UESD6V8Lxx
Low Capacitance TVS Diode Array for ESD Protection
UESD6V8L4A
SC70-5/SC88A/SOT353
UESD6V8L4B
SC89-5/SOT553/SOT665
UESD6V8L5A6
SC70-6/SC88/SOT363
UESD6V8L5B
SC89-6/SOT563/SOT666
General Description
The UESD6V8Lxx of TVS diode array is designed to protect sensitive electronics from damage
or latch-up due to ESD, for use in applications where board space is at a premium. It is
unidirectional device and may be used on lines where the signal polarities are above ground.
UESD6V8L4A and UESD6V8L4B protect up to four lines while UESD6V8L5A6 and
UESD6V8L5B will protect up to five lines. TVS diodes are solid-state devices feature large
cross-sectional area junctions for conducting high transient currents, specifically for transient
suppression. It offers desirable characteristics for board level protection including fast response
time, low operating, low clamping voltage, and no device degradation. The UESD6V8Lxx may be
used to meet the immunity requirements of IEC 61000-4-2, level 4. The small package makes
them ideal for use in portable electronics such as cell phones, PDA’s, notebook computers, and
digital cameras. The UESD6V8Lxx is fabricated using dual diffusion technology, offer low
junction capacitance (20pF), which is required in high speed signal protection application.
.
Applications
Cellular Handsets & Accessories
Cordless Phones
Personal Digital Assistants (PDA’s)
Notebooks & Handhelds
Portable Instrumentation
Digital Cameras
Peripherals
MP3 Players
Features
Transient protection for data lines to
IEC 61000-4-2 (ESD) ±15kV (air), ±8kV
(contact)
Ultra-small package
Working Voltages: 5V
Low Leakage current
Low clamping voltage
Solid-state silicon avalanche technology
Ordering Information
Part Number
UESD6V8L4A
UESD6V8L4B
UESD6V8L5A6
UESD6V8L5B
5.0V
Working
Voltage
Packaging Type
SC70-5/SC88A/SOT353
SC89-5/SOT553/SOT665
SC70-6/SC88/SOT363
SC89-6/SOT563/SOT666
Channel
4
5
Marking
Code
UKA
USB
U6A
UB
Shipping
Qty
3000pcs/
7Inch Reel
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UESD6V8Lxx
Pin Configurations
1
2
3
5
1
2
5
1
2
6
5
4
1
2
3
6
5
4
4
3
4
3
UESD6V8L4A
SC70-5/SC88A/SOT353
UESD6V8L4B
SC89-5/SOT553/SOT665
UESD6V8L5A6
SC70-6/SC88/SOT363
UESD6V8L5B
SC89-6/SOT563/SOT666
Top View
M: Month Code
UESD6V8L4A
SC70-5/SC88A/SOT353
M: Month Code
UESD6V8L4B
SC89-5/SOT553/SOT665
M: Month Code
UESD6V8L5A6
SC70-6/SC88/SOT363
M: Month Code
UESD6V8L5B
SC89-6/SOT563/SOT666
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UESD6V8Lxx
Absolute Maximum Ratings
Rating
Peak Pulse Power (tp = 8/20μs)
Lead Soldering Temperature
Operating Temperature
Storage Temperature
Maximum Junction Temperature
Symbol
P
PK
T
L
T
J
T
STG
T
JMAX
Value
55
260(10 sec.)
-55 to +125
-55 to +125
150
Unit
Watts
°C
°C
°C
°C
Electrical Characteristics
Parameter
Reverse Stand-Off Voltage
Reverse Breakdown Voltage
Reverse Leakage Current
Clamping Voltage
Symbol
V
RWM
V
BR
I
R
V
C
It = 1mA
V
RWM
= 5V, T=25°C
I
PP
=1A, tp = 8/20μS
I
PP
=2A, tp = 8/20μS
I
PP
=5A, tp = 8/20μS
Junction Capacitance
Junction Capacitance
C
J
C
J
Pin 1,3,4,5,6 to 2
V
R
= 0V, f = 1MHz
Pin 1,3,4,5,6 to 2
V
R
= 2.5V, f = 1MHz
20
12
6
6.8
0.005
Conditions
Min
Typ
Max
5
7.2
0.1
6
8
10.8
25
17
pF
pF
V
Unit
V
V
μA
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UESD6V8Lxx
Typical Operating Characteristics
Non-Repetitive Peak Pulse Power vs. Pulse Time
10
Clamping Voltage vs. Peak Pulse Current
11
Peak Pulse Power - Ppk(kW)
10
1
Clamping Voltage - Vc (V)
9
8
0.1
7
Waveform
parameters:
tr=8uS
td=20uS
0
1
2
3
4
5
0.01
0.1
6
1
10
100
1000
Pulse Duration - tp(uS)
Peak Pulse Current - Ipp (A)
Forward Voltage vs. Forward Current
5.0
4.5
4.0
Junction Capacitance vs. Reverse Voltage
25
Forward Voltage-Vf(V)
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0
1
2
3
4
5
6
20
Capacitance-(pF)
15
10
5
0
0
1
2
3
4
5
Forward Current-If(A)
Revers Voltage-Vr(V)
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UESD6V8Lxx
Application Information
UESD6V8Lxx can use as unidirectional lines or bidirectional lines protector. For example,
UESD6V8L4B can use as a four unidirectional lines protector, and also can use as a three
bidirectional lines protector (as figure1 shows). For bidirectional applications, the junction
capacitance between I/O ports and ground is half of the single TVS’s junction capacitance, that is
to say the typical value of the junction capacitance between I/O ports and ground is 6pF. The
break down voltage of these two series connection TVS is a forwards voltage (about 0.7V) higher
than a single TVS’s.
Figure1: UESD6V8L4B use as three bidirectional lines protector
Circuit Board Layout Recommendations for Suppression of ESD
Good circuit board layout is critical for the suppression of ESD induced transients. The following
guidelines are recommended:
1. Place the TVS near the input terminals or connectors to restrict transient coupling.
2. Minimize the path length between the TVS and the protected line.
3. Minimize all conductive loops including power and ground loops.
4. The ESD transient return path to ground should be kept as short as possible.
5. Never run critical signals near board edges.
6. Use ground planes whenever possible. For multilayer printed-circuit boards, use ground
vias.
7. Keep parallel signal paths to a minimum.
8. Avoid running protection conductors in parallel with unprotected conductor.
9. Minimize all printed-circuit board conductive loops including power and ground loops.
10. Avoid using shared transient return paths to a common ground point.
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