SX8723CWLTDT SEMTECH [Semtech Corporation], SX8723CWLTDT Datasheet - Page 24

• Manufacturer Part Number: SX8723CWLTDT
• Description: ZoomingADC for sensing data acquisition
• Manufacturer: SEMTECH [Semtech Corporation]

Revision 1.01
© Semtech
The output of PGA3 is also the input of the ADC. Thus, similarly to PGA2, we find that the voltage entering the ADC is
given by:
where GD
Pga3Offset[6:0].
To remain within the signal compliance of the PGA stages (no saturation), the condition:
must be verified.
To remain within the signal compliance of the ADC (no saturation), the condition:
must be verified.
ADVANCED COMMUNICATIONS & SENSING
3
and GD
OFF3
Pga3Gain bitfield
(RegACCfg3[6:0])
are respectively the gain and offset of PGA3 (in V/V). The control words are Pga3Gain[6:0] and
1000000
1111111
January 2011
...
...
V
Table 13. PGA3 Gain and Offset Settings
IN
,
ADC
127/12 (=10.58)
PGA3 Gain
GD
64/12
=
V
3
...
...
IN
[V/V]
GD
V
,
ADC
IN
3
,
⋅
V
V
<
Page 24
Equation 7
Equation 8
Equation 9
D
D
⎛
⎜
⎝
2
1
V
,
−
V
REF
2
GDoff
D
2
⎞
⎟
⎠
⎛
⎜
⎝
<
Pga3Offset bitfield
(RegACCfg4[6:0])
OSR
V
3
ZoomingADC for sensing data acquisition
OSR
BATT
⋅
2
1000001
1000010
1010000
1100000
1111111
S
−
⋅
...
...
...
V
1
REF
⎞
⎟
⎠
[
V
]
-1/12 (=-0.083)
-63/12 (=-5.25)
GD
PGA3 Offset
OFF3
-16/12
-32/12
www.semtech.com/products/
-2/12
...
...
...
[V/V]
SX8723C
DATASHEET