ADS7844
4
SBAS100A
www.ti.com
PIN CONFIGURATION
Top View
PIN DESCRIPTIONS
PIN NAME DESCRIPTION
1 CH0 Analog Input Channel 0.
2 CH1 Analog Input Channel 1.
3 CH2 Analog Input Channel 2.
4 CH3 Analog Input Channel 3.
5 CH4 Analog Input Channel 4.
6 CH5 Analog Input Channel 5.
7 CH6 Analog Input Channel 6.
8 CH7 Analog Input Channel 7.
9 COM
Ground reference for analog inputs. Sets zero code
voltage in single ended mode. Connect this pin to ground
or ground reference point.
10 SHDN Shutdown. When LOW, the device enters a very low
power shutdown mode.
11 V
REF
Voltage Reference Input. See Specification Table for
ranges.
12 +V
CC
Power Supply, 2.7V to 5V.
13 GND Ground
14 GND Ground
15 D
OUT
Serial Data Output. Data is shifted on the falling edge of
D
CLK
. This output is high impedance when
CS is high.
16 BUSY Busy Output. Busy goes low when the DIN control bits
are being read and also when the device is converting.
The Output is high impedance when CS is High.
17 D
IN
Serial Data Input. If CS is LOW, data is latched on rising
edge of D
CLK
.
18 CS Chip Select Input. Active LOW. Data will not be clocked
into D
IN
unless CS is low. When CS is high D
OUT
is high
impedance.
19 CLK External Clock Input. The clock speed determines the
conversion rate by the equation f
CLK
= 16 • f
SAMPLE
.
20 +V
CC
Power Supply
1
2
3
4
5
6
7
8
9
10
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
COM
SHDN
+V
CC
D
CLK
CS
D
IN
BUSY
D
OUT
GND
GND
+V
CC
V
REF
20
19
18
17
16
15
14
13
12
11
ADS7844
MINIMUM
RELATIVE MAXIMUM SPECIFIED
ACCURACY GAIN ERROR TEMPERATURE PACKAGE ORDERING TRANSPORT
PRODUCT (LSB) (LSB) RANGE PACKAGE-LEAD DESIGNATOR NUMBER MEDIA, QUANTITY
ADS7844E ±2 ±4 –40°C to +85°C QSOP-20 DBQ ADS7844E Rails, 56
" " " " " " ADS7844E/2K5 Tape and Reel, 2500
ADS7844N " " " SSOP-20 DB ADS7844N Rails, 68
" " " " " " ADS7844N/1K Tape and Reel,1000
ADS7844EB ±1 ±3 –40°C to +85°C QSOP-20 DBQ ADS7844EB Rails, 56
" " " " " " ADS7844EB/2K5 Tape and Reel, 2500
ADS7844NB " " " SSOP-20 DB ADS7844NB Rails, 68
" " " " " " ADS7844NB/1K Tape and Reel, 1000
NOTES: (1) For the most current package and ordering information, see the Package Option Addendum at the end of this data sheet.
PACKAGE/ORDERING INFORMATION
(1)
ABSOLUTE MAXIMUM RATINGS
(1)
+V
CC
to GND ........................................................................ –0.3V to +6V
Analog Inputs to GND ............................................ –0.3V to +V
CC
+ 0.3V
Digital Inputs to GND ........................................................... –0.3V to +6V
Power Dissipation .......................................................................... 250mW
Maximum Junction Temperature ................................................... +150°C
Operating Temperature Range ........................................–40°C to +85°C
Storage Temperature Range .........................................–65°C to +150°C
Lead Temperature (soldering, 10s)............................................... +300°C
NOTE: (1) Stresses above those listed under “Absolute Maximum Ratings”
may cause permanent damage to the device. Exposure to absolute maximum
conditions for extended periods may affect device reliability.
ELECTROSTATIC
DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Texas Instru-
ments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and
installation procedures can cause damage.
ESD damage can range from subtle performance degradation to
complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes
could cause the device not to meet its published specifications.
