Book 3

Zhaga Book 3 defines LED light engines (LLEs) that comprise a circular, non-socketable LED module with a separate LED driver (electronic control gear).

The circular LED modules in Book 3 have a typical diameter of 50 mm and a maximum height of 7.2 mm.

There are four LLE categories in Book 3, which are defined by the maximum diameter of the circular light-emitting surface (LES). 

Book 3 LLEs are suitable for spot-lighting and other applications that benefit from a small, circular source.

Publication status

Public downloads are available:

Download Book 3 (English) - Edition 1.3, January 2014

Download Book 3 (Chinese) - Edition 1.2, October 2012

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Specification details

This Book must be read together with Zhaga Book 1.

LED module dimensions



diameter (mm)

Screw-hole separation

distance (mm)


height (mm)

Book 11 35 25 3.5
Book 3 50 35 7.2
Book 10 75   8.0

Light-emitting surface (LES) categories

LES category

Minimum LES

diameter (mm)

Maximum LES

diameter (mm)

LES 9 > 6.3 9.0
LES 13.5 > 9.0 13.5
LES 19 > 13.5 19.0
LES 23 > 19 23


Book 3 photos

Book 3 demo with MechaTronix heatsinks, different COBs and holders, and Almeco reflector (left).