RCLAMP0544T.TCT Semtech, RCLAMP0544T.TCT Datasheet - Page 5

• Manufacturer Part Number: RCLAMP0544T.TCT
• Description: RClamp Low Profile, Ultra Low Cap TVS For Portable Applications
• Manufacturer: Semtech

Specifications of RCLAMP0544T.TCT

• Lead Free Status / Rohs Status: Supplier Unconfirmed

Design Recommendations for HDMI Protection
Adding external ESD protection to HDMI ports can be
challenging. First, ESD protection devices have an
inherent junction capacitance. When adding even a
small amount of capacitance, it will cause the
impedance of the differential pair to drop. Second,
large packages and land pattern requirements can
cause discontinuities that adversely affect signal
integrity. The RClamp0544T is specifically designed for
protection of high-speed interfaces, such as HDMI. It
presents <0.3pF capacitance between the pairs while
being rated to handle >±8kV ESD contact discharges
(>±15kV air discharge) as outlined in IEC 61000-4-2.
The device is in a leadless SLP package that is less
than 1.1mm wide. It is designed such that the traces
flow straight through the device. The narrow package
and flow-through design reduce discontinuities and
minimize impact on signal integrity. This becomes even
more critical as signal speeds increase.
Pin Configuration
Figure 2 is an example of how to route the high speed
differential traces through the RClamp0544T. The PCB
traces are used to connect the pin pairs for each line
(pin 1 to pin 8, pin 2 to pin 7, pin 3 to pin 6, pin 4 to
pin 5). For example, line 1 enters at pin 1 and exits at
Pin 8, and the PCB trace connects pin 1 and 8 to-
gether. This is true for lines connected at pins 2, 3,
and 4 also. Note that there are no internal connec-
tions to pins 5 - 8. Ground is connected at the center
tabs. One large ground pad should be used in lieu of
two separate pads.
TDR Measurements for HDMI
The combination of low capacitance, small package,
and flow-through design means it is possible to use
these devices to meet the HDMI impedance require-
ments of 100 Ohm ±15% without any PCB board
modification.
For signal integrity purposes, the best results will be
obtained by using the RClamp0544T to protect the
high-speed differential pairs. This is because the
device is designed such that the data lines from the
connector line up with the I/O pins of the device
without altering the trace routing.
PROTECTION PRODUCTS
© 2011 Semtech Corp.
Applications Information
5
Figure 1 - SLP2010P8T Pin Configuration (Top View)
Figure 2 - Flow through Layout Using
Figure 2 - Flow through Layout Using
Figure 2 - Flow through Layout Using
Figure 2 - Flow through Layout Using
Figure 2 - Flow through Layout Using
C
, 1
, 5
e
t n
, 6
, 2
P
r e
n i
, 3
, 7
Input 1
Input 2
Input 3
Input 4
T
b a
4
8
RClamp0544T
RClamp0544T
RClamp0544T
RClamp0544T
RClamp0544T
1
2
3
4
N (
GND
o
n I
RClamp0544T
d I
8
7
6
5
O
e t
n I
e
u
n r
p
n
p t
r G
t u
NC
NC
NC
NC
f i t
l a
t u
u o
c i
C
L
n
L
t a
n o
n i
PRELIMINARY
n i
d
o i
s e
s e
n
e
n
www.semtech.com
t c
o i
) n