CS5520-BSZ Cirrus Logic Inc, CS5520-BSZ Datasheet - Page 36

• Manufacturer Part Number: CS5520-BSZ
• Description: IC ADC 20BIT BRIDGE TRAS 24-SOIC
• Manufacturer: Cirrus Logic Inc

Specifications of CS5520-BSZ

• Number Of Bits: 20
• Sampling Rate (per Second): 60
• Data Interface: Serial
• Number Of Converters: 2
• Power Dissipation (max): 37.5mW
• Voltage Supply Source: Analog and Digital, Dual ±
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 24-SOIC (0.300", 7.50mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 598-1102-5

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must be removed from between the +VREF and
-VREF pins. It may be desirable to also remove
R5, R7, C16, and C17 in some applications.
Calibrating the A/D Converter
As explained in the CS5516/CS5520 data sheet,
the order in which the calibration steps are per-
formed are important. If one chooses to use the
non-ratiometric calibration capabilities of the
converter, the non-ratiometric errors of the
VREF and AIN channels should be calibrated
first. The non-ratiometric calibration steps can
be performed at the same time. Before the non-
ratiometric offset calibration is initiated, the
bridge should be grounded. This can be achieved
on the evaluation board by moving the two
jumpers at the output of the MIC4428 driver to
the GND position (see Figure 1). The converter
is then instructed via the configuration register
bits to perform the non-ratiometric calibration
steps. Once the non-ratiometric calibrations are
completed, jumpers at the output of the
36
AGND
+5V
-5V
Z1
Z2
+
+
47 F
47 F
C1
C3
Figure 6. Using Off-board Voltage Reference
0.1 F
0.1 F
C4
C2
+5VA
-5VA
MIC4428 driver should be returned to the EXC
position.
After the non-ratiometric calibration steps are
performed, the AIN ratiometric offset is then
calibrated. With "zero weight" on the load cell,
the converter is instructed via the configuration
register to perform the AIN ratiometric offset
calibration step. Finally, with "full scale weight"
on the load cell, the converter is instructed to
perform the gain calibration step.
The converter is then ready to perform conver-
sions.
Software
The evaluation board comes with software and a
RS-232 cable to interface the board to a RS-232
port of a PC-compatible computer. The software
diskette contains a README.TXT file which
explains its operation.
DGND
+5
Z3
CDB5516/CDB5520
+
47 F
C5
0.1 F
C6
DS74DB4
DS74DB3
+5VD