Datasheet
AD7721
REV. A
–5–
ABSOLUTE MAXIMUM RATINGS
1
(T
A
= +25°C unless otherwise stated)
DV
DD
to DGND . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +7 V
AV
DD
to AGND . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +7 V
AV
DD
to DV
DD
. . . . . . . . . . . . . . . . . . . . . . –0.3 V to +0.3 V
AGND to DGND . . . . . . . . . . . . . . . . . . . . –0.3 V to +0.3 V
Digital Input Voltage to DGND . . . –0.3 V to DV
DD
+ 0.3 V
Analog Input Voltage to AGND . . . . –0.3 V to AV
DD
+ 0.3 V
Input Current to Any Pin Except Supplies
2
. . . . . . . ±10 mA
Operating Temperature Range
Industrial (A Version) . . . . . . . . . . . . . . . . . –40°C to +85°C
Extended (S Version) . . . . . . . . . . . . . . . . –55°C to +125°C
Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C
Maximum Junction Temperature . . . . . . . . . . . . . . . +150°C
Plastic Package
θ
JA
Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 74°C/W
Lead Temperature, Soldering (10 sec) . . . . . . . . . . +260°C
Cerdip Package
θ
JA
Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 51°C/W
Lead Temperature, Soldering (10 sec) . . . . . . . . . . +300°C
SOIC Package
θ
JA
Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 72°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . +215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . +220°C
NOTES
1
Stresses above those listed under Absolute Maximum Ratings may cause perma-
nent damage to the device. This is a stress rating only; functional operation of the
device at these or any other conditions above those listed in the operational
sections of this specification is not implied. Exposure to absolute maximum
rating conditions for extended periods may affect device reliability.
2
Transient currents of up to 100 mA will not cause SCR latchup.
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although this device features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.
ORDERING GUIDE
Model Temperature Range Package Option*
AD7721AN –40°C to +85°C N-28
AD7721AR –40°C to +85°C R-28
AD7721SQ –55°C to +125°C Q-28
*N = Plastic DIP; R = 0.3" Small Outline IC (SOIC); Q = Cerdip.
PIN CONFIGURATION
14
13
12
11
17
16
15
20
19
18
10
9
8
1
2
3
4
7
6
5
TOP VIEW
(Not to Scale)
28
27
26
25
24
23
22
21
AD7721
SCLK/DB7
DVAL/SYNC
WR
RD
DB6
DB8
DB9
RFS
/DB10
VIN1
VIN2
AGND
SDATA/DB11
DGND
DSUBST
DGND
STBY/DB0
DV
DD
AV
DD
AGND
REFIN
CAL/DB1
UNI
/DB2
DB3
DB4
CS
SYNC/DB5
DRDY
CLK
WARNING!
ESD SENSITIVE DEVICE