September 2011

Doc ID 019041 Rev 1

1/24

AN3432

Application note

How to choose a bypass diode for a silicon panel junction box

Introduction

Today, the main technologies used in solar panel are polycrystalline and mono crystalline

silicon solar cells. When one solar cell of the panel is shaded while the others are

illuminated, a hot spot could appear and leads to the shaded cell destruction. The bypass

diode is an efficient solution to eliminate the “hot spot” and maintain the current delivery. The

and junction box characteristics.

This document gives a method to select the most appropriate diode versus the panel

characteristics.

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