X9118 Datasheet, PDF (3/20 Pages) Intersil Corporation – Dual Suply/Low Power/1024-Tap/2-Wire Bus

X9118
PIN CONFIGURATION
V+
NC
A0
SCL
WP
SDA
V_SS
TSSOP
1
14
2
13
3
12
4 ^X9118 11
5
10
6
9
7
8
V_CC
R_L
R_H
R_W
NC
A1
V-
PIN ASSIGNMENTS
PIN
(TSSOP) SYMBOL
FUNCTION
1
V+ Analog Supply Voltage
2
NC No Connect
3
A0 Device Address for 2-wire bus
4
SCL Serial Clock for 2-wire bus
5
WP Hardware Write Protect
6
SDA Serial Data Input/Output for 2-wire
bus
7
V_SS System Ground
8
V- Analog Supply Voltage
9
A1 Device Address for 2-wire bus
10
NC No Connect
11
R_W Wiper terminal of the Potentiometer
12
R_H High terminal of the Potentiometer
13
R_L Low terminal of the Potentiometer
14
V_CC System Supply Voltage
PIN DESCRIPTIONS
Bus Interface Pins
SERIAL DATA INPUT/OUTPUT (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.
SERIAL CLOCK (SCL)
This input is used by 2-wire master to supply 2-wire
serial clock to the X9118.
DEVICE ADDRESS (A1–A0)
The address inputs are used to set the least significant
2 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 X9118. A maximum of 4 XDCP devices may
occupy the 2-wire serial bus.
HARDWARE WRITE PROTECT INPUT (WP)
The WP pin when LOW prevents nonvolatile writes to
the Data Registers.
Potentiometer Pins
R_H, R_L
The R_H and R_L pins are equivalent to the terminal
connections on a mechanical potentiometer.
R_W
The wiper pin is equivalent to the wiper terminal of a
mechanical potentiometer.
Bias Supply Pins
SYSTEM SUPPLY VOLTAGE (V_CC) AND SUPPLY
GROUND (V_SS)
The V_CC pin is the system or digital supply voltage.
The V_SS pin is the system ground.
ANALOG SUPPLY VOLTAGES (V+ AND V-)
These supplies are the analog voltage supplies for the
potentiometer. The V+ supply is tied to the wiper
switches while the V- supply is used to bias the
switches and the internal P+ substrate of the
integrated circuit. Both of these supplies set the
voltage limits of the potentiometer.
Other Pins
NO CONNECT
No connect pins should be left open. These pins are
used for Intersil manufacturing and testing purposes.
3
FN8161.1
March 25, 2005