HEDS-9731#253 Avago Technologies US Inc., HEDS-9731#253 Datasheet - Page 2
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HEDS-9731#253
Manufacturer Part Number
HEDS-9731#253
Description
Encoders 2 Channel 300CPR
Manufacturer
Avago Technologies US Inc.
Datasheet
1.HEDS-9731253.pdf
(11 pages)
Specifications of HEDS-9731#253
Number Of Channels
2
Mounting Style
PCB
Supply Voltage
5 V
Product
Optical
Technology
Linear
Termination Style
Solder Pin
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
The two channel digital outputs and 5 V supply input are
accessed through four solder-plated leads located on .54
mm (0.1 inch) centers.
The standard HEDS-973x is designed for use with an 11
mm optical radius codewheel, or linear codestrip. Other
options are available. Please contact factory for more in-
formation.
Applications
The HEDS-973x provides sophisticated motion detection
at a low cost, making closed-loop control very cost-com-
petitive! Typical applications include printers, plotters,
copiers, and office automation equipment.
Note: Avago Technologies encoders are not recommended for use in
safety critical applications. Eg. ABS braking systems, power steering, life
support systems and critical care medical equipment. Please contact
sales representative if more clarification is needed.
Theory of Operation
The HEDS-973X is a C-shaped emitter/detector module.
Coupled with a codewheel, it translates rotary motion into
a two-channel digital output. Coupled with a codestrip, it
translates linear motion into a digital output.
As seen in the block diagram, the module contains a single
Light Emitting Diode (LED) as its light source. The light is
collimated into a parallel beam by means of a single lens
located directly over the LED. Opposite the emitter is the
integrated detector circuit. This IC consists of multiple
sets of photodetectors and the signal processing circuitry
necessary to produce the digital waveforms.
The codewheel/codestrip moves between the emitter and
detector, causing the light beam to be interrupted by the
pattern of spaces and bars on the codewheel/codestrip.
The photodiodes which detect these interruptions are
arranged in a pattern that corresponds to the radius and
count density of the codewheel/codestrip. These detectors
are also spaced such that a light period on one pair of
detectors corresponds to a dark period on the adjacent
pair of detectors. The photodiode outputs are fed through
the signal processing circuitry. Two comparators receive
these signals and produce the final outputs for channels
A and B. Due to this integrated phasing technique, the
digital output of channel A is in quadrature with channel
B (90 degrees out of phase).
Block Diagram