HEDM-55xx/560x & HEDS-55xx/56xx
Quick Assembly Two and Three Channel Optical Encoders
Data Sheet
ESD WARNING: NORMAL HANDLING PRECAUTIONS SHOULD BE TAKEN TO AVOID STATIC DISCHARGE.
Description
The HEDS-5500/5540, HEDS-5600/5640, HEDM-5500/5540
and HEDM-5600 are high performance, low cost, two
and three channel optical incremental encoders. These
encoders emphasize high reliability, high resolution, and
easy assembly.
Each encoder contains a lensed LED source, an integrated
circuit with detectors and output circuitry, and a codewheel
which rotates between the emitter and detector IC. The
outputs of the HEDS-5500/5600 and HEDM-5500/ 5600
are two square waves in quadrature. The HEDS-5540/5640
and HEDM-5540 also have a third channel index output in
addition to the two channel quadrature. This index output
is a 90 electrical degree, high true index pulse which is
generated once for each full rotation of the codewheel.
The HEDS series utilizes metal codewheels, while the
HEDM series utilizes a lm codewheel allowing for resolu-
tions to 1024 CPR.
These encoders may be quickly and easily mounted to a
motor. For larger diameter motors, the HEDM-5600, and
HEDS-5600/5640 feature external mounting ears.
The quadrature signals and the index pulse are accessed
through ve 0.025 inch square pins located on 0.1 inch
centers.
Standard resolutions between 96 and 1024 counts per
revolution are presently available. Consult local Avago
sales representatives for other resolutions.
Features
• Two channel quadrature output with optional index
pulse
• Quick and easy assembly
• No signal adjustment required
• External mounting ears available
• Low cost
• Resolutions up to 1024 counts per revolution
• Small size –40°C to 100°C operating temperature
• TTL compatible
• Single 5 V supply
Applications
The HEDS-5500, 5540, 5600, 5640, and the HEDM-5500,
5540,5600 provide motion detection at a low cost, making
them ideal for high volume applications. Typical applica-
tions include printers, plotters, tape drives, positioning
tables, and automatic handlers.
Note: Avago Technologies encoders are not recommend-
ed for use in safety critical applications. Eg. ABS braking
systems, power steering, life support systems and critical
care medical equipment. Please contact sales representa-
tive if more clarication is needed.
2
Package Dimensions
HEDS-5500/5540, HEDM-5500/5540
*Notes:
For the HEDS-5500 and HEDM-5500, Pin #2 is a No Connect.
For the HEDS-5540 and HEDM-5540, Pin #2 is CH. I, the index output.
HEDS-5600/5640, HEDM-5600, HEDM-5640
*Notes:
For the HEDS-5600 and HEDM-5600, Pin #2 is a No Connect.
For the HEDS-5640 and HEDM-5640, Pin #2 is CH. I, the index output.
3
Theory of Operation
The HEDS-5500/5540, HEDS-5600/5640, HEDM-5500/5540
and HEDM-5600 translate the rotary motion of a shaft into
either a two- or a three-channel digital output.
As seen in the block diagram, these encoders contain a
single Light Emitting Diode (LED) as its light source. The
light is collimated into a parallel beam by means of a
single polycarbonate 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 rotates between the emitter and detector,
causing the light beam to be interrupted by the pattern
of spaces and bars on the codewheel. The photodi-
odes which detect these interruptions are arranged in a
pattern that corresponds to the radius and design of the
codewheel. 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 photo-
diode outputs are then fed through the signal processing
circuitry resulting in A, A, B and B (also I and I in the HEDS-
5540/5640 and HEDM-5540). Comparators receive these
signals and produce the nal 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).
In the HEDS-5540/5640 and HEDM-5540, the output of
the comparator for I and I is sent to the index processing
circuitry along with the outputs of channels A and B.
The nal output of channel I is an index pulse PO which
is generated once for each full rotation of the codewheel.
This output PO is a one state width (nominally 90 electri-
cal degrees), high true index pulse which is coincident
with the low states of channels A and B.
Block Diagram
Note: Circuitry for CH I is only for HEDS-5540/5640, HEDM-5540/5540 Three Channel Encoder
Denitions
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 (∆Θ): The normalized angular dierence
between the actual shaft position and the position
indicated by the encoder cycle count.
Cycle Error (∆C): An indication of cycle uniformity. The
dier¬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 neighbour-
ing transition in the output of channel B. There are 4 states
per cycle, each nominally 90°e.
State Width Error ( ∆S): The deviation, in electrical degrees, of
each state width from its ideal value of 90°e.
