Technical Reference Guide
Compaq iPAQ Family of Internet Devices
First Edition - March 2000
5-25
5.7.3 USB CONNECTOR
The USB interface p rovides two series-A connect ors on the front pan el and, on legacy-fr ee
models, three ser ies-A USB connectors on th e rear panel.
Figure 5-10. Universal Seria l Bus Connector
Table 517. USB Connector Pinout
Table 5-17.
USB Connector Pinout
Pin Signal Description Pin Signal Description
1 Vcc +5 VDC 3 USB+ Data (plus)
2 USB- Data (minus) 4 GND Ground
5.7.4 USB CABLE DATA
The recommended cable length between th e host and the USB device sh ould be no longer th an
sixteen feet for full -channel (12 MB/s) operation, depend ing on cable specificat ion (see following
table).
Table 518. USB Cable Length Data
Table 5-18.
USB Cable Length Data
Conductor Size R esistance Maximum Length
20 AWG 0.036 16.4 ft (5.00 m)
22 AWG 0.057 9.94 ft (3.03 m)
24 AWG 0.091 6.82 ft (2.08 m)
26 AWG 0.145 4.30 ft (1.31 m)
28 AWG 0.232 2.66 ft (0.81 m)
NOTE:
For sub-channel (1.5 MB/s) operation and/or when using sub- standard cable
shorter lengths may be allowable and/or necessary .
The shield, chassis ground, and power ground should be tied together at the host end but left
unconnected at the device end to avoid gr ound loops.
Color code:
Signal Insulation color
Data + Green
Data - White
Vcc Red
Ground Black
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