ISL22316 Intersil Corporation, ISL22316 Datasheet - Page 9

• Manufacturer Part Number: ISL22316
• Manufacturer: Intersil Corporation

Typical Performance Curves
Pin Description
Potentiometers Pins
RH and RL
The high (RH) and low (RL) terminals of the ISL22316 are
equivalent to the fixed terminals of a mechanical
potentiometer. RH and RL are referenced to the relative
position of the wiper and not the voltage potential on the
terminals. With WR set to 127 decimal, the wiper will be
closest to RH, and with the WR set to 0, the wiper is closest
to RL.
RW
RW is the wiper terminal and is equivalent to the movable
terminal of a mechanical potentiometer. The position of the
wiper within the array is determined by the WR register.
SHDN
The SHDN pin forces the resistor to end-to-end open circuit
condition on RH and shorts RW to RL. When SHDN is
returned to logic high, the previous latch settings put RWi at
the same resistance setting prior to shutdown. This pin is
logically OR’d with SHDN bit in ACR register. I
still available in shutdown mode and all registers are
accessible. This pin must remain HIGH for normal operation.
Wiper Mid Point Movement
from 3Fh to 40h
FIGURE 15. DCP CONNECTION IN SHUTDOWN MODE
FIGURE 13. MIDSCALE GLITCH, CODE 3Fh TO 40h
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RH
RW
RL
(Continued)
2
C interface is
ISL22316
Bus Interface Pins
Serial Data Input/Output (SDA)
The SDA is a bidirectional serial data input/output pin for I
interface. It receives device address, operation code, wiper
address and data from an I
rising edge of the serial clock SCL, and it shifts out data after
each falling edge of the serial clock.
SDA requires an external pull-up resistor, since it is an open
drain input/output.
Serial Clock (SCL)
This input is the serial clock of the I
requires an external pull-up resistor, since it is an open drain
input.
Device Address (A1, A0)
The address inputs are used to set the least significant 2 bits
of the 7-bit I
address serial data stream must match with the Address
input pins in order to initiate communication with the
ISL22316. A maximum of four ISL22316 devices may
occupy the I
Principles of Operation
The ISL22316 is an integrated circuit incorporating one DCP
with its associated registers, non-volatile memory and an I
serial interface providing direct communication between a
host and the potentiometer and memory. The resistor array
is comprised of individual resistors connected in series. At
either end of the array and between each resistor is an
electronic switch that transfers the potential at that point to
the wiper.
The electronic switches on the device operate in a “make
before break” mode when the wiper changes tap positions.
FIGURE 14. LARGE SIGNAL SETTLING TIME
2
2
C interface slave address. A match in the slave
C serial bus.
2
C external master device at the
2
C serial interface. SCL
June 23, 2006
FN6186.0
2
2
C
C