PROTECTION PRODUCTS
1
www.semtech.com
PRELIMINARY
PROTECTION PRODUCTS - RailClamp
®®
®®
®
RClamp1644T
Low Capacitance RClamp
®
ESD Protection for uUSB Interfaces
Description
Features
Circuit Diagram Pin Configuration
Revision 4/12/2012
Applications
Mechanical Characteristics
ESD protection for high-speed data lines to
IEC 61000-4-2 (ESD) ±25kV (air), ±20kV (contact)
IEC 61000-4-5 (Lightning) 10A (8/20μs)
IEC 61000-4-4 (EFT) 40A (5/50ns)
Protects USB DP, DM, and ID Pin operating to 5V
Protects USB VBus operating up to 12V
Low capacitance (<0.60pF) on DP, DM, and ID Pins
Low clamping voltage
Extremely low dynamic resistance: 0.33 Ohms (Typ)
on DP, DM, and ID Pins
Innovative flow-through design allows easy pcb
layout
Solid-state silicon-avalanche technology
RailClamp
®
is a low capacitance TVS array designed to
protect high speed data interfaces. This series has
been specifically designed to protect sensitive compo-
nents which are connected to data and transmission
lines from overvoltage caused by ESD (electrostatic
discharge), CDE (Cable Discharge Events), and EFT
(electrical fast transients).
The RClamp1644T is specifically designed to protect
portable devices that utilize a uUSB port. The unique
design of this device features low capacitance TVS
diodes for protection of the USB data (DP, DM) and
USB ID pins operating up to 5 volts. Loading capaci-
tance on these lines is <0.6pF for maximum signal
integrity. An integrated 12 volt TVS diode is used for
protection of the USB voltage bus. This ensures the
device will remain in a high-impedance state during
normal USB operation or when the battery is being
charged. Leakage current of the VBus protection is
<50nA when operating at 12 volts.
The RClamp1644T is in a 6-pin SLP1508N5T package.
It measures 1.5 x 0.8 x 0.40mm. The leads are
spaced at a pitch of 0.35mm and are finished with
lead-free NiPdAu. They may be used to meet the ESD
immunity requirements of IEC 61000-4-2.
USB 2.0
USB OTG
Micro USB
SLP1508N5T 5L package
Pb-Free, Halogen Free, RoHS/WEEE Compliant
Nominal Dimensions: 1.5 x 0.8 x 0.40 mm
Lead Finish: NiPdAu
Molding compound flammability rating: UL 94V-0
Marking : Marking code + date code
Packaging : Tape and Reel
SLP (Top View)
23 4
5
1
5V
12V
1
VBus
GND
DM
DP
ID
2
