DS2490Y Maxim Integrated Products, DS2490Y Datasheet - Page 3

• Manufacturer Part Number: DS2490Y
• Description: IC BRIDGE CLIP USB TO 1-W 24SOIC
• Manufacturer: Maxim Integrated Products

Specifications of DS2490Y

• Applications: USB
• Interface: 1-Wire
• Voltage - Supply: 3 V ~ 5.5 V
• Package / Case: 24-SOIC (7.5mm Width)
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

OVERVIEW
The DS2490 directly interfaces a USB port to a 1-Wire bus. As shown in Figure 1, the DS2490
incorporates a USB physical interface, a USB device controller coupled with a 1-Wire-specific USB
function core, and a 1-Wire bus interface controller. The 1-Wire interface controller shapes the slopes of
the 1-Wire waveforms, applies strong pullup to 5V, and reads the 1-Wire bus using a non-TTL threshold
to maximize the noise margin for best performance on large 1-Wire Networks. 1-Wire waveform timing
is accurately controlled with a crystal-based oscillator.
The DS2490 also supports USB remote wake-up which enables the DS2490-based USB peripheral to
send resume signaling to a suspended host system. If the remote wake-up function is enabled and the host
system is in a suspended state, a 1-Wire device attachment will cause the DS2490 to perform a host
system wake-up and allow the 1-Wire device to be serviced.
DS2490 FUNCTIONAL BLOCK DIAGRAM Figure 1
Typical application examples of the DS2490 are shown in Figure 2 (a to c). As shown in all the examples,
all host control and communication with the device is accomplished over a USB communication link. A
USB vendor-specific command set, as defined in this document, is used to select operational modes
(MODE COMMANDS), control command processing (CONTROL COMMANDS), and communicate
over the 1-Wire interface (COMMUNICATION COMMANDS). Shown in Figure 2, example (a) is a
DS2490-based USB peripheral application. The peripheral function is a USB to 1-Wire adapter and
provides both USB and 1-Wire I/O connections. In this example, the peripheral is attached to the USB
enabled host computer either directly at a root port or through a USB hub. The 1-Wire bus interface
provided by the DS2490 supports all 1-Wire devices manufactured by Dallas Semiconductor as well as
SECTION
ELECTRICAL CHARACTERISTICS
APPLICATION INFORMATION
APPENDIX 1
APPENDIX 2
APPENDIX 3
APPENDIX 4
SUSO
D+
D-
VB
XCVR
USB
CONTROLLER
DEVICE
CNTL
PWR
USB
VD
DESC
ROM
USB
SUMMARY
DC and AC specifications
HW application example
CONTROL COMMANDS—USB setup packet encoding
COMMUNICATION COMMANDS—USB setup packet
encoding
MODE COMMANDS—USB setup packet encoding
USB command and command type constant codes
FUNCTION
1-WIRE
CORE
USB
3 of 50
XI
OSC
XO
FIFOS
GEN
CLK
EP
GND
CONTROLLER
1-WIRE
VD2
VPP
I/F
1-WIRE