sx8724s Semtech Corporation, sx8724s Datasheet - Page 19

• Manufacturer Part Number: sx8724s
• Description: Zoomingadc For Sensing Data Acquisition
• Manufacturer: Semtech Corporation

Revision 1.0
© Semtech
7.1.3 PGA & ADC Enabling
Depending on the application objectives, the user may enable or bypass each PGA stage. This is done according to the
word Enable and the coding given in
7.2 ZoomingADC Registers
The system has a bank of eight 8-bit registers: six registers are used to configure the acquisition chain (RegAcCfg0 to
RegAcCfg5), and two registers are used to store the output code of the analog-to-digital conversion (RegAcOutMsb &
Lsb).
Table 7.
(ADC) Result
(1)
(2)
ADVANCED COMMUNICATIONS & SENSING
Register
Name
RegACOutLsb
RegACOutMs
b
RegACCfg0
Default
values:
RegACCfg1
Default value:
RegACCfg2
Default value:
RegACCfg3
Default value:
RegACCfg4
Default value:
RegACCfg5
Default value:
(r = read; w = write; rw = read & write)
Out: (r) digital output code of the analog-to-digital converter. (MSB = Out[15])
Start: (w) setting this bit triggers a single conversion (after the current one is finished). This bit always reads back 0.
Registers to Configure the Acquisition Chain (AC) and to Store the Analog-to-Digital Conversion
Bit position
7
DataReadyEn
0,
0,
0,
Pga1Gain
0,
Note 11
Note 15
Note 17
Start
Note 2
Busy
00,
11,
IbAmpAdc
February 2011
SetFs
Note 10
Note 7
6
0,
Note 18
Def
SetNelconv
01,
(RegACCfg1[3:0])
Table
Note 3
5
Enable
XXX0
XXX1
XX0X
XX1X
X0XX
X1XX
0XXX
1XXX
Table 6. ADC and PGA Enabling
6. To reduce power dissipation, the ADC can also be inactivated while idle.
00,
11,
IbAmpPga
Pga2Gain
Note 12
Note 8
Page 19
4
Out[15:8]
Out[7:0]
Note 1
0001100,
0000000,
ZoomingADC for sensing data acquisition
00000,
3
010,
Pga3Offset
PGA1 disabled
PGA2 disabled
PGA3 disabled
PGA1 enabled
PGA2 enabled
PGA3 enabled
ADC disabled
Pga3Gain
ADC enabled
SetOsr
Amux
Note 4
Block
Note 19
Note 13
Note 16
2
0000,
0000,
Pga2Offset
Enable
Note 14
Note 9
1
Continuous
0,
SX8724S
Note 5
www.semtech.com
DATASHEET
0
SampleShiftEn
0,
0,
Note 20
Vmux
Note 6