Datasheet
f =
FILTER
ln(2)(n + 1)
2 2RCp
R =
t
ACQ
ln(2)(n + 1)2C
CHB1P
CHB1N
CHB0P
CHB0N
CHA1P
CHA1N
CHA0P
CHA0N
SDOB
BUSY
CLOCK
CS
RD
CONVST
SDI
M0
1
2
3
4
5
6
7
8
24
23
22
21
20
19
18
17
CMB
32
REFIO1
9
CMA
31
REFIO2
10
AGND
30
RGND
11
AVDD
29
AGND
12
DGND
28
AVDD
13
DVDD
27
NC
14
NC
26
NC
15
SDOA
25
M1
16
ADS8363
ADS7263
ADS7223
DVDD
AVDD
REF5025
1 Fm22 Fm
AGND
DGND
DGND
Controller
Device
DVDD
1 Fm
AVDD
1 Fm
AGND
DGND
R
C
R
AGND
OPA2365
AVDD
AGND
AVDD
AGND
AVDD
R
R
C
OPA2365
ADS8363
ADS7263
ADS7223
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SBAS523B –OCTOBER 2010–REVISED JANUARY 2011
APPLICATION INFORMATION
MINIMUM CONFIGURATION EXAMPLE
Those values can be calculated using Equation 5:
An example of a minimum configuration for the
ADS8363/7263/7223 is shown in Figure 42. In this
case, the device is used in dual-channel,
fully-differential input mode with a four-wire digital
Where n = 16 as the resolution of the ADS8363
interface connected to the controller device and with
(n = 14 for ADS7263, n = 12 for ADS7223). (5)
default settings of the device after power up. Because
the internal reference is disabled upon power up (to
As a good trade-off between required minimum driver
prevent driving against an external reference if used),
bandwidth and the capacitor value, it is
an external reference source is shown in this
recommended to use a capacitor value of at least
example. To allow the use of the internal reference,
1nF.
the SDI input must be connected to the controller,
Keeping the acquisition time in mind, the resistor
allowing access to the REFDAC registers. The
value can be calculated as shown in Equation 6 for
corresponding timing diagram including the timing
each of the series resistors:
requirements are shown in Figure 43 and the Timing
Characteristics table.
The input signal for the amplifiers must fulfill the
common-mode voltage requirements of the device in
Where n = the device resolution. (6)
this configuration. The actual values of the resistors
and capacitors depend on the bandwidth and
performance requirements of the application.
Figure 42. Four-Wire Application Configuration
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