NUP4201DR2
APPLICATIONS INFORMATION
The new NUP4201DR2 device is a low capacitance TVS
Option 2
Diode array designed to protect sensitive electronics such as
communications systems, computers, and computer
peripherals against damage due to ESD conditions or
transient voltage conditions. Because of its low capacitance
array configuration, it can be used in high speed I/O data
lines.
Four Data lines protection with Bias and power supply
isolation resistor.
I/O 1
I/O 2
V
CC
1
2
3
4
The integrated design of the NUP4201DR2 device offers
surge rated, low capacitance steering diodes and a TVS
diode integrated in a single package (SO−8). If a transient
condition occurs, the steering diodes will drive the transient
condition to the positive polarity of the power supply or to
ground. The TVS device protects the power line against
over−voltage conditions to avoid damage in any
downstream components.
8
7
10 K
6
5
I/O 3
I/O 4
The NUP4201DR2 device can be isolated from the power
supply by connecting a series resistor between pins 2 & 3 and
Vcc. A resistor of 10KW is recommended for isolation
purposes. The internal TVS and steering diodes remain
biased, which provides the advantage of lower capacitance.
NUP4201DR2 Device’s Configurations Options
The NUP4201DR2 is able to protect up to four data lines
against transient over−voltage conditions by driving them to
a fixed reference point for clamping purposes. The steering
diodes will be forward biased whenever the voltage on the
protected line exceeds the reference voltage (Vcc+Vf). The
diodes will drive the transient current away from the
sensitive circuit.
Data lines are connected at pins 1,4,6 and 7. The negative
reference is connected at pins 5 and 8. These pins must be
connected directly to ground by using a ground plane to
minimize the PCB’s ground inductance. It is very important
to reduce as much as possible the PCB trace lengths to
minimize parasitic inductances.
Option 3
Four Data lines protection using internal TVS diode as
reference.
I/O 1
I/O 2
1
2
3
4
8
7
NC
NC
Option 1
6
5
Four Data lines protection and power supply protection
using Vcc as reference.
I/O 3
I/O 4
I/O 1
I/O 2
In the case of applications in which a positive supply
reference is not available or full isolation is required, the
internal TVS could be used as the reference, so for this
purpose, the pins 2 and 3 are not connected. In this case, the
steering diodes will conduct whenever the voltage on the
protected line exceeds the working voltage of the TVS plus
one diode drop (Vc=Vf + VTVS).
1
2
3
4
8
7
V
CC
6
5
I/O 3
I/O 4
For this configuration, connect pins 2 & 3 directly to the
positive supply rail (Vcc), the data lines are referenced to the
supply voltage. The internal TVS diode prevents
over−voltage on the supply rail.
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