DATASHEET
X9259
Single Supply/Low Power/256-Tap/2-Wire Bus Quad Digitally-Controlled
(XDCP™) Potentiometers
The X9259 integrates four digitally controlled potentiometers
(XDCP) on a monolithic CMOS integrated circuit.
The digitally controlled potentiometers are implemented with
a combination of resistor elements and CMOS switches. The
position of the wipers are controlled by the user through the
2-wire bus interface. Each potentiometer has associated with
it a volatile Wiper Counter Register (WCR) and four nonvolatile
Data Registers that can be directly written to and read by the
user. The content of the WCR controls the position of the wiper.
At power-up, the device recalls the content of the default Data
Registers of each DCP (DR00, DR10, DR20, and DR30) to the
corresponding WCR.
The XDCP can be used as a three-terminal potentiometer or as
a two-terminal variable resistor in a wide variety of
applications including control, parameter adjustments, and
signal processing.
FN8169
Rev 6.00
December 12, 2014
Features
• Four separate potentiometers in one package
• 256 resistor taps–0.4% resolution
• 2-wire serial interface for write, read, and
transfer operations of the potentiometer
• Wiper resistance: 100Ω typical at V
CC
= 5V
• 4 nonvolatile data registers for each potentiometer
• Nonvolatile storage of multiple wiper positions
• Standby current <5µA max
• V
CC
: 2.7V to 5.5V operation
• 50kΩ version of total resistance
• Endurance: 100,000 data changes per bit per register
• 100 year data retention
• Single supply version of X9258
• 24 Ld SOIC, 24 Ld TSSOP
• Low power CMOS
• Pb-Free (RoHS compliant)
Functional Diagram
V
CC
R
H0
R
H1
R
H2
R
H3
A3
A2
A1
A0
SDA
SCL
2-WIRE
INTERFACE
POWER UP,
INTERFACE
CONTROL
AND
STATUS
WCR0
DR00
DR01
DR02
DR03
DCP0
WCR1
DR10
DR11
DR12
DR13
DCP1
WCR2
DR20
DR21
DR22
DR23
DCP2
WCR3
DR30
DR31
DR32
DR33
DCP3
V
SS
WP
R
W0
R
L0
R
W1
R
L1
R
W2
R
L2
R
W3
R
L3
FN8169 Rev 6.00
December 12, 2014
Page 1 of 21
X9259
Ordering Information
PART NUMBER
(Notes
1, 3)
X9259US24Z (Note
2)
X9259UV24Z
X9259US24IZ (Note
2)
X9259UV24IZ (Note
2)
X9259US24Z-2.7 (Note
2)
X9259US24IZ-2.7 (Note
2)
X9259UV24Z-2.7
X9259UV24IZ-2.7 (Note
2)
NOTES:
1. Intersil Pb-free plus anneal products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate
termination finish, which are RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are MSL
classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
2. Add "T1" suffix for tape and reel.
3. For Moisture Sensitivity Level (MSL), please see product information page for
X9259.
For more information on MSL, please see tech brief
TB363.
PART
MARKING
X9259US Z
X9259UV Z
X9259US ZI
X9259UV ZI
X9259US ZF
X9259US ZG
X9259UV ZF
X9259UV ZG
2.7 to 5.5
V
CC
LIMITS
(V)
5 ±10%
R
TOTAL
(kΩ)
50
TEMP RANGE
(°C)
0 to +70
0 to +70
-40 to +85
-40 to +85
0 to +70
-40 to +85
0 to +70
-40 to +85
PACKAGE
(RoHS Compliant)
24 Ld SOIC
24 Ld TSSOP
24 Ld SOIC
24 Ld TSSOP
24 Ld SOIC
24 Ld SOIC
24 Ld TSSOP
24 Ld TSSOP
PKG.
