1 of 32

19-5047; 5/10

DS2480B

Serial to 1-Wire Line

Driver

www.maxim-ic.com

FEATURES

 Universal, Common-Ground Serial Port to 1-

Devices

 Communicates at Standard and Overdrive 1-

Wire speed and Serial Port Data Rates of

9600 (default), 19200, 57600, and 115200 bps

 Supports 12V EPROM Programming and

Stiff 5V Pullup for Sensors and EEPROM

 Self-Calibrating Time Base with

5%

Tolerance for Serial and 1-Wire

Communication

 Slew Rate Controlled 1-Wire Pulldown and

Active Pullup to Accommodate Long Lines

and Reduce Radiation

 User-Selectable RXD/TXD Polarity

Minimizes Component Count When

Interfacing to 5V Based RS232 Systems or

Directly to UARTs

 Programmable 1-Wire Timing and Driver

Characteristics Accommodate a Wide Range

of Slave Device Configurations at Standard

Speed

 Smart Protocol Combines Data and Control

Information Without Requiring Extra Pins

 Compatible with Optical, IR, and RF to

RS232 Converters

 Low-Cost 8-Pin SO Surface-Mount Package

 Operates Over 4.5V to 5.5V from -40°C to

+85°C

PIN ASSIGNMENT

PIN DESCRIPTION

GND

- Ground

1-W

- 1-Wire Input/Output

NC

- No Connection

- 4.5V to 5.5V

- Optional EPROM

Programming Voltage

POL

- RXD/TXD Polarity Select

TXD

- Serial Data from UART

RXD

- Serial Data to UART

ORDERING INFORMATION

PART

TEMP

RANGE

PIN-

PACKAGE

DS2480B+

-40°C to +85°C

8 SO

DS2480B+T&R -40°C to +85°C

8 SO

+ Denotes a lead(Pb)-free/RoHS-compliant package.

T&R = Tape and reel.

DESCRIPTION

The DS2480B is a serial port to 1-Wire interface chip that supports standard and overdrive speeds. It con-

nects directly to UARTs and 5V RS232 systems. Interfacing to RS232C (±12V levels) requires a passive

clamping circuit and one 5V to ±12V level translator. Internal timers relieve the host of the burden of

generating the time-critical 1-Wire communication waveforms. In contrast to the DS9097(E) where a full

character must be sent by the host for each 1-Wire time slot, the DS2480B can translate each character

into eight 1-Wire time slots, thereby increasing the data throughput significantly. In addition, the

DS2480B can be set to communicate at four different data rates, including 115.2kbps, 57.6kbps, and

19.2kbps, with 9.6kbps being the power-on default. Command codes received from the host’s crystal

controlled UART serve as a reference to continuously calibrate the on-chip timing generator. The

1

2

3

4

8

7

6

5

GND

1-W

NC

VDD

RXD

TXD

POL

VPP

8-Pin SO (150 mil)