Phase (φ): 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 (∆φ): The deviation of the phase from its ideal
value of 90°e.
Direction of Rotation: When the codewheel rotates in the
counter-clockwise direction (as viewed from the encoder
end of the motor), channel A will lead channel B. If the
codewheel rotates in the clockwise direction, channel B
will lead channel A.
Index Pulse Width (PO): The number of electrical degrees that
an index output is high during one full shaft rotation. This
value is nominally 90°e or 1/4 cycle.
PHOTO
DIODES COMPARATORS
INDEX-
PROCESSING
CIRCUITRY
SIGNAL PROCESSING
CIRCUITRY
DETECTOR SECTION
CODE
WHEEL
EMITTER
SECTION
LENS
LED
VCC
CH. A
CH. B
CH. I
GND
RESISTOR
+
−
A
A
+
−
B
B
+
−
I
I
4
Absolute Maximum Ratings
Parameter HEDS-55XX/56XX HEDM-550X/560X HEDM-5540/5640
Storage Temperature, TS -40°C to 100°C -40°C to +70°C -40°C to 85°C
Operating Temperature, TA -40°C to 100°C -40°C to +70°C -40°C to 85°C
Supply Voltage, VCC -0.5 V to 7 V -0.5 V to 7 V -0.5 V to 7 V
Output Voltage, VO -0.5 V to VCC -0.5 V to VCC -0.5 V to VCC
Output Current per Channel, IOUT -1.0 mA to 5 mA -1.0 mA to 5 mA -1.0 mA to 5 mA
Vibration 20 g, 5 to 1000 Hz 20 g, 5 to 1000 Hz 20 g, 5 to 1000 Hz
Shaft Axial Play ± 0.25 mm
(± 0.010 in.)
± 0.175 mm
(± 0.007 in.)
± 0.175 mm
(± 0.007 in.)
Shaft Eccentricity Plus Radial Play 0.1 mm
(0.004 in.) TIR
0.04 mm
(0.0015 in.) TIR
0.04 mm
(0.0015 in.) TIR
Velocity 30,000 RPM 30,000 RPM 30,000 RPM
Acceleration 250,000 rad/sec2 250,000 rad/sec2 250,000 rad/sec2
Output Waveforms
P
C
CH. A
CH. B
ROTATION
AMPLITUDE
φ
S1 S2 S3 S4
CH. I
2.4 V
0.4 V
2.4 V
0.4 V
2.4 V
0.4 V
P0
t1t2
5
Recommended Operating Conditions
Parameter Sym. Min. Typ. Max. Units Notes
Temperature HEDS Series TA -40 100 °C
Temperature HEDM Series 5500/5600 TA -40 70 °C non-condensing
atmosphere
5540/5640 TA-40 85 °C
Supply Voltage VCC 4.5 5.0 5.5 Volts Ripple < 100 mVp-p
Load Capacitance CL 100 pF 2.7 kΩ pull-up
Count Frequency f 100 kHz Velocity (rpm) x N/60
Shaft Perpendicularity
Plus Axial Play (HEDS Series)
± 0.25
(±0.010)
mm
(in.)
6.9 mm (0.27 in.)
from mounting surface
Shaft Eccentricity Plus
Radial Play (HEDS Series)
0.04
(0.0015)
mm (in.)
TIR
6.9 mm (0.27 in.)
from mounting surface
Shaft Perpendicularity
Plus Axial Play (HEDM Series)
± 0.175
(±0.007)
mm
(in.)
6.9 mm (0.27 in.)
from mounting surface
Shaft Eccentricity Plus
Radial Play(HEDM Series)
0.04
(0.0015)
mm (in.)
TIR
6.9 mm (0.27 in.)
from mounting surface
Note: The module performance is guaranteed to 100 kHz but can operate at higher frequencies. 2.7 kΩ pull-up resistors required for HEDS-
5540/5640 and HEDM-5540/ 5640.
