HEDB-9100 and HEDB-9000
Two Channel Optical Incremental Encoder
Modules Bundle With Codewheel
Data Sheet
Description
The HEDB-9100 and HEDB-9000 series are two channel
optical incremental encoder modules offered with a
codewheel. When used with a codewheel, these low cost
modules detect rotary position. Each module consists of
a lensed LED source and a detector IC enclosed in a small
C-shaped plastic package. Due to a highly collimated light
source and a unique photodetector array, these modules
are extremely tolerant to mounting misalignment.
The HEDB-9100 and 9000 has two channel quadrature
outputs.
The HEDB-9100 is designed for use with a HEDS-5120
codewheel which has an optical radius of 11.00 mm
(0.433 inch).The HEDB-9000 is designed for use with a
HEDS-6100 codewheel which has an optical radius of
23.36 mm (0.920 inch).
The quadrature signals and the single 5V supply input are
accessed through five 0.025 inch square pins located on
0.1 inch (pitch) centers.
Features
High Performance
Resolution from 96 CPR Up To 1000 CPR (Counts Per
Revolution)
Low Cost
Easy to Mount
No Signal Adjustment required
Small Size
Operating Temperature: -40°C to 100°C
TTL Compatible
Two Channel Quadrature Output
Single 5V Supply
Applications
The HEDB-9100 and 9000 provide sophisticated motion
control detection at a low cost, making them ideal for high
volume applications. Typical applications include printers,
plotters, tape drives, and industrial and factory automa-
tion 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 HEDB-9100 and 9000 is emitter/detector modules.
Coupled with a codewheel, these modules translate
the rotary motion of a shaft into a two-channel digital
output.
As seen in Figure 1, the modules contain a single Light
Emitting Diode (LED) as its light source. The light is col-
limated into a parallel beam by means of a single poly-
carbonate 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 process-
ing circuitry necessary to produce the digital waveforms.
The codewheel rotates between the emitter and detector,
causing the light beam to be interrupted by the pattern of
spaces and bars on the codewheel.
The photodiodes which detect these interruptions are
arranged in a pattern that corresponds to the radius and
design of the code-wheel. These detectors are also spaced
such that a light period on one pair of detectors corre-
sponds to a dark period on the adjacent pair of detectors.
The photodiode outputs are then fed through the signal
processing circuitry resulting in A, Abar, B, Bbar. Two com-
parators 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 that of channel B (90 degrees out of phase).
Cycle Error (C):
An indication of cycle uniformity. The differ-
ence between an observed shaft angle which gives rise to
one electrical cycle, and the nominal angular increment of
1/N of a revolution.
Pulse Width (P):
The number of electrical degrees that an
output is high during 1 cycle. This value is nominally 180°e
or 1/2 cycle.
Pulse Width Error (P):
The deviation, in electrical degrees, of
the pulse width from its ideal value of 180°e.
State Width (S):
The number of electrical degrees between a
transition in the output of channel A and the neighboring
transition in the output of channel B. There are 4 states per
cycle, each nominally 90°e.
Phase ():
The number of electrical degrees between the
center of the high state of channel A and the center of the
high state of channel B. This value is nominally 90°e for
quadrature output.
Phase Error ():
The deviation of the phase from its ideal
value of 90°e.
Direction of Rotation:
When the codewheel rotates in the
clockwise direction viewing from top of the module
(direction from V to G), channel A will lead channel B. If
the codewheel rotates in the opposite direction, channel
B will lead channel A.
Optical Radius (Rop):
The distance from the codewheel’s
center of rotation to the optical center (O.C) of the encoder
module.
Definitions
Note: Refer to Figure 2
Count (N):
The number of bar and window pairs or counts
per revolution (CPR) of the codewheel.
One Cycle (C):
360 electrical degrees (°e), 1 bar and window
pair.
One Shaft Rotation:
360 mechanical degrees, N cycles.
Position Error ():
The normalized angular difference
between the actual shaft position and the position
indicated by the encoder cycle count.
Specification
For encoder electrical, mechanical specifications,
codewheel technical specifications and additional infor-
mations pls refer to :
HEDS-9000 /9100 Datasheet.
HEDS/HEDG/HEDM – 51xx/61xx Codewheel Datasheet
2
Block Diagram
RESISTOR
LENS
PHOTO-
DIODES
LED
COMPARATORS
A
+
A
-
B
+
V
CC
3
CHANNEL A
2
CHANNEL B
4
B
-
SIGNAL
PROCESSING
CIRCUITRY
GND
1
EMITTER
SECTION
Figure 1. Block Diagram
CODE
WHEEL
DETECTOR SECTION
Output Waveforms
P
C
CHANNEL A
AMPLITUDE
ф
S1
S2
S3
S4
CHANNEL B
ROTATION
Figure 2. Output waveforms
3
Ordering Information
Three Channel Encoder Modules with Codewheel, 11 mm and 23.36 Optical Radius
HEDB - 9
00 -
Codewheel Rop
0 - 23.36 mm
1 - 11.00 mm
Resolutions
(Cycle/Rev)
K - 96 CPR
C - 100 CPR
E - 200 CPR
F - 256 CPR
G - 360 CPR
H - 400 CPR
A - 500 CPR
I - 512 CPR
B - 1000 CPR
J - 1024 CPR
Shaft Diameter
01 - 2mm
02 - 3mm
03 - 1/8 in
04 - 5/32 in
05 - 3/16 in
06 - 1/4 in
08 - 3/8 in
09 - 1/2 in
10 - 5/8 in
11 - 4mm
12 - 6mm
13 - 8mm
14 - 5mm
Available Options
Shaft Diameter Options
Part Number
HEDB-9100
CPR
K
C
E
G
H
A
I
01
02
03
04
05
06
08
09
10
11
12
13
14
Shaft Diameter Options
Part Number
HEDB-9000
CPR
A
B
01
02
03
04
05
06
08
09
10
11
12
13
14
4
Bundle Part Number Breakdown List
HEDB - 9100 - CPR
Shaft Diameter
00
Encoder Module : HEDS-9100 - CPR
Codewheel : HEDS - 5120 - CPR
Shaft Diameter
HEDB - 9000 - CPR
Shaft Diameter
00
Encoder Module : HEDS-9000 - CPR
Codewheel : HEDS - 6100 - CPR
Shaft Diameter
Note : The bundle part HEDB-9100/9000 consists of HEDS-9100/9000 and HEDS-5120/6100. The diagram below provides the breakdown list.
For product information and a complete list of distributors, please go to our web site:
www.avagotech.com
Avago, Avago Technologies, and the A logo are trademarks of Avago Technologies in the United States and other countries.
Data subject to change. Copyright © 2005-2012 Avago Technologies. All rights reserved. Obsoletes 5989-4045EN
AV02-3608EN - June 12, 2012
