CM1214A
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APPLICATION INFORMATION
CM1214A−01SO
The CM1214A−01SO protects a single bipolar signal line often found in RF circuits. One I/O pin (pin 1 for example) is
connected to the signal line for protection, and the other I/O pin is tied to GND. It is important to have a solid ground connection
to reduce the clamping voltage. Pin 3 of the 3−lead SOT23 must be left open (and not connected on the PCB).
CM1214A−02MR
The CM1214A−02MR protects two bipolar lines, such as for Gbit Ethernet. The PCB traces underneath the package connect
across to the corresponding pins (Pins 1, 4, 6 and 7). Pins 2, 3, 5 and 8 of the MSOP−8 package must be left open (and not
connected on the PCB).
Any disturbance on the line above or below the standoff voltage is clamped.
RF ANTENNA
SIGNAL LINE
SWITCH
ESD
N.C.
GND
ESD
SOT23−3
LNA
PA
L
C
Figure 7. Typical Application − RF Switch and Amplifier Protection,
CM1214A−01SO in 3−lead SOT23
CH1
CH2
CH3
CH4
FROM
ASIC
TO CONNECTOR
RX−
RX+
TX−
TX+
CM1214A−02MRCM1214A−02MR
Figure 8. Typical Application − Ethernet Protection,
CM1214A−02MR in 8−lead MSOP