DWG. #
M24.3
M24.173
M24.3
M24.173
M24.3
M24.3
M24.173
M24.173
Circuit Level Applications
• Vary the gain of a voltage amplifier
• Provide programmable DC reference voltages for comparators
and detectors
• Control the volume in audio circuits
• Trim out the offset voltage error in a voltage amplifier circuit
• Set the output voltage of a voltage regulator
• Trim the resistance in Wheatstone bridge circuits
• Control the gain, characteristic frequency and
Q-factor in filter circuits
• Set the scale factor and zero point in sensor signal
conditioning circuits
• Vary the frequency and duty cycle of timer ICs
• Vary the DC biasing of a pin diode attenuator in RF circuits
• Provide a control variable (I, V, or R) in feedback
circuits
System Level Applications
• Adjust the contrast in LCD displays
• Control the power level of LED transmitters in
communication systems
• Set and regulate the DC biasing point in an RF power amplifier
in wireless systems
• Control the gain in audio and home entertainment systems
• Provide the variable DC bias for tuners in RF wireless systems
• Set the operating points in temperature control
systems
• Control the operating point for sensors in industrial systems
• Trim offset and gain errors in artificial intelligent
systems
FN8169 Rev 6.00
December 12, 2014
Page 2 of 21
X9259
Pin Configuration
X9259
24 LD SOIC/TSSOP
TOP VIEW
DNC
A0
R
W3
R
H3
R
L3
NC
V
CC
R
L0
R
H0
R
W0
A2
WP
1
2
3
4
5
6
7
8
9
10
11
12
X9259
24
23
22
21
20
19
18
17
16
15
14
13
A3
SCL
R
L2
R
H2
R
W2
NC
V
SS
R
W1
R
H1
R
L1
A1
SDA
Pin Descriptions
PIN
#
2
3
4
5
7
8
9
10
11
12
13
14
15
16
17
18
20
21
22
23
24
6, 19
1
PIN
NAME
A0
R
W3
R
H3
R
L3
V
CC
R
L0
R
H0
R
W0
A2
WP
SDA
A1
R
L1
R
H1
R
W1
V
SS
R
W2
R
H2
R
L2
SCL
A3
NC
DNC
DESCRIPTION
Device Address for 2-wire bus. (See
Note 4)
Wiper Terminal of DCP3
High Terminal of DCP3
Low Terminal of DCP3
System Supply Voltage
Low Terminal of DCP0
High Terminal of DCP0
Wiper Terminal of DCP0
Device Address for 2-wire bus. (See
Note 4)
Hardware Write Protect – Active Low
Serial Data Input/Output for 2-wire bus.
Device Address for 2-wire bus. (See
Note 4)
Low Terminal of DCP1
High Terminal of DCP1
Wiper Terminal of DCP1
System Ground
Wiper Terminal of DCP2
High Terminal of DCP2
Low Terminal of DCP2
Serial Clock for 2-wire bus.
Device Address for 2-wire bus. (See
Note 4)
No Connect
Do Not Connect
NOTE:
4. A0 through A3 Device address pins must be tied to a logic level.
FN8169 Rev 6.00
December 12, 2014
Page 3 of 21
X9259
Functional 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 a 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.
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 4 potentiometers,
there are 4 sets of R
H
and R
L
such that R
H0
and R
L0
are the
terminals of DCP0 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 4 sets of R
W
such that R
W0
is the terminal of DCP0 and
so on.
Bias Supply Pins
SYSTEM SUPPLY VOLTAGE (V
CC
) AND SUPPLY
GROUND (V
SS
)
The V
CC
pin is the system supply voltage. The V
SS
pin is the
system ground.
SERIAL CLOCK (SCL)
This input is used by a 2-wire master to supply a 2-wire serial
clock to the X9259.
DEVICE ADDRESS (A3 THROUGH 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 X9259. A maximum of 16 devices may
occupy the 2-wire serial bus. Device pins A3 through A0 must be
tied to a logic level, which specifies the external address of the
device, see
Figures 3, 4,
and
5.
Other Pins
NO CONNECT
No connect pins should be left open. These pins are used for
Intersil manufacturing and testing purposes.
HARDWARE WRITE PROTECT INPUT (WP)
The WP pin when LOW, prevents nonvolatile writes to the Data
Registers.
