Rainbow Electronics DS3903 - Manual

General Description
The DS3903 contains three nonvolatile (NV) low tem-
perature coefficient digital potentiometers, which can
be accessed through a 2-wire bus. It operates in both
3V and 5V systems, and it features a write-protect pin
that can lock the positions of the potentiometers. An
address pin allows two DS3903s to be placed on the
same 2-wire bus.
Applications
Power-Supply Calibration
Mobile Phones and PDAs
Fiber Optics Transceiver Modules
Portable Electronics
A Small, Low-Cost Replacement for Mechanical
Potentiometers
Features
♦ Three 128-Position Linear Potentiometers
(Two 10k Ω, One 90kΩ)
♦ NV Wiper Storage
♦ 0 to 5.5V on Any Potentiometer Terminal
Independent of V CC
♦ Low End-to-End Temperature Coefficient
♦ Operates on an Industry-Standard 2-Wire Bus
♦ Write-Protect Pin
♦ Supply Voltage: 3V or 5V
♦ Operating Temperature Range: -40°C to +85°C
♦ Packaging: 20-Pin TSSOP
DS3903
Triple 128-Position Nonvolatile
Digital Potentiometer
_____________________________________________ Maxim Integrated Products 1
20
18
17
16
15
14
13
11
1
3
4
5
6
7
8
10
12 9
SDA V CC
19 2 SCL N.C.
N.C.
N.C.
N.C.
H0
W0
H1
H2
W2
TSSOP
A0
WP
W1
N.C.
L0
L1
L2
GND
DS3903
Pin Configuration
0.1 µF
4.7k Ω
2-WIRE
MASTER
V CC
V CC
V CC
VREF1
VREF2
5.1k Ω
Iref
V CC
SCL
SDA
POTENTIOMETER 2
10k
Ω
ADDDR FAh
POTENTIOMETER 0
10k
Ω
ADDDR F9h
POTENTIOMETER 1
90k
Ω
ADDDR F8h
WP
A0
GND
4.7k Ω
VARIABLE RESISTANCE
FOR ADJUSTABLE
CURRENT SOURCE
HIGH-OUTPUT-IMPEDANCE
VOLTAGE REFERENCE
BUFFERED
VOLTAGE
REFERENCE
V CC
MAX427
DS3903
Typical Operating Circuit
Ordering Information
Rev 0; 6/02
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
PART TEMP RANGE PIN-PACKAGE
DS3903E-020 -40°C to +85°C 20 TSSOP
DS3903E-020/T&R -40°C to +85°C
20 TSSOP
(Tape-and-Reel)