AEDS-9641-210 Avago Technologies US Inc., AEDS-9641-210 Datasheet - Page 2

• Manufacturer Part Number: AEDS-9641-210
• Description: ENCODER DGTL 2CH 300LPI BENT LD
• Manufacturer: Avago Technologies US Inc.
• Series: AEDS-964xr

Specifications of AEDS-9641-210

• Termination Style: Terminal Pins
• Encoder Type: Optical
• Output Type: Quadrature (Incremental)
• Pulses Per Revolution: 300 LPI
• Voltage - Supply: 3.3VDC
• Actuator Type: Codestrip Not Included
• Detent: No
• Built In Switch: No
• Mounting Type: Chassis Mount
• Orientation: Right Angle
• Number Of Channels: 2
• Mounting Style: PCB
• Output: Quadrature
• Supply Voltage: 3.3 V, 5 V
• Operating Temperature Range: 0 C to + 70 C
• Product: Optical
• Technology: Linear and Rotary
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Rotational Life (cycles Min): -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Theory of Operation
The AEDS-964X 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 two-channel
digital output.
As seen in the Figure 1, the module contains a single
Light Emitting Diode (LED) as its light source. The light
is collimated into parallel beam by means of a single
lens located directly over the LED. Opposite the emitter
are the integrated detector circuits.
This IC consists of multiple sets of photodetectors and
a 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 codehweel/
codestrip. The photodiodes that detect these
interruptions are arranged in a pattern that
corresponds to the radius and count density of the
codewheel/0codestrip.
These detectors are also spaced such that a light period
on one pair of detectors corresponds to a dark period
on the adjacent pairs 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 output of channel A
is in quadrature with Channel B (90 degrees out of
phase).
2
Definitions
Note: Refer to Figure 1 for the output waveform
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)
1 shaft Rotation = 360 degrees
1 cycle (c) = 360 electrical degree, equivalent to 1 bar
and window pair.
Pulse Width (P): The number of electrical degree that
an output is high during one 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.
State Width Error (∆ ∆ ∆ ∆ ∆ S): The deviation, in electrical
degrees of each state width from its ideal value of 90°
Phase (f): 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.
Phase Error (∆φ
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.
Optical Radius (Rop): The distance from the
codewheel’s center of the rotation to the optical center
(O.C) of the encoder modules.
Angular Misalignment Error (E
misalignment of the sensor in relation to the tangential
direction. This applies for both rotary and linear motion.
Mounting Position (R
center of rotation to center of Alignment Tab receiving
hole.
∆φ
∆φ
∆φ
∆φ): the deviation of the phase from its
= N cycles
M
): Distance from Motor Shaft
A
): Angular