HEDR-80002K AVAGO [AVAGO TECHNOLOGIES LIMITED], HEDR-80002K Datasheet - Page 3

• Manufacturer Part Number: HEDR-80002K
• Description: Reflective Optical Surface Mount Encoders
• Manufacturer: AVAGO [AVAGO TECHNOLOGIES LIMITED]

Definitions
Count (N): For rotary motion,
the number of bar and window
pairs or counts per revolution
(CPR) of the codewheel. For
linear motion, the number of bar
and window pairs per unit length
(lines per inch [LPI] or lines per
mm [LPmm]).
One Cycle (C): 360 electrical
degrees ( e), 1 bar and window
pair.
One Shaft Rotation: 360
mechanical degrees, N cycles
(rotary motion only).
Line Density: The number of
reflective and non-reflective pairs
per unit length, expressed as
either lines per inch (LPI) or lines
per mm (LPmm).
3
Output Waveforms
AMPLITUDE
CODEWHEEL
RADIAL
SHAFT
HEDR-8000
CODEWHEEL ROTATION OR LINEAR MOVEMENT
TANGENTIAL
S1
P
S2
C
S3
S4
Pulse Width (P): The number of
electrical degrees that an output
is high 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.
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 e.
CODEWHEEL
SHAFT
ALL FOUR STATES (S1 TO S4)
ARE MAINTAINED.
HEDR-8000
E
A
CH. A
CH. B
Phase ( ): The number of
electrical degrees between the
center of the high state on channel
A and the center of the high state
on channel B. This value is
nominally 90 e.
Phase Error (
in electrical degrees of the phase
from its ideal value of 90 e.
Direction of Rotation: When the
codewheel or codestrip moves in
the direction from pin 1 to pin 4,
as viewed when looking down on
the lenses, channel B will lead
channel A. If the codewheel or
codestrip moves in the opposite
direction, channel A will lead
channel B.
Optical Radius (Rop): For rotary
motion, the distance from the
codewheel’s center of rotation to
the center line connecting the two
lenses of the encoder.
Gap (G): The distance from the
top of the package to the surface of
the reflective codewheel or
codestrip.
Specular Reflectance (R
measure of a surface’s reflective
finish. This is quantified by the
amount of light reflected when hit
with an incident beam. A device
called a scatterometer is used to
quantify specular reflectance on a
percent scale. (Contact factory for
more information.)
Radial and Tangential
Misalignment Error (E
For rotary motion, mechanical
misalignment in the radial and
tangential directions relative to the
codewheel.
Angular Misalignment Error
(E
sensor in relation to the tangential
direction. This applies for both
rotary and linear motion.
A
): angular misalignment of the
): The deviation
R
, E
f
): a
T
):