DS9490R/DS9490B
USB to 1-Wire/iButton Adapter
www.maxim-ic.com
FEATURES
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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
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
APPLICATIONS
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ORDERING INFORMATION
PART
DS9490B
DS9490R
DESCRIPTION
USB Single F5 iButton Holder
with Protective Cap
USB to 1-Wire RJ11
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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 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 registered trademark of Micosoft Corp.
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050503
DS9490
Figure 1. DS9490R
* Color subject to change
Figure 2. DS9490B
* Color subject to change
*
*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
8-BIT
CRC CODE
MSB
LSB
12-BIT
FIXED
(000H)
MSB
36-BIT SERIAL
NUMBER
LSB MSB
LSB
8-BIT FAMILY
CODE (81H)
LSB MSB
LSB
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DS9490
PIN CONFIGURATION
Figure 4. 1-WIRE RJ11 SOCKET FOR DS9490R
PIN
1
2
3
4
5, 6
6
SIGNAL
NAME
V
DD
GND
OW
GND_OW
N.C.
N.C.
DESCRIPTION
5VDC Output
Power Ground
1-Wire Data
1-Wire Return
No Connection
No Connection
6
5
4
3
2
1
Looking into Female RJ11
Figure 5. iBUTTON SOCKET FOR DS9490B
PIN
1
2
SIGNAL
NAME
OW
GND_OW
DESCRIPTION
1-Wire Data
1-Wire Return
2
*
1
*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,
swinging it fully open, and sliding out the hinge.
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DS9490
MECHANICAL DIMENSIONS
All dimensions are in millimeters.
Figure 6. DS9490R
11.66
20.42
42.65
13.89
21.54
3.12
Figure 7. DS9490B
56.82
24.94
11.66
8.74
16.54
3.28
ENVIRONMENTAL REQUIREMENTS
CONDITION
Storage
Storage
Storage
Operating
Operating
PARAMETER
Temperature
Relative humidity, noncondensing
Duration
Temperature
Relative humidity, noncondensing
VALUE
-10°C to +85°C
95%
1yr (max) at 95%RH and +85°C
0°C to +70°C
80%
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DS9490
ELECTRICAL CHARACTERISTICS
PARAMETER
USB I/F
1-Wire I/F
SPECIFICATION
As defined in Chapter 7 of the USB Specification*
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 V
BUS
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. Note that in suspend mode there is zero current available to an external
circuit. An external circuit cannot detect when the module is in suspend or active mode. Consequently,
when in suspend mode, the DS9490R module with external circuit combination is in violation of the USB
power specification. Application developers should be aware of this when using this module in
conjunction with an externally powered circuit on power restricted platforms such as laptops.
*Guaranteed by design, not production tested.
**Tested at DS2490 component level.
Figure 8. FUNCTIONAL DIAGRAM
USB
Connector
VBUS
D-
D+
GND
J1
1
2
3
4
EMI Filter
L2
C2
1.0uF
1
3
4
EMI Filter
L1
C1
0.1uF
5
C3
4.7
2
R1
1.5K
5
R2 24
7
8
10
C7
33pF
C8
33pF
12
1
LP2980IM5-3.3
VIN
EN
N/C
U1
VOUT
GND
DS2490
PMOD
NC
NC
NC
VB
SUSO
D-
D+
NC
OW
NC
GND
U2
24
R3 24
VD
NC
NC
NC
X1
X0
NC
VPP
NC
NC
NC
NC
19
20
17
3
C6
33pF
1
X1
12Mhz
C5
33pF
DS2401
OW
GND
U3
2
1
6
5
DS9503
OW
GND
U4
1
Female RJ11
2
1
2
3
4
5
6
J2
DS9490R
iButton Socket
1
2
J3
DS9490B
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PCB设计
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