EVAL-AD7706EBZ Analog Devices Inc, EVAL-AD7706EBZ Datasheet - Page 40
EVAL-AD7706EBZ
Manufacturer Part Number
EVAL-AD7706EBZ
Description
BOARD EVALUATION FOR AD7706
Manufacturer
Analog Devices Inc
Specifications of EVAL-AD7706EBZ
Number Of Adc's
1
Number Of Bits
16
Sampling Rate (per Second)
500
Data Interface
Serial
Inputs Per Adc
3 Differential
Input Range
0 ~ 5.25 V
Power (typ) @ Conditions
6.5mW @ 500SPS
Voltage Supply Source
Single Supply
Operating Temperature
-40°C ~ 85°C
Utilized Ic / Part
AD7706
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
AD7705/AD7706
SMART TRANSMITTERS
Another application where the low power, single-supply, 3-wire
interface capabilities of the AD7705/AD7706 are beneficial is in
smart transmitters. Figure 28 shows a block diagram of a smart
transmitter using the AD7705. Because a smart transmitter
must operate from a 4 to 20 mA loop, tolerances in the loop
SENSORS
RTD
mV
TC
Ω
V
DD
AD7705
GND
ISOLATED GROUND
REF IN
ISOLATED SUPPLY
MCLK OUT
MCLK IN
4.7μF
100kΩ
ISOLATION
Figure 28. Smart Transmitter Using the AD7705
BARRIER
Rev. C | Page 40 of 44
MICROCONTROLLER UNIT
•PID
•RANGE SETTING
•CALIBRATION
•LINEARIZATION
•OUTPUT CONTROL
•SERIAL COMMUNICATION
•HART PROTOCOL
V
CC
COM
MAIN TRANSMITTER ASSEMBLY
mean that the current available to power the transmitter can be
as low as 3.5 mA. The AD7705 consumes only 320 μA, leaving
at least 3 mA available for the rest of the transmitter. The
AD7705, with its dual-input channel, is ideally suited for
systems requiring an auxiliary channel whose measured
variable is used to correct that of the primary channel.
4.7μF
0.01μF
V
REF OUT1
REF OUT2
REF IN
C1 C2 C3
CC
0.01μF
2.2μF
AD421
0.1μF
0.0033μF
BOOST
COMP
DRIVE
LOOP
COM
RTN
DN25D
1000pF
0.01μF
1kΩ
4mA
TO
20mA