KAI-4021 datasheet(15/56 Pages) ONSEMI

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KAI-4021 Image Sensor

www.truesenseimaging.com

Revision 1.1 PS-0014 Pg 15

ESD PROTECTION

Figure 7: ESD Protection

The ESD protection on the KAI-4021 is implemented using bipolar transistors. The substrate (VSUB) forms the

common collector of all the ESD protection transistors. The ESD pin is the common base of all the ESD protection

transistors. Each protected pin is connected to a separate emitter as shown in Figure 7: ESD Protection.

The ESD circuit turns on if the base-emitter junction voltage exceeds 17 V. Care must be taken while operating the

image sensor, especially during the power on sequence, to not forward bias the base-emitter or base-collector

junctions. If it is possible for the camera power up sequence to forward bias these junctions then diodes D1 and D2

should be added to protect the image sensor. Put one diode D1 between the ESD and VSUB pins. Put one diode D2 on

each pin that may forward bias the base-emitter junction. The diodes will prevent large currents from flowing through

the image sensor. Note that external diodes D1 and D2 are optional and are only needed if it is possible to forward bias

any of the junctions.

Note that diodes D1 and D2 are added external to the KAI-4021.

H1SL

H2SL

H1BL

H2BL

OGL

H1SR

H2SR

H1BR

H2BR

ESD

VSUB

OGR

KAI-4021 Datasheet(PDF) 15 Page - ON Semiconductor