sx8724s Semtech Corporation, sx8724s Datasheet - Page 30

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

Revision 1.0
© Semtech
In "continuous-time" mode, the input signal is repeatedly converted into digital. After a conversion is finished, a new
one is automatically initiated. The new value is then written in the result register, and the corresponding internal
trigger pulse is generated. This operation is sketched in
In the "on-request" mode, the internal behavior of the converter is the same as in the "continuous-time" mode, but the
conversion is initiated on user request (with the Start bit). As shown in
7.7.8 Output Code Format
The ADC output code is a 16-bit word in two's complement format (see
the output code is saturated to the closest full-scale value (i.e. 0x7FFF or 0x8000). For resolutions smaller than 16 bits,
the non-significant bits are forced to the values shown in
Recalling
ADVANCED COMMUNICATIONS & SENSING
Equation 10, page
Internal trig
Output code RegACOut[15:0]
Busy
Ready
Internal trig
START Request
Output code RegACOut[15:0]
Busy
Ready
OUT
February 2011
ADC
24, this can be rewritten as:
=
2
16
Figure 15. ADC “Continuous-Time” Operation
⋅
V
V
Figure 16. ADC “On-Request” Operation
OUT
REF
IN
⋅
⎛
⎜ ⎜
⎝
ADC
GD
1/fs
TOT
=
Equation 18
Equation 19
Page 30
2
−
16
Figure
GDoff
Table
⋅
V
V
IN
REF
,
ADC
TOT
15. The conversion time in this case is defined as T
Tconv
Tconv
19. The output code, expressed in LSBs, corresponds to:
ZoomingADC for sensing data acquisition
⋅
⋅
S
OSR
⋅
OSR
V
Figure
Table
V
REF
IN
+
⎞
⋅ ⎟ ⎟
⎠
1
18). For input voltages outside the range,
16, the conversion time is also T
OSR
OSR
+
1
[
LSB
]
SX8724S
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DATASHEET
CONV
CONV
.
.