One of Four Potentiometers
#: 0, 1, 2, or 3
SERIAL DATA PATH
FROM INTERFACE
CIRCUITRY
DR#0
8
DR#1
8
PARALLEL
BUS
INPUT
WIPER
COUNTER
REGISTER
(WCR#)
SERIAL
BUS
INPUT
R
H
DR#2
DR#3
COUNTER
---
DECODE
DCP
CORE
R
W
IF WCR = 00[H] then R
W
is closest to R
L
IF WCR = FF[H] then R
W
is closest to R
H
INC/DEC
LOGIC
UP/DN
MODIFIED SCK
UP/DN
CLK
R
L
FIGURE 1. DETAILED POTENTIOMETER BLOCK DIAGRAM
FN8169 Rev 6.00
December 12, 2014
Page 4 of 21
X9259
Principles of Operation
The X9259 is an integrated circuit incorporating four DCPs and
their associated registers and counters, and the serial interface
providing direct communication between a host and the
potentiometers.
transferring the contents of one of four associated data registers
via the XFR Data Register instruction (parallel load); it can be
modified one step at a time by the Increment/Decrement
instruction (see
“Instructions”
section on
page 8
for more
details). Finally, it is loaded with the contents of its data register
zero (DR#0) upon power-up, (see
Figure 1 on page 4).
The Wiper Counter Register is a volatile register; that is, its
contents are lost when the X9259 is powered-down. Although the
register is automatically loaded with the value in DR#0 upon
power-up, this may be different from the value present at
power-down. Power-up guidelines are recommended to ensure
proper loadings of the DR#0 value into the WCR# (see
AN162).
DCP Description
Each DCP is implemented with a combination of resistor
elements and CMOS switches. The physical ends of each DCP are
equivalent to the fixed terminals of a mechanical potentiometer
(R
H
and R
L
pins). The RW pin is an intermediate node, equivalent
to the wiper terminal of a mechanical potentiometer.
The position of the wiper terminal within the DCP is controlled by
an 8-bit volatile Wiper Counter Register (WCR).
Data Registers (DR)
Each of the four DCPs has four 8-bit nonvolatile Data Registers.
These can be read or written directly by the host. Data can also
be transferred between any of the four data registers and the
associated Wiper Counter Register. All operations changing data
in one of the data registers is a nonvolatile operation and takes a
maximum of 10ms.
If the application does not require storage of multiple settings for
the potentiometer, the Data Registers can be used as regular
memory locations for system parameters or user preference
data.
Bit [7:0] are used to store one of the 256 wiper positions
(0 ~ 255).
Power Up and Down Recommendations
There are no restrictions on the power-up or power-down
conditions of V
CC
and the voltages applied to the potentiometer
pins provided that V
CC
is always more positive than or equal to
V
H
, V
L
, and V
W
, i.e., V
CC
V
H
, V
L
, V
W
. The V
CC
ramp rate
specification is always in effect.
Wiper Counter Register (WCR)
The X9259 contains four Wiper Counter Registers, one for each
potentiometer. The Wiper Counter Register can be envisioned as
a 8-bit parallel and serial load counter with its outputs decoded
to select one of 256 wiper positions along its resistor array. The
contents of the WCR can be altered in four ways: it may be
written directly by the host via the Write Wiper Counter Register
instruction (serial load); it may be written indirectly by
TABLE 1. WIPER COUNTER REGISTER, WCR (8-BIT), WCR[7:0]: USED TO STORE THE CURRENT WIPER POSITION (VOLATILE).
WCR7
(MSB)
WCR6
WCR5
WCR4
WCR3
WCR2
WCR1
WCR0
(LSB)
TABLE 2. DATA REGISTER, DR (8-BIT), BIT [7:0]: USED TO STORE WIPER POSITIONS OR DATA (NONVOLATILE).
BIT 7
(MSB)
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
(LSB)
FN8169 Rev 6.00
December 12, 2014
Page 5 of 21