*RoHS Directive 2002/95/EC Jan 27 2003 including Annex
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
EN - Rotary Optical Encoder
Features
■Two channel quadrature output
■Bushing or servo mount
■Square wave signal
■Index channel available
■Small size
■Resolution to 256 PPR
■CMOS and TTL compatible
■Long life
■High operating speed
Electrical Characteristics
Output ..............................................................................................2-bit gray code, Channel A leads Channel B by 90 º (electrical) with clockwise rotation
Resolution ..................................................................................................................................................................................25 to 256 cycles per revolution
Insulation Resistance (500 VDC) ......................................................................................................................................................................1,000 megohms
Electrical Travel ........................................................................................................................................................................................................Continuous
Supply Voltage ..........................................................................................................................................................................................5.0 VDC ±0.25 VDC*
Supply Current ................................................................................................................................................................................................26 mA maximum
Output Voltage
Low Output ....................................................................................................................................................................................................0.8 V maximum
High Output........................................................................................................................................................................................................4 V minimum
Output Current
Low Output ..................................................................................................................................................................................................25 mA minimum
Rise/Fall Time......................................................................................................................................................................................................200 ns (typical)
Shaft RPM (Ball Bearing)............................................................................................................................................................................3,000 rpm maximum
Power Consumption......................................................................................................................................................................................136 mW maximum
Pulse Width (Electrical Degrees, Each Channel) ..............................................................................................................................................180 º ±45 º TYP.
Pulse Width (Index Channel) ....................................................................................................................................................................................360 º ±90 º
Phase (Electrical Degrees, Channel A to Channel B)..........................................................................................................................................90 º ±45 º TYP.
Index Channel Centered on 1-1 State Combination of A and B Channels ..................................................................................................................0 º ±45 º
*Consult factory for other voltages up to 5 VDC.
Environmental Characteristics
Operating Temperature Range ..........................................................................................................................................-40 ºC to +75 ºC (-40 °F to +167 °F)
Storage Temperature Range ............................................................................................................................................-40 °C to +85 °C (-40 °F to +185 °F)
Humidity....................................................................................................................................................................MIL-STD-202, Method 103B, Condition B
Vibration ................................................................................................................................................................................................................................5 G
Shock ..................................................................................................................................................................................................................................50 G
Rotational Life
A & C Bushings (300 rpm maximum)** ..............................................................................................................................................10,000,000 revolutions
W, S & T Bushings (3,000 rpm maximum)** ....................................................................................................................................200,000,000 revolutions
IP Rating..............................................................................................................................................................................................................................IP 40
Mechanical Characteristics
Mechanical Angle ............................................................................................................................................................................................360 ° Continuous
Torque (Starting and Running)
A & C Bushings (Spring Loaded for Optimum Feel) ................................................................................................................1 N-cm (1.5 oz-in.) maximum
W, S & T Bushings (Ball Bearing Shaft Support) ................................................................................................................0.07 N-cm (0.1 oz-in.) maximum
Mounting Torque ....................................................................................................................................................1.7 to 2.0 N-cm (15 to 18 lb.-in.) maximum
Shaft End Play ......................................................................................................................................................................0.30 mm (0.012 ”) T.I.R. maximum
Shaft Radial Play ..................................................................................................................................................................0.12 mm (0.005 ”) T.I.R. maximum
Weight ..............................................................................................................................................................................................................11 gms. (0.4 oz.)
Terminals ........................................................................................................................................................................Axial or radial pc pins or ribbon cable
Soldering Condition
Manual Soldering ....................................................................................................................96.5Sn/3.0Ag/0.5Cu solid wire or no-clean rosin cored wire
370 °C (700 °F) max. for 3 seconds
Wave Soldering ..............................................................................................................................................96.5Sn/3.0Ag/0.5Cu solder with no-clean flux
260 °C (500 °F) max. for 5 seconds
Wash processes ........................................................................................................................................................................................Not recommended
Marking ..................................................................................................................................Manufacturer’s trademark, name, part number, and date code.
Hardware ..................................................................One lockwasher and one mounting nut supplied with each encoder, except on servo mount versions.
**For resolutions ≤ 128 quadrature cycles per shaft revolution.
*RoHS COMPLIANT
VERSIONS
AVAILABLE
Quadrature Output Table
OUTPUT VOLTAGE
Channel A
Channel B
Index
Channel
(Optional)
4.0 V (Min)
0.8 V (Max)
4.0 V (Min)
0.8 V (Max)
4.0 V (Min)
0.8 V (Max)
1
0
1
0
1
0
1 cycle
Clockwise rotation
360 ° ± 90 °
STANDARD RESOLUTIONS AVAILABLE
(Full quadrature output cycles per shaft revolution)
25* 125
50* 128
64 200
100 256
For Non-Standard Resolutions—Consult Factory
* Channel B leads Channel A
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Dimensional Drawings
Optional
Radial Leads
A
-+
B
GROUND
INDEX
OR
N.C. Vcc CHANNEL B
CHANNEL A
TERMINATION DIAGRAM
2.54
(.100) TYP. SQ.
1/4-32 UNEF
DIA.
