Datasheet

AD7731
–41–REV. 0
SIGMA-
DELTA
MODULATOR
CLOCK
GENERATION
AD7731
SERIAL INTERFACE
AND CONTROL LOGIC
REGISTER BANK
DIGITAL
FILTER
SIGMA-DELTA A/D
CONVERTER
BUFFER
PGA
STANDBY
SYNC
MCLK IN
MCLK OUT
SCLK
CS
DIN
DOUT
RESETRDYPOL
DGND
+5V
SWITCHING
MATRIX
100nA
AGND
100nA
AV
DD
AIN1
AIN2
AIN3
AIN4
AIN5
AIN6
AGND
REF IN (–)
REF IN (+)
AD780
+5V
V
OUT
GND
+V
IN
AV
DD
DV
DD
CC
R
R
THERMOCOUPLE
JUNCTION
Figure 23. Temperature Measurement Using the AD7731
SIGMA-
DELTA
MODULATOR
CLOCK
GENERATION
AD7731
SERIAL INTERFACE
AND CONTROL LOGIC
REGISTER BANK
DIGITAL
FILTER
SIGMA-DELTA A/D
CONVERTER
BUFFER
PGA
STANDBY
SYNC
MCLK IN
MCLK OUT
SCLKCSDINDOUT
RESET
RDY
POL
DGND
+5V
SWITCHING
MATRIX
100nA
AGND
100nA
AV
DD
AIN1
AIN2
AGND
REF IN (–)
REF IN (+)
AV
DD
DV
DD
400mA
R1
6.25k
R
L1
R
L2
R
L3
R
L4
RTD
R2
3k
Figure 24. RTD Measurement Using the AD7731
REV. A