AEDR-8310-1V0 Avago Technologies US Inc., AEDR-8310-1V0 Datasheet - Page 2

• Manufacturer Part Number: AEDR-8310-1V0
• Description: Encoders 1 Channel 36LPI
• Manufacturer: Avago Technologies US Inc.
• Series: -r

Specifications of AEDR-8310-1V0

• Mounting Style: SMD/SMT
• Sensing Distance: 0.079" (2mm)
• Sensing Method: Reflective
• Sensing Object: Codewheel/Codestrip
• Output Configuration: -
• Sensing Light: -
• Mounting Type: Surface Mount
• Current - Supply: 2.2mA
• Voltage - Supply: 4.5 V ~ 5.5 V
• Package / Case: 5.12mm L x 3.96mm W x 1.63mm H
• Features: Compact Model
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Theory of Operation
The AEDR-8300 series combines an emitter and a detec-
tor in a single surface mount leadless package. When
used with a codewheel or linear codestrip, the encoder
translates rotary or linear motion into digital outputs.
As seen in the block diagram, the AEDR-8300 consists
of three major components: a light emitting diode (LED)
light source, a detector IC consisting photodiodes and
lens to focus light beam from the emitter as well as light
falling on the detector.
The operation of the encoder is based on the principle
of optics where the detector photodiodes sense the ab-
sence and presence of light. In this case, the rotary/lin-
ear motion of an object being monitored is converted
to equivalent light pattern via the use of codewheel/
codestrip. As shown in the diagram below, the reflective
area (window) of the codewheel (or codestrip) reflects
light back to the photodetector IC, whereas no light is
reflected by the non-reflective area (bar). An alternating
light and dark patterns corresponding to the window
and bar fall on the photodiodes as the codewheel ro-
tates. The moving light pattern is exploited by the de-
tector circuitry to produce digital outputs representing
the rotation of the codewheel. When the codewheel is
coupled to a motor, the encoder outputs is then a direct
representation of the motor rotation. The same concept
applies to the use of a codestrip to detect linear motion.
V
CH A
CH B
Figure 1. Block Diagram of AEDR-8300.
2
GND
GND
V
LED
CC
PROCESSING
CIRCUITRY
SIGNAL
R
AEDR-8300 block diag
Definitions
State Width (S): The number of electrical degrees be-
tween a transition in Channel A and the neighboring
transition in Channel B. There are 4 states per cycle,
each nominally 90
State Width Error (∆S): The deviation of state width, in
electrical degree, from its ideal value of 90
Phase (φ): The number of electrical degrees between
the center of high state of Channel A and the center of
high state of Channel B. Nominally 90
Phase Error (∆φ): The deviation of phase, in electrical
degree, from its ideal value of 90
Pulse Width (P): The duration of high state of the out-
put, in electrical degree, within one cycle. Nominally
180
Pulse Width Error (∆P): The deviation of pulse width, in
electrical degree, from its ideal value of 180
Count (N): The number of window and bar pair per rev-
olution (CPR) of codewheel. For linear codestrip, defined
as the number of window and bar pair per unit length
(lines per inch [LPI] or lines per mm [LPmm]).
One Cycle (C): 360 electrical degrees (
one window and bar pair.
CODEWHEE L
OR
CODESTRIP
o
e or half a cycle.
o
e.
o
e.
o
e.
o
e). Equivalent to
o
e.
o
e.