3/8-32 UNEF
3/8-32 UNEF 1/4-32 UNEF
Optional
Radial Leads
Bushing Style C
Bushing Style S
(Ball Bearing)
Bushing Style AShaft End Style C
Bushing Style T
(Ball Bearing)
Servo Mount Style W (Ball Bearing)
9.525
(.375)
.635
(.025)
18.5
(.73) 6.35
(.250)
6.34
(.2497)
5.54
(.218)
F
3.167 + .000/ – .0076
(.1247 + .000/ – .0003)
8.636
(.34 )
4 PLCS.
2 PLCS.
Recommended Board Layout
with Bracket
Bushing with Bracket Side Exit
Ribbon Cable Option
Rear Exit Ribbon Cable Option
Side Exit
Ribbon Cable Option Detail
Connector
Pinout Connector
Pinout
18.11
(.713)
11.13
(.438) 4.14
(.163)
2.54
(.100)
6.99
(.275)
9 PLCS. DIA. MIN.
0.99
(.039)
15.88
(.625)
1.37
(.054)
21.21
(.835)
2.36
(.093)
9.53
(.375)
6.342 + .000/ – .0076
(.2497 + .000/ – .0003)
10.32 + .000/ – .0508
(.4062 + .000/ – .002)
9.53
(.375)
9.53
(.375)
DIA.
6.342 + .000/ – .0076
(.2497 + .000/ – .0003)DIA.
1.57
(.062)
DIA.
3.167 + .000/ – .0076
(.1247 + .000/ – .003)
1.57
(.062)
9.53
(.375)
DIA.
7.14 + .000/ – .0508
(.281 + .000/ – .002) DIA.
1.57
(.062) 1.57
(.062) DIA.
3.167 + .000/ – .0076
(.1247 + .000/ – .003)
21.8
(.86)
DIA.
19.05 ± .0127
(.7500 ± .0005)
DIA.
22.2 + .0127 / – .1270
(.875 + .0005 / – .0050)
1.57
(.062) .787 ± .254
(.031 ± .010)
.254 ± .076
(.010 .003)
R.
Anti-rotation Lug
View
SHAFT
LENGTH
SHAFT FLAT
LENGTH
(DIM. F)
12.7
(.050)
15.9
(.625)
19.1
(.750)
2.54
(.100)
5.08
(.200)
8.25
(.325)
A—+B
5
4
3
2
1
5
4
3
2
1
Consult factory for options not shown,
including:
• Wire lead or cable options
• Connectors
• Non-standard resolutions
• Special shaft/bushing sizes and
features
• Special performance characteristics
• PCB mounting bracket
EN - Rotary Optical Encoder
GENERAL INFORMATION
The Bourns®EN model is a self-contained rotary optical encoder. It
produces a 2-bit quadrature signal which is suitable for digital systems
where both magnitude and direction of adjustment must be provided.
The EN encoder is ideal for use as a digital panel control or as a position
sensing device in applications where long life, reliability, high resolution
and precise linearity are critical.
The EN series encoder converts rotary input into electrical signals
which can be used by microprocessors without A/D conversion.
Bourns encoder output signals are square wave digital pulses which do
not require debounce circuitry. Both features make it possible to
significantly reduce the memory overhead, wiring and wiring
interconnects required by other types of control devices.
EN optical encoders offer a useful rotational life of from 10 million to
200 million shaft revolutions, making them ideal for extended service
applications. The Bourns encoder is also compact and well suited for
situations where the available space is limited.
MM
DIMENSIONS: (IN.)
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
EN - Rotary Optical Encoder
How To Order
BOURNS EN SERIES OPTICAL ENCODER
ENC1J-B28-L00128L
ANTI-ROTATION
LUG POSITION
Code
D
J
P
Description
None
9:00 Position
Rear Mount-
ing Bracket
SHAFT LENGTH*
Code
16
20
28
Description
1/2 " Long
5/8 " Long
7/8 " Long
RoHS IDENTIFIER
Code
L
Blank
Description
Compliant
Non-Compliant
SWITCHING
CONFIGURATION
Code
1
2
Description
Channel A
Leads
Channel B
By 90 °
(Clockwise
Rotation)**
Code 1
Switching
With Index
Channel
TERMINAL***
CONFIGURATION
Code
L
R
M
N
W
Y
Description
Axial, Multi-
Purpose Pin
Radial, Multi-
Purpose Pin
Axial, Ribbon
& Connector
10 "
Radial, Ribbon
& Connector
10 "
Axial, Ribbon
10 " -
No Connector
Radial, Ribbon
10 " -
No Connector
RESOLUTION
Code
00025
00050
00064
00100
00125
00128
00200
00256
Cycles Per
Revolution
25
50
64
100
125
128
200
256
SHAFT STYLE
Code
B
D
C
Use With
Bushings (Code)
A, S
C, T, W
A, S
Description
1/4 " Dia., Plain End
1/8 " Dia., Plain End
1/4 " Dia., Single
Flatted
BUSHING CONFIGURATION
Code
A
C
S
T
W
Description
3/8 "D X 3/8 "L Threaded
1/4 "D X 1/4 "L Threaded
3/8 "D X 3/8 "L Threaded
(Ball Bearing)
1/4 "D X 3/8 "L Threaded
(Ball Bearing)
Servo Mount 7/8 "D
(Ball Bearing)
* Shaft length measured from mounting surface.
** 25 and 50 ppr is reversed (Channel B leads Channel A)
*** Standard ribbon cable is 10 " long
Consult factory for other lengths.
REV. 08/06
