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PROTECTION PRODUCTS
RClamp2451Y
Applications Information
Figure 1 - NFC Protection Example
ESD Protection of NFC Interfaces
The Near Field Communication (NFC) antenna is
usually connected to the NFC controller IC via contact
points on the phone. These contact points are user
accessable and therefore may be subjected to ESD
strikes. External protection (TVS) devices should be
placed between the antenna and the NFC chip inter-
face. The working voltage of the TVS should be high
enough as not to clip the NFC signal. Additionaly, the
capacitance of the device should be minimized in order
to avoid harmonic disctortion of the RF signal.
RClamp2451Y meets these requirements and also
features extremely low dynamic resistance (<0.1
Ohms) resulting in low ESD clamping voltage. The low
dynamic resistance also helps insure protection for
Schottky diodes that may be used in the NFC circuit.
RClamp2451Y is designed to work on NFC circuits with
AC signals as high as 24V. An example protection ciruit
using RClamp2451Y is shown below in Figure 1.
TX+
TX-
REC
RClamp2451Y
RClamp2451Y
Antenna+
Antenna -
GND
NFC
Controller
Antenna
Matching
Ckt
EMI Filter
Ckt
Antenna
Matching
Ckt
EMI Filter
Ckt
RX+ RX-
C
R
