X9258
PIN DESCRIPTIONS
Host Interface Pins
SERIAL CLOCK (SCL)
PIN CONFIGURATION
SOIC/TSSOP
A3
NC
A0
1
2
24
23
22
21
20
19
18
17
16
SCL
The SCL input is used to clock data into and out of the
X9258.
V
/R
W3 W3
V
V
V
/R
3
L2 L2
V
/R
H3 H3
/R
4
H2 H2
V
/R
/R
5
L3 L3
W2 W2
SERIAL DATA (SDA)
V–
V
V+
6
SDA is a bidirectional pin used to transfer data into
and out of the device. 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.
X9258
V
7
CC
SS
V
V
V
/R
V
/R
8
W1 W1
L0 L0
V
/R
/R
H0 H0
9
H1 H1
V
/R
/R
W0 W0
10
15
14
L1 L1
A1
A2
11
12
WP
13
SDA
DEVICE ADDRESS (A - A )
0
3
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 X9258. A maximum of 16
devices may occupy the 2-wire serial bus.
PIN NAMES
Symbol
Description
SCL
Serial Clock
Serial Data
SDA
A0-A3
Device Address
Potentiometer Pins
V
V
/R - V /R
H0 H0 H3 H3
/R - V /R
L0 L0 L3 L3
,
Potentiometer Pins
(terminal equivalent)
V /R (V /R - V /R ), V /R (V /R
H0 H0 H3 H3 L0 L0
L3 L3
-
H
H
L
L
V
/R
- V /R
Potentiometers Pins
(wiper equivalent)
V
/R )
W0 W0 W3 W3
The V /R and V /R inputs are equivalent to the
H
H
L
L
WP
Hardware Write Protection
Analog Supplies
terminal connections on either end of a mechanical
potentiometer.
V+,V-
V
V
System Supply Voltage
System Ground
CC
SS
V /R (V /R
W0 W0
- V /R )
W3 W3
W
W
The wiper outputs are equivalent to the wiper output of
a mechanical potentiometer.
NC
No Connection (Allowed)
PRINCIPLES OF OPERATION
The X9258 is highly integrated microcircuit
a
incorporating four resistor arrays and their associated
registers and counters and the serial interface logic
providing direct communication between the host and
the DCP potentiometers.
Hardware Write Protect Input (WP)
The WP pin when low prevents nonvolatile writes to
the Data Registers.
Analog Supplies V+, V-
Serial Interface—2-Wire
The Analog Supplies V+, V- are the supply voltages for
the DCP analog section.
The X9258 supports a bidirectional bus oriented
protocol. The protocol defines any device that sends
data onto the bus as a transmitter and the receiving
device as the receiver. The device controlling the
transfer is a master and the device being controlled is
the slave. The master will always initiate data transfers
FN8168.1
2
May 6, 2005
INTERSIL [ Intersil ]
