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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 USB DS9490B iButton
PC USB DS9490R
DS1402D-DR8
ORDERING INFORMATION
PART DESCRIPTION
DS9490B# USB Single F5 iButton Holder
with Protective Cap
DS9490R# USB to 1-Wire RJ11
#Denotes a RoHS-compliant device that may include
lead(Pb) that is exempt under the RoHS requirements.
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
1-Wire 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® operating
systems can be found on the iButton website under software support at
www.maxim-ic.com/products/ibutton/software/tmex/index.cfm.
DS9490R/DS9490B
USB to 1-Wire/iButton Adapte
r
www.maxim-ic.com
1-Wire, iButton, and Thermochron are registered trademarks of Maxim
Integrated Products, Inc.
Blue Dot is a trademark of Maxim Integrated Products, Inc.
Windows and Windows XP are registered trademarks of Microsoft Corp.
19-4881; Rev 8/09
DS9490
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Figure 1. DS9490R
Figure 2. DS9490B
*
*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
12-BIT
FIXED
(000H)
36-BIT SERIAL
NUMBER 8-BIT FAMILY
CODE (81H)
MSB LSB MSB LSB MSB LSB MSB LSB
DS9490
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PIN CONFIGURATION
Figure 4. 1-Wire RJ11 SOCKET FOR DS9490R
PIN SIGNAL
NAME DESCRIPTION
1 VDD 5VDC Output
2 GND Power Ground
3 OW 1-Wire Data
4 GND_OW 1-Wire Return
5 SUSO USB Suspend Output
6 N.C. No Connection
Figure 5. iButton SOCKET FOR DS9490B
PIN SIGNAL
NAME DESCRIPTION
1 OW 1-Wire Data
2 GND_OW 1-Wire Return
1
2
*
*Note: The data contact faces down and away from the embossed ‘i’. Once the iButton is inserted in the
enclosure, snap the end cap over it. The end cap is removed by depressing the release tab with a
paper clip, swinging it fully open, and sliding out the hinge.
Looking into Fem ale R J11
Connector
654321
DS9490
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MECHANICAL DIMENSIONS
All dimensions are in millimeters.
Figure 6. DS9490R
11.66
3.12
20.42
42.65
13.89
21.54
Figure 7. DS9490B
3.28
11.66
56.82
24.94
16.54 8.74
ENVIRONMENTAL REQUIREMENTS
CONDITION PARAMETER VALUE
Storage Temperature -10°C to +85°C
Storage Relative humidity, noncondensing 95%
Storage Duration 1yr (max) at 95%RH and +85C
Operating Temperature 0°C to +70°C
Operating Relative humidity, noncondensing 80%
DS9490
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ELECTRICAL CHARACTERISTICS
PARAMETER SPECIFICATION
USB I/F As defined in Chapter 7 of the USB Specification*
1-Wire I/F See the DS2490 data sheet**
The DS9490R and DS9490B consume 58mA in USB active mode and 0.5mA in suspend mode*. The
DS9490R has the VBUS power and ground available on the RJ11 connector. In active mode the current
available to an externally powered fixture is 42mA* (100mA to 58mA); however it is recommended that
no more than 25mA be used. An external circuit can detect when the module is in suspend by monitoring
the SUSO signal on Pin 5 of the RJ11 connector. When this condition is detected, the external circuit
must also go into a low power state. NOTE: The SUSO pin of the DS2490 is an open drain output and
requires a pullup resistor to create a valid signal. See the DS2490 data sheet for the conditions where
SUSO is active. Revision C of the DS9490R and all revisions of the DS9490R# have SUSO routed to the
RJ11 connector. The availability of SUSO at the RJ11 connector is not production tested. Therefore,
before relying on SUSO in an application, first verify the presence of this signal with the particular
adapter.
*Guaranteed by design, not production tested.
**Tested at DS2490 component level.
Figure 8. FUNCTIONAL DIAGRAM
EMI Filter
VBUS
D-
D+
GND VIN VOUT
EN
N/C GND
LP2980IM5-3.3
PMOD VD
NC NC
NC NC
NC NC
VB X1
SUSO X0
D- NC
D+ VPP
NC NC
OW NC
NC NC
GND NC
DS2490
C2
1.0uF
EMI Filter
C3
4.7
R2 24
R3 24
R1
1.5K
C1
0.1uF
OW
GND
DS2401
OW
GND
DS9503
USB
Connector
C6
33pF C5
33pF
X1
12Mhz
L1
L2
C7
33pF C8
33pF
U1
U2
U3
U4
J2
1
2
1
2
J1
1
2
3
4 1
3
4
5
2
1
5
7
8
12
24
19
20
17
10
1
2
3
4
5
6
Female RJ11
DS9490R
DS9490B
1
2
iButton Socket
J3
6
5
3
1
R7 10
DS9490
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Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim
reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.
REVISION HISTORY
REVISION
DATE DESCRIPTION PAGES
CHANGED
8/09 Removed references to leaded packages in the Ordering Information
table. 1