Encoding Characteristics
Part No. Description Sym. Min Typ.* Max. Units
HEDS-5500
HEDS-5600
(Two Channel)
Pulse Width Error
Logic State Width Error
Phase Error
Position Error
Cycle Error
∆P
∆S
∆Φ
∆Θ
∆C
7
5
2
10
3
45
45
20
40
5.5
°e
°e
°e
min. of arc
°e
HEDM-5500
HEDM-5600
(Two Channel)
Pulse Width Error
Logic State Width Error
Phase Error
Position Error
Cycle Error
∆P
∆S
∆Φ
∆Θ
∆C
10
10
2
10
3
45
45
15
40
7.5
°e
°e
°e
min. of arc
°e
HEDS-5540
HEDS-5640
(Three Channel)
Pulse Width Error
Logic State Width Error
Phase Error
Position Error
Cycle Error
Index Pulse Width
∆P
∆S
∆Φ
∆Θ
∆C
Po 55
5
5
2
10
3
90
45
35
15
40
5.5
125
°e
°e
°e
min. of arc
°e
°e
CH.I rise after
CH.A or CH. B fall
-40°C to +100°C t1-300 100 250 ns
CH.I fall after
CH.A or CH. B rise
-40°C to +100°C t270 150 1000 ns
HEDM-5540
HEDM-5640
(Three Channel)
Pulse Width Error
Logic State Width Error
Phase Error
Position Error
Cycle Error
Index Pulse Width
∆P
∆S
∆Φ
∆Θ
∆C
Po 50
10
10
2
10
6
90
45
45
15
40
12
130
°e
°e
°e
min. of arc
°e
°e
CH.I rise after
CH.A or CH. B fall
-40°C to + 85°C t1200 1000 1500 ns
CH.I fall after
CH.A or CH. B rise
-40°C to + 85°C t20 300 1500 ns
Note: See Mechanical Characteristics for mounting tolerances. *Typical values specied at VCC = 5.0 V and 25°C.
6
Electrical Characteristics
Electrical Characteristic over Recommended Operating Range
Part No. Parameter Sym. Min Typ.* Max. Units Notes
HEDS-5500
HEDS-5600
Supply Current
High Level Output Voltage
Low Level Output Voltage
ICC
VOH
VOL
2.4
17 40
0.4
mA
V
V
IOH = -40μA max
IOL= 3.2mA
Rise Time
Fall Time
tr
tf
200
50
ns
ns
CL= 25 pF
RL = 11 kΩ pull-up
HEDS-5540
HEDS-5640
HEDM-5500
HEDM-5600
Supply Current
High Level Output Voltage
Low Level Output Voltage
ICC
VOH
VOL
30
2.4
57 85
0.4
mA
V
V
IOH = -200μA max
IOL= 3.86mA
Rise Time
Fall Time
tr
tf
180
40
ns
ns
CL= 25 pF
RL = 2.7 kΩ pull-up
HEDM-5500
HEDM-5600
Supply Current
High Level Output Voltage
Low Level Output Voltage
ICC
VOH
VOL
30
2.4
57 85
0.4
mA
V
V
IOH = -40μA max
IOL= 3.86mA
Rise Time
Fall Time
tr
tf
180
40
ns
ns
CL= 25 pF
RL = 3.2 kΩ pull-up
HEDM-5540
HEDM-5640
Supply Current
High Level Output Voltage
Low Level Output Voltage
ICC
VOH
VOL
30
2.4
57 85
0.4
mA
V
V
IOH = -200μA max
IOL= 3.86mA
Rise Time
Fall Time
tr
tf
200
80
ns
ns
CL= 25 pF
RL = 2.7 kΩ pull-up
* Typical values specied at VCC = 5.0V and 25ºC
7
Electrical Interface
To insure reliable encodingperformance, the HEDS-5540/5640 and HEDM-5540 three channel encoders require 2.7 kΩ (±
10%) pull-up resistors on output pins 2, 3, and 5 (Channels I, A, and B) as shown in Figure 1. These pull-up resistors should
be located as close to the encoder as possible (within 4 feet). Each of the three encoder outputs can drive a single TTL
load in this conguration. The HEDS-5500, 5600, and HEDM-5500, 5600 two channel encoders do not normally require
pull-up resistors. However, 3.2 kΩ pull-up resistors on output pins 3 and 5 (Channels A and B) are recommended to
improve rise times, especially when operating above 100 kHz frequencies.
Figure 1. Pull-up Resistors on HEDS-5x40 and HEDM-5540 Encoder Outputs.
Mechanical Characteristics
Parameter Symbol Dimension Tolerance[1] Units
Codewheel Fits These Standard
Shaft Diameters
2 3 4
5 6 8
+0.000
-0.015
mm
5/32 1/8
3/16 1/4
+0.0000
-0.0007
in
Moment of Inertia J 0.6 (8.0 x 10-6) g-cm2 (oz-in-s2)
Required Shaft Length [2] 14.0 (0.55) ± 0.5
(± 0.02)
mm (in.)
Bolt Circle [3] 2 screw mounting 19.05
(0.750)
± 0.13
(± 0.005)
mm (in.)
3 screw mounting 20.90
(0.823)
± 0.13
(± 0.005)
mm (in.)
external mounting ears 46.0
(1.811)
± 0.13
(± 0.005)
mm (in.)
