PACUSB-U1/U2/U3
Upstream USB Port Terminator
Features
•
•
•
•
•
One upstream USB port terminator, EMI filter and
transient overvoltage protector in a single surface-
mount package
Compact SC70 or SOT23 package saves board
space and lowers manufacturing costs compared
to discrete solutions
ESD protection to
±30kV
contact discharge per
MIL-STD-883D, method 3015
ESD protection to
±15kV
contact discharge per
IEC 61000-4-2 international standard
Lead-free version available
Product Description
The PACUSB-U1, PACUSB-U2, and PACUSB-U3 are
single-channel USB upstream-port termination net-
works.
The PACUSB-U1/U2/U3 integrate EMI/RFI filter com-
ponents R1 and C1, as recommended by the USB
specification. Because these are upstream USB
devices, they are terminated with a single 1.5kΩ pull-up
resistor to V
3.3
(R2).
There are three options for the value of the series
resistor R1:
• For PACUSB-U1, R1=15Ω
• For PACUSB-U2, R1=33Ω
• For PACUSB-U3, R1=22Ω
This series resistance plus the USB driver output resis-
tance must be close to the USB cable’s characteristic
impedance of 45Ω (90Ω balanced) to minimize trans-
mission line reflections.
In addition, these parts provide a very high level of pro-
tection for sensitive electronic components that may be
subjected to electrostatic discharge (ESD). The input
and output pins are designed and characterized to dis-
sipate ESD strikes of
±15kV
safely, a level well beyond
the maximum requirements of the IEC 61000-4-2 inter-
national standard.
Using the MIL-STD-883D (Method 3015) specification
for Human Body Model (HBM) ESD, all pins are pro-
tected for contact discharges to greater than
±30kV.
The PACUSB-U1/U2/U3 is housed in either a 6-pin
SC70 or 6-pin SOT23 package and is available with
optional lead-free finishing.
Applications
•
•
•
•
•
•
•
ESD protection and termination of USB port
All USB peripherals (PC printers, scanners,
zip drives, etc.)
PDAs / handheld PCs
Digital cameras
Wireless Handets
MP3 Players
Cable Modems
Electrical Schematic
1
D1_i
IN1
R1
C1
R2
6
D1_c
OUT 1
i = input
c = connector
5
V
3.3
Vcc
GND
GND
2
C1
3
R1
SC70 6
© 2006 California Micro Devices Corp. All rights reserved.
05/01/06
D2_i
IN2
4
D2_c
OUT 2
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
●
Fax: 408.263.7846
●
www.cmd.com
1
CALMIRCO [ CALIFORNIA MICRO DEVICES CORP ]
