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80-0276-F Datasheet, PDF (1/5 Pages) List of Unclassifed Manufacturers – System Level ESD Mitigation
System Level
ESD Mitigation
DESIGN NOTE
Introduction
The following is a list of industry best-practice suggestions that our research indicates may help improve
system-level ESD protection. You may wish to independently confirm these suggestions.
The suggestions have been broken down into four main categories, and the suggestions within each category
have been noted as follows:
(Recommended) – Potentially effective for little or no additional cost.
(Desirable) – Should be included in systems which can tolerate higher system cost (such set top boxes, etc)
Sensory highly recommends that this procedure be used to design and test ALL new product designs.
A. Making Your Circuits More Resistant To ESD:
1. (Recommended) Put clamp diodes such as 1N4148 (D1 and D2) and a 510 ohm series resistor (R3) and a
0.1 uF shunt capacitor (C10) in the microphone circuit as shown in Figure 1:
Microphone Input Section
RSC4x
R1 270
AVDD
R2
1.8K
C1 C2
220 .1
AVDD
C3 C4 C5 C6 C7 C8
2.2 .047 .1 1.0 .1 .1
MICROPHONE
R3 510
D1
1N4148
C9
C10
3300pF
.01
D2
1N4148
Figure 1 – Microphone ESD protection
2. (Recommended) Put 0.1uF capacitors across all pushbutton inputs.
3. (Recommended) Put 1K to 10K ohm series resistors on input signals if they travel to the outside or travel
long distances.
4. (Recommended) Put a 10K ohm series resistor and a 1N4148 diode to ground at the reset pin as shown in
Figure 2 if it travels to the outside (usually via a user reset pushbutton) or otherwise travels a long distance.
© 2006 Sensory Inc.
P/N 80-0276-F
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