Mounting Screw Size [4] 2 screw mounting M 2.5 or (2-56) mm (in.)
3 screw mounting M 1.6 or (0-80) mm (in.)
external mounting ears M 2.5 or (2-56) mm (in.)
Encoder Base Plate Thickness 0.33 (0.130) mm (in.)
Hub Set Screw (2-56) (in.)
Notes:
1. These are tolerances required of the user.
2. The HEDS-55x5 and 56x5, HEDM-5505, 5605 provide an 8.9 mm (0.35 inch) diameter hole through the housing for longer motor shafts. See
Ordering Information.
3. The HEDS-5540 and 5640 must be aligned using the aligning pins as specied in Figure 3, or using the alignment tool as shown in “Encoder
Mounting and Assembly”. See also “Mounting Considerations.”
4. The recommended mounting screw torque for 2 screw and external ear mounting is 1.0 kg-cm (0.88 in-lbs). The recommended mounting screw
torque for 3 screw mounting is 0.50 kg-cm (0.43 in-lbs).
8
Figure 2. Mounting Holes. Figure 3. Optional Mounting Aids.
Figure 4. Mounting with External Ears.
Mounting Considerations
The HEDS-5540 and 5640 three channel encoders and the HEDM Series high resolution encoders must be aligned using
the aligning pins as specied in Figure 3, or using the HEDS-8910 Alignment Tool as shown in Encoder Mounting and
Assembly.
The use of aligning pins or alignment tool is recommended but not required to mount the HEDS-5500 and 5600. If these
two channel encoders are attached to a motor with the screw sizes and mounting tolerances specied in the mechanical
characteristics section without any additional mounting bosses, the encoder output errors will be within the maximums
specied in the encoding characteristics section. The HEDS-5500 and 5540 can be mounted to a motor using either the
two screw or three screw mounting option as shown in Figure 2. The optional aligning pins shown in Figure 3 can be
used with either mounting option. The HEDS-5600, 5640, and HEDM-5600 have external mounting ears which may be
used for mounting to larger motor base plates. Figure 4 shows the necessary mounting holes with optional aligning pins
and motor boss.
9
Encoder Mounting and Assembly
1a. For HEDS-5500 and 5600: Mount encoder base plate onto motor. Tighten screws. Go on to step 2.
1b. For HEDS-5540, 5640 and HEDM-5500, 5600, 5540 : Slip alignment tool onto motor shaft. With alignment tool in
place, mount encoder baseplate onto motor as shown above. Tighten screws. Remove alignment tool.
1c. It is recommended that adhesive* is applied to the screw-baseplate interface to prevent screw loosening due to
eect of high temperature on plastic
2. Snap encoder body onto base plate locking all 4 snaps.
3a. Push the hex wrench into the body of the encoder to ensure that it is properly seated into the code wheel hub set
screws. Then apply a downward force on the end of the hex wrench. This sets the code wheel gap by levering the
code wheel hub to its upper position.
3b. While continuing to apply a downward force, rotate the hex wrench in the clockwise direction until the hub set
screw is tight against the motor shaft (The recommended torque to tighten the setscrew is 15-18 ozf.inch). The hub
set screw attaches the code wheel to the motor’s shaft.
3c. Remove the hex wrench by pulling it straight out of the encoder body.
4. Use the center screwdriver slot, or either of the two side slots, to rotate the encoder cap dot clockwise from the one
dot position to the two dot position. Do not rotate the encoder cap counterclockwise beyond the one dot position.
The encoder is ready for use!
10
Connectors
Manufacturer Part Number
AMP 103686-4
640442-5
Avago (designed to mechanically lock into the
HEDS-5XXX, HEDM-5X0X Series)
HEDS-8902 (2 ch.) with 4-wire leads
HEDS-8903 (3 ch.) with 5-wire leads
Molex 2695 series with 2759 series term.
Single ended cable connector P/N : 0050579405 and P/N : 0016020097.
Figure 5. HEDS-8902 nd 8903 connectors
Protective Silicon Cover
Protective Silicon Rubber cover gives an extra protection
for HEDS-5xx0 and HEDM-5xx0 family when operating in
dusty environment.
The protective silicon cover is installed to HEDS-5xx0
or HEDM-5xx0 prior to the connector to the encoder is
installed.
Part Number HEDS-8907-001
Material
Silicon Rubber- Semi transparent-ESD
protective material
Used With HEDS-5xx0 and HEDM-5xx0
Temperature Range -40ºC to 100ºC
42.50
1.673
31.40
1.236
14.00
.551
16.50
.650
7.20
.283
1. Dimensions are in
2. All tolerances are within ±0.5
millimeters
Inches
11
Shaft Diameter
01 - 2 mm 06 - 1/4 in.
