ꢐ ꢕꢙ ꢚꢋ ꢛꢛ
ꢐ ꢕꢙ ꢚꢋ ꢛꢜ
www.ti.com
SBAS288D − JUNE 2003 − REVISED AUGUST 2004
PIN ASSIGNMENTS
SSOP PACKAGE
(TOP VIEW)
AVDD
AGND
VREFN
VREFP
AINCOM
AIN0
D3
D2
1
2
3
4
5
6
28
27
26
25
24
AVDD
AGND
1
2
3
4
20 D1
D1
D0/CLKOUT
19
18
17
D0/CLKOUT
SCLK
VREFN
SCLK
DIN
VREFP
AINCOM
AIN0
23 DIN
AIN1
16 DOUT
5
6
DOUT
7
8
9
22
21
20
ADS1255
ADS1256
15
AIN2
DRDY
CS
DRDY
AIN1
7
8
9
AIN3
14 CS
XTAL1/CLKIN
SYNC, PDWN
RESET
13
AIN4
AIN5
AIN6
10
19 XTAL1/CLKIN
XTAL2
18
12 XTAL2
11
12
DVDD 10
11
DGND
17 DGND
16 DVDD
AIN7 13
SYNC, PDWN
RESET
15
14
Terminal Functions
TERMINAL NO.
ANALOG/DIGITAL
INPUT/OUTPUT
NAME
AVDD
AGND
VREFN
VREFP
AINCOM
AIN0
ADS1255 ADS1256
DESCRIPTION
1
2
1
2
Analog
Analog power supply
Analog ground
Analog
3
3
Analog input
Analog input
Analog input
Analog input
Analog input
Analog input
Analog input
Analog input
Analog input
Analog input
Analog input
Negative reference input
Positive reference input
Analog input common
Analog input 0
4
4
5
5
6
6
AIN1
7
7
Analog input 1
AIN2
—
—
—
—
—
—
8
8
Analog input 2
AIN3
9
Analog input 3
AIN4
10
11
12
13
14
15
16
17
18
19
20
Analog input 4
AIN5
Analog input 5
AIN6
Analog input 6
AIN7
Analog input 7
(1)(2)
SYNC/PDWN
RESET
Digital input
Digital input
: active low Synchronization / power down input
: active low Reset input
Digital power supply
Digital ground
(1)(2)
9
DVDD
10
11
12
13
14
Digital
Digital
DGND
(3)
Digital
XTAL2
Crystal oscillator connection
Crystal oscillator connection / external clock input
(2)
XTAL1/CLKIN
CS
Digital/Digital input
(1)(2)
Digital input : active low Chip select
DRDY
DOUT
DIN
15
16
17
18
19
20
—
—
21
22
23
24
25
26
27
28
Digital output: active low
Digital output
Data ready output
Serial data output
Serial data input
Serial clock input
Digital I/O 0 / clock output
Digital I/O 1
(1)(2)
(1)(2)
(4)
Digital input
Digital input
Digital IO
Digital IO
Digital IO
Digital IO
SCLK
D0/CLKOUT
D1
(4)
(4)
D2
Digital I/O 2
(4)
D3
Digital I/O 3
(1)
(2)
(3)
(4)
Schmitt-Trigger digital input.
5V tolerant digital input.
Leave disconnected if external clock input is applied to XTAL1/CLKIN.
Schmitt-Trigger digital input when the digital I/O is configured as an input.
5
BB [ BURR-BROWN CORPORATION ]
