sensors Optical Encoder System EOI R007 highly accurate and small ELESTA introduced a new optical, 3-channel encoder system. This system meets the growing demand for miniaturization of micromechanical drives. Additionally the system offers higher precision in controlling motor speed and position. ELESTA sensors Elesta selected the reflective mode of operation for this unique design. Light source and photo detector are mounted in the same plane facing the code wheel. The unique design of the code wheel is such that the complete surface of the wheel is reflective. This ensures that nearly all of the incoming light, from the light source, is reflected on the light sensor. This patented feature resulted in an encoder of compact design, with extremely low power consumption, high resolution and precise output signals. The flexibility of this encoder system allows it to be integrated into a variety of housings of systems and motors with ease. Efficient use of light energy The uniquely shaped reflective surface of the encoder wheel reflects and focuses light emitted by the light source on the light sensor. code wheel light source Extremely high accuracy High resolution The precision of the code wheel, the focusing of the light beam and the use of a CMOS control circuit achieved a high slew rate and very tight signal tolerances. The specification below is based on a code wheel with 128 reflectors and achieved an angular tolerance of less than ± 0.14°. This proves that the design of miniaturized precise angle sensors is possible and efficient. The unique design of the code wheel enables the ELESTA system to achieve higher signal selectivity than comparable reflective systems. This lies in the fact that the light efficiency of the ELESTA design is a factor two better than most of the comparable systems. The high precision of the output signals allows the system to retain its accuracy after 2-fold and 4-fold interpolation. light sensor More than 90% of light emitted by the light source arrives at the light sensor for signal generation. This allows the implementation of low level light sources, which in turn drastically reduces the power consumption of the entire system. The ELESTA encoder system is well suited for off-grid systems and mobile devices. Reliability Thanks to the patented sensing system position, tolerances between code wheel and sensors have little or no influence on the accuracy of the sensor output signals. This is an advantage over most other comparable systems and improved the reliability of the ELESTA system as a whole. Extreme environmental conditions have minimal affects on the signal quality. Coupled with the feature of individual design options, easy integration with customer specific products and the miniaturized footprint this encoder is ideally suited for high reliability applications. Modular system The accuracy of outputs are highly immune to the positional tolerance between code wheel and sensor. This allows ELESTA to provide an encoder as a modular system in kit form. Customers have the option to integrate the sensor and code wheel kit in an existing housing, motor or system. Alternatively customers may integrate the encoder system as a universal encoder in a preferred housing. Accessories allow customers the capability to adapt the universal encoder to their system. Customized solutions ELESTA has the capability to develop customer specific solutions and to adapt the encoder design to meet customer application requirements. Datasheet EOIR007 C0128 DSET SA CMOS FC1 Dimensions and Pin Configuration -- Incremental optical encoder -- Unique code wheel design -- High precision reflective system -- Low current consumption -- Easy assembly -- Very compact mounting form -- High immunity to positional tolerance between code wheel and sensor 2.7 Rigid flex (flexible part) 0.1 Rigid flex (rigid part) Mechanical Specifications Signal Diagram Operating temperature Storage temperature Relative humidity (without condensation) Shock stability (EN 60068-2-27) Vibration resistance (EN 60068-2-6) Recommended connector: 0.5mm ZIF/LIF (thickness 0.3mm) CW T4 T3 T2 T1 Direction Switching CCW T1 T2 T3 T4 A CW CCW B a2 Z 1/Rev Index Pulse -20°C to 85°C -20°C to 85°C 85% half sin, 30g, 6ms 5Hz-120Hz Amp. 1mm, 5min 0.3 3.5 *valid for typical distance of 0.3mm between code wheel and sensor Environmental Specifications 1) NC 2) VSS 3) Z 4) B 5) A 6) VDD 8.9 0.3 Detailed dimensions on request 4.4mm 1.1mm 128 1.5mm max. ±0.2mm 0.2mm...1.2mm Ø 1.5 Ø 4.4 4 82.8 (after calibration) Code wheel diameter Code wheel thickness Resolution (code wheel lines) For shaft diameter X, Y position tolerances Distance code wheel/sensor 128 Lines 0.35 0 0.5 1 1.5 2 2.5 3 3.5 for Shaft Diameter Ø1.5 Electrical Specifications Supply voltage 3V...6V Supply current* 2mA...6mA Output short circuit current max. 30mA Output drive current (at 4.5V) typ. 5mA Speed24‘000RPM Frequency typ. 1‘000kHz Signal rise/fall time (RL=1kΩ, CL=47pF)typ. 300ns 3 channels A, B, Z Signal output CMOS/TTL Duty cycle for A and B 50% ±5% Phase between A and B 90°e ±5°e Burst (EN-61000-4-4) ±1kV ESD (EN-61000-4-2) ±4kV / ±8kV Isolation values on request 1 Area (Index) Rigid flex (rigid part) Ø4.4 (3.05 to 4.05) 0.2 to 1.2 Codewheel 1.75 2 1.1 6. Ø 4 Features Output Circuit 1/Rev Index Pulse Duty = W C C IN OUT In preparation CW GND Product Key EOIR007 C0128 DSET SA CMOS FC1 Connection Signal output Pulse multiplication factor 1 Single-Turn Set encoder/code wheel Number of codelines Series a1 a1 + a2 x 100% Rotation Direction Identification VDD Tests and Regulations a1 CMOS-Inverter CW - Clockwise CCW - Counterclockwise Options Accessories In preparation In preparation Phone: +41 (0)81 303 54 00 Fax: +41 (0)81 303 54 01 E-Mail: [email protected] Web: www.elesta-gmbh.com ELESTA GmbH Heuteilstrasse 18 CH-7310 Bad Ragaz Switzerland