02 - 3 mm 11 - 4 mm
03 - 1/8 in. 14 - 5 mm
04 - 5/32 in. 12 - 6 mm
05 - 3/16 in. 13 - 8 mm
Mounting Type
5 - Standard
6 - External
Mounting Ears
Resolution (Cycles/Rev)
B - 1000 CPR
J - 1024 CPR
M - 800 CPR
Through Hole
0 - None
5 - 8.9 mm (0.35 in.)
Outputs
0 - 2 Channel
4 - 3 Channel
8 - 2 Channel (Latch)
9 - 3 Channel (Latch)
HEDS-8910 0 Alignment Tool
HEDM-5 0 Option
HEDS-5 Option
Shaft Diameter
01 - 2 mm 06 - 1/4 in.
02 - 3 mm 11 - 4 mm
03 - 1/8 in. 14 - 5 mm
04 - 5/32 in. 12 - 6 mm
05 - 3/16 in. 13 - 8 mm
Mounting Type
5 - Standard
6 - External
Mounting Ears
Through Hole
0 - None
5 - 8.9 mm (0.35 in.)
Outputs
0 - 2 Channel
4 - 3 Channel
8 - 2 Channel (Latch)
9 - 3 Channel (Latch)
HEDS-8910 0 Alignment Tool
Resolution (Cycles/Rev)
(HEDS-550X, 560X 2 Channel)
S - 50 CPR F - 256 CPR
K - 96 CP G - 360 CPR
C - 100 CPR H - 400 CPR
D - 192 CPR A - 500 CPR
E - 200 CPR I - 512 CPR
(HEDS-554X, 564X 3 Channel)
S - 50 CPR
K - 96 CPR
C - 100 CPR
E - 200 CPR
F - 256 CPR
G - 360 CPR
H - 400 CPR
A - 500 CPR
I - 512 CPR
Typical Interfaces
HOST
PROCESSOR
HEDS–55XX
OR
HEDS-56XX
OR
HEDM-5X0X
HCTL-20xx
QUADRATURE
DECODER/
COUNTER
CH. A
CH. B
HOST
PROCESSOR
CH. B
CH. A
HEDS–55XX
OR
HEDS-56XX
OR
HEDM-5X0X
HCTL-1100
MOTION
CONTROL IC
Ordering Information
Encoders with Film Codewheels
(Included with each order of HEDM-550X/560X two channel encoders and HEDM-554X three Channel encoders)
(Included with each order of HEDS-554X/564X three channel encoders)
01 02 03 04 05 06 11 12 13 14
HEDM-5500 B * * * * * * *
J * * * * *
HEDM-5505 B *
J * * *
HEDM-5540 B * * * * * *
HEDM-5540 M * *
HEDM-5545 B *
HEDM-5600 B * *
J *
HEDM-5605 B *
J *
HEDM-5640 M * *
HEDS-5500 A * * * * * * * * * *
C * * * * * * * * * *
E * * * * * * *
F * * * * * * * *
G * * * * *
H * * * *
I * * * * * * * * * *
K * * * *
S *
HEDS-5505 A * * * *
C * * * *
E * * *
F * * *
G * *
H * *
I * * *
K *
HEDS-5540 A * * * * * * * * * *
C * * * * * * *
E * * *
F * * *
G *
H * *
I * * * * * * *
01 02 03 04 05 06 11 12 13 14
HEDS-5545 A * *
C *
H * *
I *
HEDS-5600 A * * * *
C * * *
E *
G * *
H * *
I * *
HEDS-5605 A * *
C *
E *
F *
G *
H * *
I *
HEDS-5640 A * * *
E *
F *
H *
HEDS-5645 A * * *
C *
E *
G *
H * * *
I *
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 © 2005-2014 Avago Technologies. All rights reserved.
AV02-1046EN - November 20, 2014
Mouser Electronics
Authorized Distributor
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HEDM-5500#B13 HEDS-5500#A02 HEDS-5500#A03 HEDS-5500#A13 HEDS-5500#F06 HEDS-5500#G05
HEDS-5500#I06 HEDS-5500#K05 HEDS-5540#A02 HEDS-5540#A05 HEDS-5540#H14 HEDS-5645#A06 HEDM-
5540-B05 HEDM-5540-B02 HEDS-8910#002 HEDS-8910#004 HEDS-8910#005 HEDS-8910#006 HEDS-8910#011
HEDS-8910#012 HEDS-8910#013 HEDS-8910#014 HEDS-8907-001