MAX5422 Datasheet, PDF (1/11 Pages) Maxim Integrated Products – 256-Tap, Nonvolatile, SPI-Interface, Digital Potentiometers

19-3371; Rev 0; 7/04
256-Tap, Nonvolatile, SPI-Interface,
Digital Potentiometers
General Description
The MAX5422/MAX5423/MAX5424 nonvolatile, linear-
taper, digital potentiometers perform the function of a
mechanical potentiometer, but replace the mechanics
with a simple 3-wire SPI™-compatible digital interface.
Each device performs the same function as a discrete
potentiometer or variable resistor and has 256 tap points.
The devices feature an internal, nonvolatile EEPROM
used to store the wiper position for initialization during
power-up. The 3-wire SPI-compatible serial interface
allows communication at data rates up to 5MHz, mini-
mizing board space and reducing interconnection com-
plexity in many applications.
The MAX5422/MAX5423/MAX5424 provide three nomi-
nal resistance values: 50kΩ (MAX5422), 100kΩ
(MAX5423), or 200kΩ (MAX5424). The nominal resistor
temperature coefficient is 35ppm/°C end-to-end and
only 5ppm/°C ratiometric. This makes the devices ideal
for applications requiring a low-temperature-coefficient
variable resistor, such as low-drift, programmable gain-
amplifier circuit configurations.
The MAX5422/MAX5423/MAX5424 are available in a
3mm x 3mm 8-pin TDFN package, and are specified
over the extended -40°C to +85°C temperature range.
Applications
Mechanical Potentiometer Replacement
Low-Drift Programmable Gain Amplifiers
Audio Volume Control
Liquid-Crystal Display (LCD) Contrast Control
Low-Drift Programmable Filters
Functional Diagram
H
8-BIT ₈
V_DD
SHIFT
REGISTER
8-BIT ⁸
LATCH
256- 256
POSITION
DECODER
W
GND
L
CS
POR
SCLK
SPI
INTERFACE
8-BIT
MAX5422
NV
MAX5423
DIN
MEMORY
MAX5424
Features
o Wiper Position Stored in Nonvolatile Memory
(EEPROM) and Recalled Upon Power-Up or
Interface Command
o 3mm x 3mm x 0.8mm TDFN Package
o 35ppm/°C End-to-End Resistance Temperature
Coefficient
o 5ppm/°C Ratiometric Temperature Coefficient
o 50kΩ, 100kΩ, and 200kΩ Resistor Values
o 5MHz SPI-Compatible Serial Interface
o 500nA (typ) Static Supply Current
o Single-Supply Operation: +2.7V to +5.25V
o 256 Tap Positions
o ±0.5 LSB DNL in Voltage-Divider Mode
o ±0.5 LSB INL in Voltage-Divider Mode
SPI is a trademark of Motorola, Inc.
TOP VIEW
Pin Configuration
V_DD 1
SCLK 2
DIN 3
CS 4
MAX5422
MAX5423
MAX5424
8H
7W
6L
5 GND
TDFN (3mm x 3mm)
Ordering Information/Selector Guide
PART
MAX5422ETA
MAX5423ETA
MAX5424ETA
*EP = Exposed pad.
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
END-TO-END
RESISTANCE (kΩ)
50
100
200
PIN-PACKAGE
8 TDFN-EP*
8 TDFN-EP*
8 TDFN-EP*
TOP MARK
AIJ
AII
AIH
________________________________________________________________ Maxim Integrated Products 1
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