HEDR-5120#E06 Avago Technologies US Inc., HEDR-5120#E06 Datasheet - Page 2

• Manufacturer Part Number: HEDR-5120#E06
• Description: Ref CW,28mm,2Ch,200CPR,1/4in
• Manufacturer: Avago Technologies US Inc.

Specifications of HEDR-5120#E06

• Pulses Per Revolution: 200 CPR
• Number Of Channels: 2
• Product: Optical
• Size / Dimension: 1/4 in
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The reflective surface mount optical encoders provide
two square wave outputs in quadrature for count and
direction information. These TTL compatible outputs
correspond to the alternating reflective/non-reflective
pattern of the codewheel or codestrip.
The HEDR-8000/8100 series encoders can be used over
a range of codewheel and codestrip resolutions. The
HEDR-8000/8100 reflective encoder can operate from
2.76 to 2.95 lines per mm (70 to 75 lines per inch). The
HEDR-8100 can be used with a codewheel or codestrip
with 150 lines per inch (5.91 lines per mm).
Applications
The HEDR-8000/8100 series provides two channel mo-
tion sensing at a very low cost, making it ideal for high
volume applications. Its small size and surface mount
capability make it ideal for printers, copiers, card read-
ers, and consumer product applications.
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.
Block Diagram
V
CH A
CH B
GND
GND
2
V
LED
CC
PROCESSING
CIRCUITRY
SIGNAL
R
HEDR-8000 block diag
Theory of Operation
The HEDR-8000/8100 series combines an emitter and a
detector in a single surface mount SO-8 package. When
used with a codewheel or codestrip, the reflective sen-
sors translates rotary or linear motion into a two chan-
nel digital output.
As seen in the block diagram, the HEDR-8000/8100
series has three key parts: a single light emitting diode
(LED) light source, a photodetector IC with a set of
uniquely configured photodiodes, and a pair of lenses
molded into the package. The lens over the LED focuses
light onto the codewheel or codestrip. Light is either
reflected or not reflected back to the lens over the pho-
todetector IC.
As the codewheel rotates or codestrip passes by, an
alternating pattern of light and dark corresponding to
the pattern of the codewheel falls upon the photodi-
odes. This light is used to produce internal signals A
and A, and B and B. As part of this “push-pull” detector
system, these signals are fed through comparators to
produce the final outputs for channels A and B.
CODEWHEEL
OR
CODESTRIP