Symbol SE 2223, Integration Manual

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1-3
Getting Started
Analog Front End
This transforms the signal current from the photodiode into a voltage signal, then filters and
amplifies for use by a digitizer. That signal is amplified, while noise and the effects of
ambient light are removed.
Digitizer
This analyzes the conditioned analog signal and threshold amplitudes to create a digitized
representation of the bar code being read.
Visible Laser Diode (VLD) Driver
This consists mainly of an operational amplifier, which regulates optical power from the
laser.
Single Chip Decoding System (SCDS)
This controls operating frequencies and amplitudes of both the X (horizontal) and Y
(vertical) patterns and contains the decoding algorithms.
The SCDS provides two functions:
• The motor control sections generate the waveform frequencies and shape to
control highly efficient scan elements.
• The decoder section has logic that converts the digital bar pattern (DBP) into an
SSI-compatible format that is sent serially to the host system.