of these parameters and the resulting performances are described hereafter.
12.8.1. Conversion Sequence
A conversion is started each time the bit START or the bit DEF is set. As depicted in Figure 3, a complete analog-to-digital
conversion sequence is made of a set of N
elementary conversion is made of (OSR+1) sampling periods TS=1/f
The result is the mean of the elementary conversion results. An important feature is that the elementary conversions are
alternatively performed with the offset of the internal amplifiers contributing in one direction and the other to the output code.
Thus, converter internal offset is eliminated if at least two elementary sequences are performed (i.e. if N
additional clock cycles are also required to initiate and end the conversion properly.
ACS - Revision 4.2
©2008 Semtech Corp.
ADVANCED COMMUNICATIONS & SENSING
Oversampling frequency f
over-sampling ratio OSR, and
number of elementary conversions N
GDoff
GD
T
TOT
ELCONV
TOT
=
GDoff
=
(Eq. 10)
(Eq. 11)
(Eq. 12)
=
GD
(
OSR
3
3
⋅
S
GD
+
,
GD
+
October 2008
1
2
/ )
⋅
3
GD
⋅
f
GDoff
S
1
ELCONV.
ELCONV
2
elementary incremental conversions and a final quantization step. Each
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High gain acquisition for sensor interface
, i.e.:
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ELCONV
= 2). A few