AD7714ARSZ-3 Analog Devices Inc, AD7714ARSZ-3 Datasheet - Page 35

• Manufacturer Part Number: AD7714ARSZ-3
• Description: 28-BIT SIGMA DELTA A/D IC
• Manufacturer: Analog Devices Inc

Specifications of AD7714ARSZ-3

• Number Of Bits: 24
• Sampling Rate (per Second): 1k
• Data Interface: DSP, MICROWIRE™, QSPI™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 7mW
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-SSOP (0.200", 5.30mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: EVAL-AD7714-3EBZ - BOARD EVALUATION FOR AD7714
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

REV. C
Temperature Measurement
Another application area for the AD7714 is in temperature
measurement. Figure 13 outlines a connection from a thermo-
couple to the AD7714. In this application, the AD7714 is oper-
ated in its buffered mode to allow large decoupling capacitors
on the front end to eliminate any noise pickup which there may
THERMOCOUPLE
+V
JUNCTION
AD780
IN
GND
+5V
V
OUT
R
R
Figure 13. Thermocouple Measurement Using the AD7714
C
REF IN (+)
REF IN (–)
C
AGND
AIN2
AIN1
AIN3
AIN4
AIN5
AIN6
AGND
AV
+5V
AV
DD
DGND
DD
1 A
1 A
BUFFER
DV
DD
BUFFER
DV
–35–
SERIAL INTERFACE
DD
A = 1–128
PGA
have been in the thermocouple leads. When the AD7714 is
operated in buffered mode, it has a reduced common-mode
range. In order to place the differential voltage from the thermo-
couple on a suitable common-mode voltage, the AIN2 input of
the AD7714 is biased up at the reference voltage, +2.5 V.
DOUT
REGISTER BANK
AUTO-ZEROED
CHARGE BALANCING A/D
MODULATOR
DIN
CONVERTER
CS
GENERATION
AD7714
CLOCK
SCLK
DIGITAL
FILTER
MCLK OUT
MCLK IN
STANDBY
SYNC
RESET
DRDY
POL
AD7714
2