CS5524-AS Cirrus Logic Inc, CS5524-AS Datasheet - Page 43

• Manufacturer Part Number: CS5524-AS
• Description: A/D Converter (A-D) IC
• Manufacturer: Cirrus Logic Inc

Specifications of CS5524-AS

• Sample Rate: 606SPS
• Input Channels Per Adc: 4
• Mounting Type: Surface Mount
• No. Of Channels: 4
• Power Rating: 9mW
• Peak Reflow Compatible (260 C): No
• Supply Voltage Max: 5.25V
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

2.8 Power Supply Arrangements
The CS5521/22/23/24/28 A/D converters are de-
signed to operate from a single +5 V analog supply
and a single +5 V or +3 V digital supply. A -2.1 V
supply is usually generated from the charge pump
drive to provide power to the instrumentation am-
plifier’s NBV (negative bias voltage) pin.
Figure 21 illustrates the CS5522 connected with a
+5 V analog supply and with the external compo-
nents required for the charge pump drive. This en-
ables the CS5522 to measure ground referenced
signals with magnitudes down to ±100 mV.
Figure 22 illustrates the CS5522 connected to mea-
sure ground referenced unipolar signals of a posi-
tive polarity using the 1 V, 2.5 V, and 5 V ranges
DS317F2
LM334
Absolute
Current
Reference
Analog
Supply
+5V
Figure 21. CS5522 Configured to use on-chip charge pump to supply NBV
Cold Junction
Up to ± 100 mV Input
+5V
2.5V
V-
V+
301
R
10 k
10 k
0.1 F
499
BAV199
0.1 F
20
19
18
17
16
3
4
1
6
BAT85
VREF+
VREF-
AIN1+
AIN1-
AGND
AIN2+
AIN2-
A1
A0
VA+
NBV
2
5
1N4148
+
on the converter. For the 25 mV, 55 mV, and
100 mV ranges, the signals being digitized must
have a common mode between +1.85 to +2.65 V
(NBV = 0 V).
Although CS5521/22/23/24/28 are optimized for
the measurement of thermocouple outputs, they are
also well suited for the measurement of ratiometric
bridge transducer outputs. Figure 23 illustrates the
CS5522 connected to measure the output of a rati-
ometric differential bridge transducer while operat-
ing from a single +5 V supply. Bridge outputs may
range from 5 mV to 400 mV. See the Digital Gain
Scaling section about manipulating the gain regis-
ter to achieve optimum gain scaling.
10 F
CS5522
10
CPD
7
VD+
1N4148
0.033 F
XOUT
DGND
SCLK
SDO
14
XIN
SDI
CS
13
11
10
9
15
8
12
Logic Outputs:
A0 - A1 Switch from
VA+ to AGND.
Charge-pump network
for VD+ = 5V only and
XIN = 32.768 kHz.
32.768 ~ 100 kHz
CS5521/22/23/24/28
Interface
Optional
Source
Serial
Clock
Data
0.1 F
43