ETC HEDS-9701C54

Small Optical Encoder Modules
Technical Data
HEDS-9700 Series
Features
• Small Size
• Low Cost
• Multiple Mounting Options
• Wide Resolution Range
• Linear and Rotary Options
Available
• No Signal Adjustment
Required
• Insensitive to Radial and
Axial Play
• -40°C to +85°C Operating
Temperature
• Two Channel Quadrature
Output
• TTL Compatible
• Single 5V Supply
• Wave Solderable
Description
The HEDS-9700 series is a high
performance, low cost, optical
incremental encoder module.
When operated in conjunction
with either a codewheel or
codestrip, this module detects
rotary or linear position. The
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.
2
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, the module is
extremely tolerant to mounting
misalignment.
The two channel digital outputs
and 5V supply input are accessed
through four solder-plated leads
located on 2.54 mm (0.1 inch)
centers.
The standard HEDS-9700 is
designed for use with an 11 mm
optical radius codewheel, or
linear codestrip. Other options
are available. Please contact
factory for more information.
Applications
The HEDS-9700 provides
sophisticated motion detection at
a low cost, making closed-loop
control very cost-competitive!
Block Diagram
Typical applications include
printers, plotters, copiers, and
office automation equipment.
Theory of Operation
The HEDS-9700 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).
3
Output Waveforms
A and the neighboring 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.
Definitions
Count (N) = The number of bar
and window pairs or counts per
revolution (CPR) of the
codewheel, or the number of lines
per inch of the codestrip (LPI).
Pulse Width (P): The number of
electrical degrees that an output
is high during one cycle. This
value is nominally 180°e or 1/2
cycle.
1 Shaft Rotation = 360
mechanical
degrees
= N cycles
1 cycle (c) = 360 electrical
degrees (°e)
= 1 bar and
window pair
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
Absolute Maximum Ratings
Parameter
Symbol
Min. Max. Units
Notes
Storage Temperature
TS
-40
85
°C
See Note
Operating
Temperature
TA
-40
85
°C
See Note
Supply Voltage
VCC
-0.5
7
V
Output Voltage
VO
-0.5
VCC
V
Output Current per
Channel
IO
-1.0
5
mA
260
°C
Soldering Temperature
t ≤ 5 sec.
Phase Error (∆φ): The deviation
of the phase from its ideal value
of 90°e.
Direction of Rotation: When the
codewheel rotates counterclockwise, as viewed looking down on
the module (so the marking is
visible), 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.
4
Recommended Operating Conditions
Parameter
Symbol
Min.
Max.
Units
Τ
−40
85
°C
Supply Voltage
VCC
4.5
5.5
V
Load Capacitance
CL
100
pF
3.2 kΩ pull-up
20
kHz
(Velocity (rpm) x N)/60
Temperature
Count Frequency
Notes
Ripple < 100 mVp-p
Note: The module performance is guaranteed to 20 kHz but can operate at higher frequencies. Contact factory for more information.
Encoding Characteristics
Encoding Characteristics over Recommended Operating Range and Recommended Mounting Tolerances.
These characteristics do not include codewheel/codestrip contributions.
Symbol
Typ.
Case 1
Max.
Case 2
Max.
Units
Pulse Width Error
∆P
7
30
40
°e
Logic State Width Error
∆S
5
30
40
°e
Phase Error
∆φ
2
10
15
°e
Parameter
Notes
Case 1: Module mounted on tolerances of ± 0.13 mm (0.005"). Case 2: Module mounted on tolerances of
± 0.25 mm (0.010")
Note: See Figures in Mounting Considerations for details on Case 1 and Case 2 mounting tolerances.
Electrical Characteristics
Electrical Characteristics over Recommended Operating Range, Typical at 25°C.
Parameter
Symbol
Supply Current
ICC
High Level Output Voltage
VOH
Low Level Output Voltage
VOL
Min.
Typ.
Max.
Units
17
40
mA
2.4
0.4
Notes
V
IOH = -40 µA
V
IOL = 3.2 mA
Rise Time
tr
200
ns
CL = 25 pF, RL = 11 kΩ
Fall Time
tf
50
ns
CL = 25 pF, RL = 11 kΩ
5
Recommended Codewheel and Codestrip Characteristics
Parameter
Symbol
Min.
Max.
Window/Bar Ratio
Ww/Wb
0.7
1.4
Window Length (Rotary)
Lw
1.80
(0.071)
2.30
(0.091)
mm
(inch)
Absolute Maximum Codewheel
Radius (Rotary)
Rc
Rop + 3.40
(Rop + 0.134)
mm
(inch)
Center of Post to Inside
Edge of Window
W1
1.04
(0.041)
mm
(inch)
Center of Post to Outside
Edge of Window
W2
0.76
(0.030)
mm
(inch)
Center of Post to Inside Edge
of Codestrip
L
Optional Packages Available
Mounting Option #51 – Rounded Outline (Baseplane Mounting)
3.60
(0.142)
Units
mm
(inch)
Notes
Includes eccen–
tricity errors
6
Optional Packages Available (cont'd.)
Mounting Option #52 – Backplane (Backplane Mounting)
Mounting Option #53 – Standard with Posts (Baseplane Mounting)
7
Optional Packages Available (cont'd.)
Mounting Option #54 – Tabless (Baseplane Mounting)
Mounting Option #55 – Backplane with Posts (Backplane Mounting)
8
Bent Lead Option
Mounting Considerations
Note: These dimensions include shaft end play and codewheel warp.
All dimensions for mounting the module and codewheel/codestrip should be measured with respect to the two mounting posts, shown
above.
Mounting Tolerances
Case 1 and Case 2 specify the mounting tolerances required on Rm in order to achieve the respective
encoding characteristics shown on page 4. The mounting tolerances are as follows:
Case 1: Rm ± 0.13 mm (.005 inches)
Case 2: Rm ± 0.25 mm (.010 inches)
Recommended Screw Size: M2.5 x 0.45 or 2-56
9
Wave Solder Conditions
Flux – RMA Water Soluble (per
MIL-F-14256D)
Process Parameters
1. Flux
2. Pre-heat 60 seconds total
PCB top side @ 230°C
PCB bottom side @ 260°C
3. Wave solder 255°C, 1.2
meters/min line speed
4. Hot Water Wash
1st: 30°C 45 seconds
2nd: 70°C 90 seconds
5. Rinse
1st: 23°C 45 seconds
2nd: 23°C 45 seconds
6. Dry
1st: 80°C 105 seconds
2nd: 95°C 105 seconds
Typical Interface
CH A
HEDS–9700
CH B
HCTL-2016/2020
QUADRATURE
DECODER/
COUNTER
HOST
PROCESSOR
10
Ordering Information
HEDS-97
0 – Rotary
2 – Linear
Lead Bend
0 – Straight Leads
1 – Bent Leads
Option
Resolution Options
(11 mm optical radius, Rop)
K – 96 CPR
C – 100 CPR
D – 192 CPR
E – 200 CPR
F – 256 CPR
G – 360 CPR
H – 400 CPR
(Linear)
L – 120 LPI
M – 127 LPI
Contact
P – 150 LPI
Factory for
Other
Resolution
Options
Note: Please contact factory for codewheel and codestrip information.
Mounting Options
50 – Standard
51 – Rounded Outline
52 – Backplane
53 – Standard w/Posts
54 – Tabless
55 – Backplane w/Posts
www.semiconductor.agilent.com
Data subject to change.
Copyright © 1999 Agilent Technologies, Inc.
Obsoletes 5954-2228 (10/89), 5091-9992E
(11/93)
5965-5896E (11/99)