AVAGO HEDS-8940

AEDA-3200-Txx Series
Ultra Miniature, High Resolution ­Incremental Encoders
Data Sheet
Description
Features
The AEDA-3200-T series (top mounting type) are high
­performance, cost effective, three-channel optical
­incremental encoder modules.
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AEDA-3200-T series emphasize high reliability, high resolution and easy assembly, using transmissive encoder technology to sense rotary position. Outputs of the AEDA-3200
encoders are two channel quadrature outputs and a third
channel gated index output. These encoder modules can
be easily mounted to ­customer specific applications with
the specially ­designed mechanical alignment tool.
Two channel quadrature output with index
Quick and easy assembly with alignment tool
Cost-effective
Ultra miniature size (ø17 mm)
Resolution options from 2500 to 7500 Cycles Per
­Revolution (CPR), up to 30000 counts with 4X decoding
• Integrated RS 422 differential line driver
Outline Drawing
Theory of Operation
The AEDA-3200 translates rotary motion of a shaft into a
three channel digital output. The AEDA-3200 series has
five key parts: a single light emitting diode (LED) light
source, a photodetector IC with a set of uniquely configured photodiodes, an interpolator IC, a line driver IC and
a pair of lenses.
This light is used to produce internal signals A and A-,
and B and B-.
Output Waveforms
As part of the “push-pull” detector system, these signals
are fed through comparators and line driver that are part
of the signal processing circuitry to produce the final
outputs for channels A.
The AEDA-3200 is available for cycles per revolution (CPR)
of 2500 to 7500. This translates to a maximum resolution
of 30000 counts after quadrature decode (4X).
Definitions
Direction of Motor Rotation
Count (N): N refers to the cycles per revolution (CPR) of the
encoder output.
When the codewheel rotates in a clockwise direction,
channel A will lead channel B (Figure 1 illustrates the definition of clockwise direction of codewheel rotation). When
the codewheel rotates in a counter-clockwise direction,
channel B will lead channel A.
One Cycle (C): 360 electrical degrees (°e).
One Shaft Rotation: 360 ­mechanical degrees, N cycles (rotary
motion only).
Phase (φ): The number of electrical degrees between the
center of the high state on the channel A and the center of
the high state of channel B. This value is nominally 90°e.
Pulse Width (P): The number of the electrical degrees that an
output is a high-level during one cycle, nominally 180°e
or 1/2 a cycle.
Pulse Width Error (∆P): The deviation in electrical degrees of
the pulse width from its ideal value of 180°e.
Index Pulse Width (Po): The number of electrical degrees that
an index is high during one full shaft rotation. This value
is nominally 90°e or 1/4 cycle.
State Width (S): The number of the electrical degrees between a transition in the output of the 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.
Figure 1. Viewed from the PCB encoder end.
Absolute Maximum Ratings
Storage Temperature
-40°C to 125°C
Operating Temperature
-40°C to 125°C
Supply Voltage
4.5 V to 5.5 V
Output Voltage
-0.5 V to Vcc
Output Current per Channel
20 mA
Frequency
750 kHz
Recommended Operating Conditions
Parameter
Symbol
Min.
Typical
Max.
Units
Notes
Temperature
TA
-40
25
125
°C
Supply Voltage
VCC
4.5
5.0
5.5
Volts
Ripple <100 mVp-p
Frequency
f
125
750
kHz
f = RPM x CPR
60
Maximum Frequency and RPM
CPR
Maximum Frequency (kHz)
Maximum RPM2
2500
750 1
12000 5000
750
9000
6000
750
7500
7200
750
6250
7500
750
6000
Note:
1. Maximum frequency will be lower due to limitation in maximum RPM.
2. Maximum mechanical limit is 12000 RPM, operating limit is dependent on the maximum operating frequency.
Electrical Characteristics
Electrical characteristics over recommended operating conditions. Typical values at 25oC.
Parameter
Symbol
Supply Current
Min.
Typical
Max.
Units
ICC
55
80
mA
High level Output Voltage
VOH
3.4
V
Low level Output Voltage
VOL
0.3
V
2.5
0.5
Encoding Characteristics
Encoding characteristics over recommended operating conditions. Typical values at 25oC.
Parameter
Symbol
Typical
Max.
Units
Pulse Width Error
∆P
5
85
°e
State Width Error
∆S
5
60
°e
Phase Error
∆φ
1
40
°e
Mechanical Characteristics
(Refer to page 2 for details.)
Parameter
Dimension/Details
Tolerance
Standard Shaft Diameters
2 mm diameter maximum *
-.002/-.007 (-.0001/-.0003) mm (in)
Mounting Screw Size:
M2.5 x 0.45 (Recommended Length 6 mm)
* Note:
1. Using a step shaft, maximum shaft diameter is 4 mm.
Units
mm
Pin Assignments
Pin
Signal
Description
Pin 1
A+
Digital Output
Pin 2A­-
Digital Output
Pin 3
Gnd
Ground Pin
Pin 4
Gnd
Ground Pin
Pin 5
B+
Digital Output
Pin 6
B-
Digital Output
Pin 7
Vcc
Input Voltage
Pin 8
Vcc
Input Voltage
Pin 9
I+
Digital Output
Pin 10
I-
Digital Output
Notes:
1. Both Pin 7 and Pin 8 must be connected to Vcc.
2. Either Pin 3 or Pin 4 must be connected to Gnd.
Mating Connector
Alignment Considerations
AEDA-3200 requires a 5 x 2 (1.27 mm x 1.27 mm) female
IDC Connector. An example of the suggested mating
connectors is Samtec (www.samtec.com) part number:
FFSD-05-D-x-01-N. The cable used is 0.635 mm pitch flat
ribbon cable.
The mechanical alignment tool is ­intended to absorb normal
installation misalignment and runouts. To achieve the optimum performance, user should minimize misalignment.
Electrical Interface
Avago recommends National Semiconductor DS26C32AM
Quad Differential Line Receiver or compatible as line receiver. Unused pin should be grounded for noise reduction.
Complete instructions for AEDA-3200 installation can
be found in Application Note 5080, Avago AEDA-3200-T
Mechanical Mounting and Installation Consideration.
AEDA-3200 Mechanical Alignment tool part number is
HEDS-8940.
HEDS-8940 Mechanical Alignment Tool.
Ordering Information
AEDA-3200- T
Resolution Options (CPR)
AJ
2,500
B1
5,000
B7
6,000
BJ
7,200
BK
7,500
Alignment Tool Remark
HEDS-8940
Mechanical Alignment Tool
Counts After 4x Decoding
10,000
20,000
24,000
28,800
30,000
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, Limited in the United States and other countries.
Data subject to change. Copyright © 2006 Avago Technologies, Limited. All rights reserved. Obsoletes AV01-0175EN
AV01-0619EN - November 1, 2006