Holtek AN0315E, Using Manual

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Using the HT45FH3T in the Active 3D Glasses
1
Using the HT45FH3T for Active 3D Glasses
D/N: A
N
0315E
Introduction
With the continuous development of people’s living standards, the requirements for
audio-visual entertainment is increasing, thus more and more 3D videos, movies and
games are being produced and along with this is the rising demand for 3D glasses. A new
3D technology, a combination of active shutter 3D technology and active shutter 3D glasses,
is widely used in TV and projector applications and provides good imaging effects.
The Holtek HT45FH3T is especially designed for active 3D glasses development and this
application sets out to show how it is used in such applications.
3D Glasses Functions
The main function of 3D glasses is to receive and decode the IR signals from the TV for
3D glasses control. Due to the high voltage driving requirement, a boost circuit is needed
to increase the battery voltage to 10V~12V for 3D glasses driving. A pair of 3D glasses
contains two lenses each for the left eye and right eye. As each lens needs two high
driving voltages, thus four high driving voltages are needed. So each 3D glasses circuit
contains four level shift circuits, which are used to increase the 3V MCU I/O output
voltage to 10V~12V for the 3D glasses on/off control. In addition, each pair of 3D glasses
needs an IR receiver circuit to receive external IR signals.
3D glasses normally use a battery power supply, which can be divided into two types. The
first type is a chargeable lithium battery and the second type is a non-chargeable button
battery. An additional lithium battery charging circuit is required when using the lithium
battery.