XE8000EV110 Semtech, XE8000EV110 Datasheet - Page 124

• Manufacturer Part Number: XE8000EV110
• Description: EVAL BOARD FOR XE8802AMI035LF
• Manufacturer: Semtech
• Type: MCUr

Specifications of XE8000EV110

• Contents: Fully Assembled Evaluation Board
• For Use With/related Products: XE88LC02MI035
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

17.7.2
The word FIN[1:0] is used to select the sampling frequency f
RC-based frequency f
information on oscillators and their control can be found in the clock block documentation.
17.7.3
The over-sampling ratio (OSR) defines the number of integration cycles per elementary conversion. Its value is set
with the word SET_OSR[2:0] in power of 2 steps (see Table 17-20) given by:
© Semtech 2006
OSR
Sampling Frequency
Over-Sampling Ratio
=
2
Conversion index
3
+
SET_OSR[2
Init
RCEXT
Table 17-19. Sampling frequency settings (f
Offset
Conversion
Elementary
:
can be chosen. For FIN = "11", sampling frequency is about 8kHz. Additional
0]
(RegAcCfg0[4:2])
1
+
Figure 17-5. Analog-to-digital conversion sequence
SET_OSR[2:0]
FIN[1:0]
Table 17-20. Over-sampling ratio settings
T
(-)
ELCONV
000
001
010
011
100
101
110
111
00
01
10
11
Conversion
Elementary
XE8802 Sensing Machine Data Acquisition MCU
= (OSR+1)/f
2
-
T
S
CONV
17-12
Over-Sampling Ratio
Sampling Frequency f
XE8801/05
1/32⋅f
Conversion
Elementary
1/4⋅f
1/8⋅f
∼8kHz
N
with ZoomingADC™ and LCD driver
ELCONV
OSR (-)
1024
128
256
512
RC
RC
S
16
32
64
+
RC
8
(Table 17-19). Three sub-multiples of the internal
- 1
RC
(Eq. 13)
= RC-based frequency)
Elementary
Conversion
N
1/16⋅f
1/64⋅f
ELCONV
1/8⋅f
-
∼4kHz
S
RCEXT
XE8802
RCEXT
RCEXT
(Hz)
End
Conversion
Result
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