DALC208

Technical information

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Figure 8.

ESD behavior: parasitic phenomena due to unsuitable layout

2.3

How to ensure good ESD protection

While the DALC208SC6 provides a high immunity to ESD surge, an efficient protection

depends on the layout of the board. In the same way, with the rail to rail topology, the track

from the V

as possible to avoid over voltages due to parasitic phenomena. See Figure 8.

It’s often harder to connect the power supply near to the DALC208SC6 unlike the ground

thanks to the ground plane that allows a short connection.

To ensure the same efficiency for positive surges when the connections can’t be short

enough, we recommend putting a capacitance of 100 nF close to the DALC208SC6,

between V

See Figure 9.

The addition of this capacitance will allow a better protection by providing a constant voltage

during a surge.

Figure 10, Figure 11, and Figure 12 show the improvement of the ESD protection according

to the recommendations described above.

Lw

VI/O

ESD

SURGE

REF1=GND

I/O

REF2=+Vcc

Vf

Lw di

dt

Lw di

dt

Vcl+ = Vcc+Vf+Lw

di

dt

surge >0

-Vf- Lw

di

dt

surge <0

Vcl- =

t

tr=1ns

Vcc+Vf

Lw di

dt

Vcl+

POSITIVE

SURGE

167V

-Lw

di

dt

t

tr=1ns

-Vf

Vcl-

NEGATIVE

SURGE

-162V