ESDAxxL
1. ESD protection by the ESDAxxL
Electrostatic discharge (ESD) is a major cause of
failure in electronic systems.
Transient Voltage Suppressors (TVS) are an ideal
choice for ESD protection. They are capable of
clamping the incoming transient to a low enough
level such that damage to the protected
semiconductor is prevented.
Surface mount TVS arrays offer the best choice for
minimal lead inductance.
They serve as parallel protection elements,
connected between the signal line to ground. As
the transient rises above the operating voltage of
the device, the TVS array becomes a low
impedance path diverting the transient current to
ground.
The ESDAxxL array is the ideal board level
protection of ESD sensitive semiconductor
components.
The tiny SOT23 package allows design flexibility in
the design of high density boards where the space
saving is at a premium. This enables to shorten the
routing and contributes to hardening againt ESD.
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ESD
sensitive
device
GND
2 * ESDAXXL
2. Circuit Board Layout
Circuit board layout is a critical design step in the
suppression of ESD induced transients. The
following guidelines are recommended :
n
The ESDAxxL should be placed as close as pos-
sible to the input terminals or connectors.
n
The path length between the ESD suppressor
and the protected line should be minimized
n
n
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All conductive loops, including power and
ground loops should be minimized
The ESD transient return path to ground should
be kept as short as possible.
Ground planes should be used whenever possi-
ble.
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