CAT5261
Dual Digitally Programmable Potentiometers
(DPP™) with 256 Taps and SPI Interface
FEATURES
DESCRIPTION
Two linear-taper digitally programmable
The CAT5261 is two Digitally Programmable
Potentiometers (DPPs™) integrated with control logic
and 8 bytes of NVRAM memory. Each DPP consists of
a series of resistive elements connected between two
externally accessible end points. The tap points
between each resistive element are connected to the
wiper outputs with CMOS switches. A separate 8-bit
control register (WCR) independently controls the wiper
tap switches for each DPP. Associated with each wiper
control register are four 8-bit non-volatile memory data
registers (DR) used for storing up to four wiper settings.
Writing to the wiper control register or any of the non-
volatile data registers is via a SPI serial bus. On power-
up, the contents of the first data register (DR0) for each
of the potentiometers is automatically loaded into its
respective wiper control register.
potentiometers
256 resistor taps per potentiometer
End to end resistance 50kΩ or 100kΩ
Potentiometer control and memory access via
SPI interface
Low wiper resistance, typically 100
Nonvolatile memory storage for up to four
wiper settings for each potentiometer
Automatic recall of saved wiper settings at
power up
2.5 to 6.0 volt operation
Standby current less than 1µA
1,000,000 nonvolatile WRITE cycles
100 year nonvolatile memory data retention
24-lead SOIC and 24-lead TSSOP
Industrial temperature range
The CAT5261 can be used as a potentiometer or as a
two terminal, variable resistor. It is intended for circuit
level or system level adjustments in a wide variety of
applications. It is available in the -40°C to 85°C
industrial operating temperature range and offered in
a 24-lead SOIC and TSSOP package.
Industrial temperature range
For Ordering Information details, see page 14.
FUNCTIONAL DIAGRAM
PIN CONFIGURATION
SOIC/TSSOP (W, Y)
¯¯¯¯¯
R
H0
R
H1
CS
SCK
SI
SO
A0
1
2
3
4
5
6
7
8
24
HOLD
WIPER
CONTROL
REGISTERS
SPI BUS
INTERFACE
23 SCK
22 NC
21 NC
20 NC
19 NC
18 GND
17 RW1
R
R
W0
SO
NC
NC
NC
NC
VCC
RL0
W1
CAT
5261
WP
A0
A1
NONVOLATILE
DATA
REGISTERS
CONTROL
LOGIC
HOLD
R
L0
R
L1
RH0
9
16 RH1
RW0 10
15 RL1
14 A1
13 SI
¯¯¯
CS
11
12
¯¯¯
WP
© Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
1
Doc. No. MD-2122 Rev. E