AN820 APPLICATION NOTE

2/5

Figure 2 shows a circuit using an input/output clamping protection array. Two types of clamping array de-

vices are today available depending on the energy involved.

– If only ESD can occur the ESDA series is required.

Note: 1. ,More energetic than the ESD surges.

Figure 2. Input / Output protection by clamping device

PROTECTION BY DIODE ARRAY

Figure 3 shows the topology of the protection by diodes to the ground and to the supply rail.

The result of this protection circuit when positive or negative surges occur is similar to the previous one.

The only difference is where the surge energy is absorbed.

Figure 3. Circuit of protection by diodes and characteristics

Figure 4 shows an input/output protection by diode array circuit of the DA series.

INPUT

or

OUTPUT

µC

I

V

V

SUPPLY

SUPPLY RAIL

V

VF