UCLAMP3301H.TCT Semtech, UCLAMP3301H.TCT Datasheet - Page 4

• Manufacturer Part Number: UCLAMP3301H.TCT
• Description: IC TVS ESD 1-LINE 3.3V SOD-523
• Manufacturer: Semtech
• Series: µClamp™r

Specifications of UCLAMP3301H.TCT

• Voltage - Reverse Standoff (typ): 3.3V
• Voltage - Breakdown: 4.5V
• Power (watts): 40W
• Polarization: Bidirectional
• Mounting Type: Surface Mount
• Package / Case: SOD-523
• Applications: General Purpose
• Number Of Circuits: 1
• Voltage - Working: 3.3V
• Voltage - Clamping: 5.5V
• Technology: Diode Array
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: UCLAMP3301HTR

Device Connection Options
The μClamp3301H is designed to protect one I/O, or
power supply line. It will present a high impedance to
the protected line up to 3.3 volts. It will “turn on”
when the line voltage exceeds 3.5 volts. The device is
unidirectional and may be used on lines where the
signal polarity is above ground. The cathode band
should be placed towards the line that is to be
protected.
Due to the “snap-back” characteristics of the low
voltage TVS, it is not recommended that the I/O line be
directly connected to a DC source greater than snap-
back votlage (V
described below.
EPD TVS Characteristics
The μClamp3301H is constructed using Semtech’s
proprietary EPD technology. The structure of the EPD
TVS is vastly different from the traditional pn-junction
devices. At voltages below 5V, high leakage current
and junction capacitance render conventional ava-
lanche technology impractical for most applications.
However, by utilizing the EPD technology, the
μClamp3301H can effectively 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 tradi-
tional silicon-avalanche TVS diodes. Since the EPD
TVS devices use a 4-layer structure, they exhibit a
slightly different 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 (V
event, the device will begin to conduct and will enter a
low impedance state when the punch through voltage
(V
voltage TVS will exhibit a slight negative resistance
characteristic as it conducts current. This characteris-
tic 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 characteris-
tics due to its structures. This point is defined on the
curve by the snap-back voltage (V
PROTECTION PRODUCTS
© 2008 Semtech Corp.
Applications Information
PT
) is exceeded. Unlike a conventional device, the low
SB
) as the device can latch on as
RWM
). During an ESD
SB
) and snap-back
4
current (I
current through the device must fall below the I
(approximately <50mA) and the voltage must fall below
the V
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.
SB
(normally 2.8 volts for a 3.3V device). If a 3.3V
Device Schematic & Pin Configuration
SB
). To return to a non-conducting state, the
EPD TVS IV Characteristic Curve
V
F
I
I
I
I
SB
PT
PP
R
uClamp3301H
I
F
V
RWM
www.semtech.com
V
SB
V
PT
V
C
SB