HEDS-973x Series
Small Optical Encoder Modules
Data Sheet
Description Features
Small size
The HEDS-973x series is a high performance, low cost,
optical incremental encoder module. When operated in
Low cost
conjunction with either a codewheel or codestrip, this
Multiple mounting options
module detects rotary or linear position. The module
Wide resolution range
consists of a lensed LED source and a detector IC enclosed
Linear and rotary options available
in a small C-shaped plastic package. Due to a highly
No signal adjustment required
collimated light source and a unique photodetector array,
Insensitive to radial and axial play
the module is extremely tolerant to mounting
misalignment.
C to +85C operating temperature
- 40
High resolution version of the HEDS-970x
Two channel quadrature output
TTL compatible
Single 5 V supply
Wave solderable
Package Dimensions
Mounting Option #50 - Standard (Baseplane Mounting) Contact Factory for Detailed Package Dimensions
ESD WARNING: NORMAL HANDLING PRECAUTIONS SHOULD BE TAKEN TO AVOID STATIC DISCHARGE.The two channel digital outputs Theory of Operation The codewheel/codestrip moves
and 5 V supply input are accessed between the emitter and detector,
The HEDS-973X is a C-shaped
through four solder-plated leads causing the light beam to be inter-
emitter/detector module. Coupled
located on 2.54 mm (0.1 inch) rupted by the pattern of spaces
with a codewheel, it translates
centers. and bars on the codewheel/code-
rotary motion into a two-channel
strip. The photodiodes which
digital output. Coupled with a
The standard HEDS-973x is detect these interruptions are
codestrip, it translates linear
designed for use with an 11 mm arranged in a pattern that corre-
motion into a digital output.
optical radius codewheel, or sponds to the radius and count
linear codestrip. Other options density of the codewheel/code-
As seen in the block diagram, the
are available. Please contact strip. These detectors are also
module contains a single Light
factory for more information. spaced such that a light period on
Emitting Diode (LED) as its light
one pair of detectors corresponds
source. The light is collimated
Applications to a dark period on the adjacent
into a parallel beam by means of
pair of detectors. The photodiode
The HEDS-973x provides a single lens located directly over
outputs are fed through the signal
sophisticated motion detection at the LED. Opposite the emitter is
processing circuitry. Two com-
a low cost, making closed-loop the integrated detector circuit.
parators receive these signals and
control very cost-competitive! This IC consists of multiple sets
produce the final outputs for
Typical applications include of photodetectors and the signal
channels A and B. Due to this
printers, plotters, copiers, and processing circuitry necessary to
integrated phasing technique, the
office automation equipment. produce the digital waveforms.
digital output of channel A is in
.
quadrature with channel B (90
Note: Avago Technologies
degrees out of phase).
encoders are not recommended
for use in safety critical
applications. Eg. ABS braking
systems, power steering, life
support systems and critical care
Block Diagram
medical equipment. Please
contact sales representative if
more clarification is needed.
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