SIRECT L054BT26

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L054BT26
Low Capacitance Surface Mount TVS Diodes
FEATURES
• Four ultra-low input capacitance ( 1 pF typ.)
ESD rail-to-rail protection diodes
• ESD IEC 61000-4-2 level 4, ± 8kV contact
Discharge compliant protection
• Low voltage clamping due to integrated
Zener diode
• Compact SOT-23-6 package
APPLICATION
General-purpose downstream ESD protection
high frequency analog signals and high-speed
serial data transmission for ports inside:
• PC-/Notebook USB2.0/IEEE1394 ports
• Cellular phone and PCS mobile handsets
• DVI interfaces
• Cordless telephones
• Wireless data (WAN/LAN) systems
• PDAs
The L054BT26 devices are low-capacitance
transient voltage suppressors designed to
protect components which are connected to
data and transmission lines from over
voltages caused by electrostatic discharge
(ESD), electrical fast transients (EFT), and
induced lightning.
SCHEMATIC & PINNING (SOT23-6)
CIRCUIT DIAGRAM
MAXIMUM RATINGS
SYMBOL
MIN
MAX
UNIT
DC input voltage range
RATING
VI/O
0
+5.5
Volts
Electrostatic Discharge, all pins (IEC 61000-4-2, Level 4, Contact)
ESD
-8
+8
KiloVolts
Device Storage Temperature
Tstg
-55
+125
ELECTRICAL CHARACTERISTICS
PARAMETER
Pin capacitance to ground,
Pins 1, 3, 4, 6
Diode reverse leakage current,
Pins 1, 3, 4, 6 to ground
Zener diode capacitance to
ground, Pin 5 to 2
Zener diode breakdown voltage,
Pin 5 to 2
Forward voltage
o
C
o
TC = 25 C unless otherwise specified
TEST CONDITIONS
SYMBOL
MIN
TYP
MAX
UNIT
Vdc = 0V; f = 1 MHz
Pin 5 = +3.0V
CI/O
-
1.0
-
pF
V = +3.0V
Ilkg
-
-
100
nA
Vdc = 0V; f = 1 MHz
Pin 5 = +3.0V
CZener
-
40
-
pF
I = 1mA
VBR I/O
6
-
9
V
VF
-
0.7
-
V
August 2007 / Rev.5
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L054BT26
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L054BT26
APPLICATION INFORMATION
1.0 Four High-Speed Data Lines Protection
The L054BT26 TVS diode is designed to protect up to four data lines from transient over-voltages by
clamping them to a fixed reference. When the voltage on the protected line(s) exceeds the reference
voltage (plus diode VF), the steering diodes are forward biased, conducting the transient current away
from the protected circuitry. The data lines are connected to pins 1, 2, 4 and 6. The negative reference
(REF1) is connected to pin 2 (This pin should be connected directly to the ground plane on the PCB for
best results). The path length is kept as short as possible to minimize parasitic inductance. The
positive reference (REF2) is connected to pin 5.
The typical options for connecting the positive reference are as follows:
A. DATA LINE AND POWER SUPPLY PROTECTION USING VCC AS REFERENCE
To protected data lines and the power line, connect pin 5 directly to the positive supply rail (VCC).
In this configuration, the data lines are referenced to the supply voltage. The internal TVS diode
prevents over-voltage on the supply rail.
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L054BT26
APPLICATION INFORMATION (continued)
B. DATA LINE PROTECTION WITH BIAS AND POWER SUPPLY ISOLATION RESISTOR
The L054BT26 can be isolated from the power supply by adding a series resistor between pin 5 and
VCC (A resistor value of 100kΩ is recommended). The internal TVS and steering diodes remain
biased, providing the advance of even lower capacitance.
C. DATA LINE PROTECTION USING INTERNAL TVS DIODE AS REFERENCE
In applications where no positive supply reference is available, or complete supply isolation is desired,
the internal TVS may be used as the reference. In this case, pin 5 is not used. The steering diodes
will begin to conduct when the voltage on the protected line exceeds the working voltage of the TVS
(plus one diode drop).
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L054BT26
APPLICATION INFORMATION (continued)
2.0 Universal Serial Bus (USB) ESD Protection
The L054BT26 can be used to protect the USB ports on mobile phones, monitors, PCs, peripherals
and other portable systems (please refer to schematic diagram below). In typical applications, the
voltage bus (VBUS) of USB ports are connected to the power pin (pin 5) of the device. Each data line
(D+/D-) of the USB ports is connected to the ESD protection pin of the device.
When an electrostatic discharge (ESD) pulse appears on the data line, the ESD pulse current will be
conducted by the L054BT26 away from the USB controller chip. In addition, the ESD pulse current
can also be conducted by the device away from the USB controller chip when the ESD voltage pulse
appears on the voltage bus (VBUS) of any of the USB ports. Therefore, the data lines (D+/D-) and
voltage bus (VBUS) of the two USB ports are complementally protected with the L054BT26 device.
Typical Universal Serial Bus 2.0 Serial Application of the L054BT26
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L054BT26
APPLICATION INFORMATION (continued)
3.0 Audio interface ESD Protection
Another typical application of the L054BT26 is ESD protection of the Right/Left channel and TMC
terminals of an audio interface. Referring to the schematic diagram below, the Right and Left
channels of the audio connector are connected to the ESD protection pins (such as pin 1 and pin 6)
of the L054BT26. In addition, the TMC terminals of the audio connector are also connected to the
ESD protection pins (such as pin 3 and pin 4) of the device. Regarding the power pin (pin 5) of the
device, this should be directly connected to the VDD power supply.
In this configuration, when an electrostatic discharge (ESD) voltage pulse appears on the Right or
Left channel or TMC terminals of audio connector, the ESD pulse current will automatically be
discharged by by the L054BT26. Therefore, the Right/Left channel and TMC terminals of the audio
chip are complementally protected with an L054BT26 device.
Typical Audio Interface Application of the L054BT26
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L054BT26
APPLICATION INFORMATION (continued)
4.0 Other Applications
DVI/HDMI Digital Single Link ESD Protection
T1/E1/Ethernet ESD Protection
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L054BT26
PACKAGE DRAWING
MARKING CODES
Part Number
Marking Code
L054BT26
5V4
Sirectifier Global Corp., Delaware, U.S.A.
U.S.A.: [email protected] France: [email protected] Taiwan: [email protected] Hong Kong: [email protected]
China: [email protected] …Thailand: [email protected] Philippines: [email protected] Belize: [email protected]
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