SRDA3.3-4
Final Datasheet Rev 3.2
05/22/2019
www.semtech.com 1
Semtech
Proprietary & Condential
SRDA3.3-4
PROTECTION PRODUCTS
Features
• Transient protection for high-speed data lines to
IEC 61000-4-2 (ESD) ±15kV (air), ±8kV (contact)
IEC 61000-4-4 (EFT) 40A (5/50ns)
IEC 61000-4-5 (Lightning) 25A (8/20μs)
• Array of surge rated diodes with internal TVS diode
• Protects four I/O lines
• Low capacitance (<15pF)
• Low operating voltage: 3.3V
• Low clamping voltage
• Solid-state technology
Mechanical Characteristics
• JEDEC SOIC-8 Package
• Pb-Free, Halogen Free, RoHS/WEEE Compliant
• Lead Finish: Matte Sn
• Marking : Marking Code
• Packaging : Tape and Reel
Applications
• T1/E1 secondary IC Side Protection
• T3/E3 secondary IC Side Protection
• Analog Video Protection
• Microcontroller Input Protection
• Base stations
• I2C Bus Protection
Circuit Diagram Schematic and Pin Conguration
RailClamp®
Low Capacitance TVS Array
SO-8 (Top View)
Description
RailClamp® TVS arrays are low capacitance ESD protection
devices designed to protect sensitive components from
overvoltage caused by electrostatic discharge (ESD),
electrical fast transients (EFT), and lightning surge. They
oers desirable characteristics for board level protection
including fast response time, low operating and clamping
voltage, and no device degradation.
The unique design incorporates surge rated, low
capacitance steering diodes and a TVS diode in a single
package. During transient conditions, the steering diodes
direct the transient current to ground via the internal low
voltage TVS. The TVS diode clamps the transient voltage
to a safe level. The low capacitance array conguration
allows the user to protect up to four data lines.
The SRDA3.3-4 is constructed using Semtech’s proprietary
EPD process technology. The EPD process provides low
stand-o voltages with signicant reductions in leakage
current and capacitance over silicon avalanche diode
processes. They feature a true operating voltage of 3.3
volts for superior protection. These devices are in a 8-pin
SOIC package. It measures 3.9 x 4.9mm. The high surge
capability (IPP=25A, tp=8/20μs) means it can be used in
high threat environments in applications such as CO/CPE
equipment, telecommunication lines, and video lines.
I/O 1
5, 8
2, 3
I/O 2 I/O 3 I/O 4
1
2
3
4
8
7
6
5
I/O 1
I/O 2
I/O 3
I/O 4
NC
NC
GND
GND
SRDA3.3-4
Final Datasheet Rev 3.2
05/22/2019
www.semtech.com 2
Semtech
Proprietary & Condential
Absolute Maximum Ratings
Electrical Characteristics (T=25OC unless otherwise specied)
Rating Symbol Value Units
Peak Pulse Power (tp = 8/20µs) PPK 500 W
Peak Pulse Current (tp = 8/20µs) IPP 25 A
Lead Soldering Temperature TL260 (10 sec.) °C
Operating Temperature TOP -40 to +85 °C
Storage Temperature TSTG -55 to +150 °C
Parameter Symbol Conditions Min. Typ. Max. Units
Reverse Stand-O Voltage VRWM 3.3 V
Punch-Through Voltage VPT IPT = 2µA 3.5 V
Snap-Back Voltage VSB ISB = 50mA 2.8 V
Reverse Leakage Current IRVRWM = 3.3V 1 µA
Clamping Voltage VCtp = 8/20µs
IPP = 1A 5.3
VIPP = 10A 10
IPP = 25A 15
Junction Capacitance CJVR = 0V, f = 1MHz
I/O to GND 8 15
pF
I/O to I/O 4
SRDA3.3-4
Final Datasheet Rev 3.2
05/22/2019
www.semtech.com 3
Semtech
Proprietary & Condential
Typical Characteristics
Non-Repetitive Peak Pulse Power vs. Pulse Time Power De-rating Curve
Clamping Voltage vs. Peak Pulse Current
0
2
4
6
8
10
12
14
16
18
20
0 5 10 15 20 25 30
Clamping Voltage (V)
Peak Pulse Current - IPP (A)
Waveform
Parameters:
tr = 8µs
td = 20µs
0.8
0.9
1
1.1
1.2
0 0.5 1 1.5 22.5 3 3.5
Normalized Capacitance - CJ(V
R
) /C
J
(V
R
=0V)
Reverse Voltage - V
R
(V)
f = 1 MHz
