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DS9490R/DS9490B
USB to 1-Wire/iButton Adapter
FEATURES
§ High-Speed 12Mbps Universal Serial Bus
(USB) Interface
§ Supports Standard and Overdrive 1-Wire
®
Communication
§ Slew-Rate-Controlled 1-Wire Timing and
Active Pullup for Improved 1-Wire Network
Performance
§ DS9490R has an RJ11 Interface for Standard
Connectivity Accessories such as the
DS1402D-DR8
§ DS9490B has an iButton® Interface and
Retains a Fixed iButton
§ Built-In Custom DS2401 Identification Chip
§ Reads all 1-Wire and iButton Devices. Writes
All Except EPROM 1-Wire/iButton Devices
APPLICATIONS
§ Software Authorization—Protection against
software piracy by tying software operation to
the presence of iButton hardware.
§ iButton Initialization and Download—
Loggers like the Thermochron® can be
missioned and downloaded. Monetary
iButtons can be refilled with money.
§ Demonstration—Demonstrate the features of
iButtons or 1-Wire chips on personal
computers.
§ Development—Aid development of 1-Wire
applications by providing a PC interface to
verify device contents and state.
TYPICAL OPERATING CIRCUIT
PC
PC
USB
USB
DS9490B
DS9490R
DS1402D-DR8
iButton
ORDERING INFORMATION
PART DESCRIPTION
DS9490B USB Single F5 iButton Holder
with Protective Cap
DS9490R USB to 1-Wire RJ11
PACKAGING/SHIPPING
INFORMATION
The part is shipped individually in an anti-static
bag.
DESCRIPTION
The DS9490B is a USB bridge and holder for a single F5-size iButton. The iButton is securely held
behind a latched door. The DS9490R is a USB bridge with 1-Wire RJ11 interface to accommodate 1Wire receptacles and networks. The DS1402D-DR8 (Blue Dot™) can readily be used in conjunction with
the DS9490R to create an iButton PC reader. Both adapters are based on the DS2490 USB to 1-Wire
bridge chip.
PC software drivers for Windows® 98, Windows 2000, Windows ME, and Windows XP can be found on
the iButton website under software support at: http://www.ibutton.com/software/tmex/index.html
1-Wire, iButton, and Thermochron are registered trademarks of
Dallas Semiconductor.
Blue Dot is a trademark of Dallas Semiconductor.
Windows is a re
istered trademark of Micosoft Corp.
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Figure 1. DS9490R
* Color subject to change
Figure 2. DS9490B
* Color subject to change
DS9490
*
*Note: To eject an iButton, insert a straightened paper clip into the side access hole of the DS9490B.
Push the paper clip in the direction of the iButton. A different iButton can then be inserted. The
data contact faces down and away from the embossed ‘i’. Before inserting the paper clip
disconnect the DS9490B from the USB bus.
Each USB bridge contains a unique built-in identification chip. The identification chip is a custom
DS2401 that is a 64-bit ID number (see Figure 3).
Figure 3. DS2401 ID CHIP 64-BIT LASERED ROM
MSB LSB
8-BIT
CRC CODE
MSB LSB MSB LSB MSB LSB MSB LSB
12-BIT
FIXED
(000H)
36-BIT SERIAL
NUMBER
8-BIT FAMILY
CODE (81H)
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