X9269
PIN DESCRIPTIONS
Bus Interface Pins
S
ERIAL
D
ATA
I
NPUT
/O
UTPUT
(SDA)
The SDA is a bidirectional serial data input/output pin
for a 2-Wire slave device and is used to transfer data
into and out of the device. It receives device address,
opcode, wiper register address and data sent from an
2-Wire master at the rising edge of the serial clock
SCL, and it shifts out data after each falling edge of the
serial clock SCL.
It is an open drain output and may be wire-ORed with
any number of open drain or open collector outputs. An
open drain output requires the use of a pull-up resistor.
For selecting typical values, refer to the guidelines for
calculating typical values on the bus pull-up resistors
graph.
S
ERIAL
C
LOCK
(SCL)
This input is used by 2-Wire master to supply 2-Wire
serial clock to the X9269.
D
EVICE
A
DDRESS
(A3–A0)
The address inputs are used to set the least significant
4 bits of the 8-bit slave address. A match in the slave
address serial data stream must be made with the
Address input in order to initiate communication with
the X9269. A maximum of 16 devices may occupy the
2-Wire serial bus.
Potentiometer Pins
R
H
, R
L
The R
H
and R
L
pins are equivalent to the terminal
connections on a mechanical potentiometer. Since
there are 2 potentiometers, there are 2 sets of R
H
and
R
L
such that R
H0
and R
L0
are the terminals of POT 0
and so on.
R
W
The wiper pin are equivalent to the wiper terminal of a
mechanical potentiometer. Since there are 4
potentiometers, there are 2 sets of R
W
such that R
W0
is the terminal of POT 0 and so on.
Bias Supply Pins
S
YSTEM
S
UPPLY
V
OLTAGE
(V
CC
)
AND
S
UPPLY
G
ROUND
(V
SS
)
The V
CC
pin is the system supply voltage. The V
SS
pin
is the system ground.
Other Pins
N
O
C
ONNECT
No connect pins should be left open. This pins are used for
Xicor manufacturing and testing purposes.
H
ARDWARE
W
RITE
P
ROTECT
I
NPUT
(WP)
The WP pin when LOW prevents nonvolatile writes to
the Data Registers.
REV 1.1.11 2/17/03
www.xicor.com
Characteristics subject to change without notice.
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