0.01
0.1
1
10
0.1 1 10 100 1000
Peak Pulse Power - P
PP
(kW)
Pulse Duration - tp (µs)
TA = 25OC
0
20
40
60
80
100
120
0 25 50 75 100 125 150
% of Rated Power or I
PP
Ambient Temperature - TA (
O
C)
DR040514-25-125-150
Normalized Junction Capacitance vs. Reverse Voltage
SRDA3.3-4
Final Datasheet Rev 3.2
05/22/2019
www.semtech.com 4
Semtech
Proprietary & Condential
Application Information
Device Connection Options for Protection of Four
High-Speed Data Lines
These devices are designed to protect low voltage data
lines operating at 3.3V. When the voltage on the protected
line exceeds the punch-through or “turn-on” voltage of
the TVS diode, the steering diodes are forward biased,
conducting the transient current away from the sensitive
circuitry.
Data lines are connected at pins 1, 4, 6 and 7. Pins 5 and 8
should be connected directly to a ground plane. The path
length is kept as short as possible to minimize parasitic
inductance.
Note that pins 2 and 3 are connected internally to the
cathode of the low voltage TVS. It is not recommended
that these pins be directly connected to a DC source
greater than the snap-back voltage (VSB) as the device
can latch on as described below.
EPD TVS IV Characteristic Curve
These devices are constructed using Semtech’s proprietary
EPD technology. By utilizing the EPD technology, the
SRDA3.3-4 can eectively operate at 3.3V while maintaining
excellent electrical characteristics.
The EPD TVS employs a complex nppn structure in
contrast to the pn structure normally found in traditional
silicon-avalanche TVS diodes. Since the EPD TVS devices
Data Line Protection Using Internal TVS Diode as Reference
IR
IPP
VC
VPT
VSB
VRWM
ISB
IPT
VBR
IBR
use a 4-layer structure, they exhibit a slightly dierent
IV characteristic curve when compared to conventional
devices. During normal operation, the device represents
a high-impedance to the circuit up to the device working
voltage (VRWM). During an ESD event, the device will
begin to conduct and will enter a low impedance state
when the punch through voltage (VPT) is exceeded.
Unlike a conventional device, the low voltage TVS will
exhibit a slight negative resistance characteristic as it
conducts current. This characteristic aids in lowering the
clamping voltage of the device, but must be considered
in applications where DC voltages are present.
When the TVS is conducting current, it will exhibit a slight
“snap-back” or negative resistance characteristics due to
its structure. This point is dened on the curve by the
snap-back voltage (VSB) and snap-back current (ISB). To
return to a non-conducting state, the current through the
device must fall below the ISB (approximately <50mA) and
the voltage must fall below the VSB (normally 2.8V for a
3.3V device). If a 3.3V TVS is connected to 3.3V DC source,
it will never fall below the snap-back voltage of 2.8V and
will therefore stay in a conducting state.
EPD TVS IV Characteristic Curve
1
2
3
4
8
7
6
5
I/O 1
NC
NC
I/O 2
I/O 3
I/O 4
SRDA3.3-4
Final Datasheet Rev 3.2
05/22/2019
www.semtech.com 5
Semtech
Proprietary & Condential
Typical Application
RTIP
RRING
TTIP
TRING
T1/E1
Transceiver
R1
R3
R2
T1
T2
LC01-6
LC01-6
SRDA 3.3-4
14
5
8
PTC
PTC
PTC
PTC
R4
R5
T1/E1 Interface Protection (GR-1089 Long Haul)
SRDA3.3-4
Final Datasheet Rev 3.2
05/22/2019
www.semtech.com 6
Semtech
Proprietary & Condential
Outline Drawing - SO-8
Land Pattern - SO-8
8
0.25
1.27 BSC
6.00
3.90
4.90
-
3.80
4.80
0.39
4.00
5.00
0.47
0°
0.20
0.10
-8°
0.50
0.20
1.30
0.10
-
(1.05)
-
-
0.80
0.24
1.40
-
-1.75
1.50
0.225
0.25 0.50
-
3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS.
CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
DATUMS AND TO BE DETERMINED AT DATUM PLANE .
NOTES:
1.
2.
L1
N
01
bbb
aaa
ccc
A
b
A2
A1
D
E
E1
L
h
e
c
DIM MIN
MILLIMETERS
DIMENSIONS
MAXNOM
-B--A- -H-
REFERENCE JEDEC STD MS-012, VARIATION AA.
4.
DETAIL A
bxN
2X N/2 TIP S
SEATING
aaa C
E/2
2X
1 2
N
A
D
A1
E1
bbb C A-B D
ccc C
e/2
A2
c
L
(L1) 01
0.25
H
GAGE
PLANE
h
A
B
C
D
e
PLANE
SEE DETAIL A
SID E VIEW
E5.80 6.20
(5.20)
Z
G
Y
P
(C) 3.00
1.27
0.60
2.20
7.40
X
DIMENSIONS
Z
P
Y
X
DIM
C
G
MILLIMETERS
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
NOTES:
1.
REFERENCE IPC-SM-782A, RLP NO. 300A.2.
SRDA3.3-4
Final Datasheet Rev 3.2
05/22/2019
www.semtech.com 7
Semtech
Proprietary & Condential
Marking Code
Tape and Reel Specication
Ordering Information
Part Number Lead Finish Qty per Reel Reel Size
SRDA3.3-4.TLT Matte Sn 3000 13 Inch
SC YYWW
SRDA3.3-4
XXXXX
Notes:
YYWW = Date Code
XXXXX = Country of Assembly
SC YYWW
SRDA3.3-4
XXXXX
SC YYWW
SRDA3.3-4
XXXXX
Pin 1 Location
User Direction of Feed
SRDA3.3-4
Final Datasheet Rev 3.2
05/22/2019
8
Semtech
Contact Information
Semtech Corporation
200 Flynn Road, Camarillo, CA 93012
Phone: (805) 498-2111, Fax: (805) 498-3804
www.semtech.com
Important Notice
Information relating to this product and the application or design described herein is believed to be reliable, however such information is provided
as a guide only and Semtech assumes no liability for any errors in this document, or for the application or design described herein. Semtech reserves
the right to make changes to the product or this document at any time without notice. Buyers should obtain the latest relevant information before
placing orders and should verify that such information is current and complete. Semtech warrants performance of its products to the specications
applicable at the time of sale, and all sales are made in accordance with Semtech’s standard terms and conditions of sale.
SEMTECH PRODUCTS ARE NOT DESIGNED, INTENDED, AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT APPLICATIONS,
DEVICES OR SYSTEMS, OR IN NUCLEAR APPLICATIONS IN WHICH THE FAILURE COULD BE REASONABLY EXPECTED TO RESULT IN PERSONAL INJURY,
LOSS OF LIFE OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. INCLUSION OF SEMTECH PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD
TO BE UNDERTAKEN SOLELY AT THE CUSTOMER’S OWN RISK. Should a customer purchase or use Semtech products for any such unauthorized
application, the customer shall indemnify and hold Semtech and its ocers, employees, subsidiaries, aliates, and distributors harmless against
all claims, costs damages and attorney fees which could arise.
The Semtech name and logo are registered trademarks of the Semtech Corporation. All other trademarks and trade names mentioned may be
marks and names of Semtech or their respective companies. Semtech reserves the right to make changes to, or discontinue any products described
in this document without further notice. Semtech makes no warranty, representation or guarantee, express or implied, regarding the suitability of
its products for any particular purpose. All rights reserved.
© Semtech 2019
Proprietary & Condential