HEDB-9040 and HEDB-9140 Three Channel Optical Incremental Encoder Modules Bundle With Codewheel Data Sheet Description Features The HEDB-9040 and HEDB-9140 series are three channel optical incremental encoder modules offered with a codewheel. When used with a codewheel, these low cost modules detect rotary position. Each module consists of a lensed LED source and a detector IC enclosed in a small plastic package. Due to a highly collimated light source and a unique photodetector array, these modules are extremely tolerant to mounting misalignment. Two Channel Quadrature Output with Index Pulse The HEDB-9040 and 9140 has two channel quadrature outputs plus a third channel index output. This index output is a 90 electrical degree high true index pulse which is generated once for each full rotation of the codewheel. Operating Temperature: -40°C to 100°C The HEDB-9040 is designed for use with a HEDS-6140 codewheel which has an optical radius of 23.36 mm (0.920 inch). The HEDB-9140 is designed for use with a HEDS-5140 codewheel which has an optical radius of 11.00 mm (0.433 inch). The quadrature signals and the index pulse are accessed through five 0.025 inch square pins located on 0.1 inch (pitch) centers. Resolution from 100 CPR Up To 1024 CPR (Counts Per Revolution) Low Cost Easy to Mount No Signal Adjustment required Small Size TTL Compatible Single 5V Supply Applications The HEDB-9040 and 9140 provide sophisticated motion control detection at a low cost, making them ideal for high volume applications. Typical applications include printers, plotters, tape drives, and industrial and factory automation equipment. Note: Avago Technologies encoders are not recommended for use in safety critical applications. Eg. ABS braking systems, power steering, life support systems and critical care medical equipment. Please contact sales representative if more clarification is needed. Theory of Operation The HEDB-9040 and 9140 is emitter/detector modules. Coupled with a codewheel, these modules translate the rotary motion of a shaft into a three-channel digital output. Cycle Error (C): An indication of cycle uniformity. The difference between an observed shaft angle which gives rise to one electrical cycle, and the nominal angular increment of 1/N of a revolution. As seen in Figure 1, the modules contain a single Light Emitting Diode (LED) as its light source. The light is collimated into a parallel beam by means of a single polycarbonate lens located directly over the LED. Opposite the emitter is the integrated detector circuit. This IC consists of multiple sets of photodetectors and the signal processing circuitry necessary to produce the digital waveforms. Pulse Width (P): The number of electrical degrees that an output is high during 1 cycle. This value is nominally 180°e or 1/2 cycle. The codewheel rotates between the emitter and detector, causing the light beam to be interrupted by the pattern of spaces and bars on the codewheel. The photodiodes which detect these interruptions are arranged in a pattern that corresponds to the radius and design of the code-wheel. These detectors are also spaced such that a light period on one pair of detectors corresponds to a dark period on the adjacent pair of detectors. The photodiode outputs are then fed through the signal processing circuitry resulting in A, Abar, B, Bbar, I and Ibar. Comparators receive these signals and produce the final outputs for channels A and B. Due to this integrated phasing technique, the digital output of channel A is in quadrature with that of channel B (90 degrees out of phase). Definitions Note: Refer to Figure 2 Count (N): The number of bar and window pairs or counts per revolution (CPR) of the codewheel. One Cycle (C): 360 electrical degrees (°e), 1 bar and window pair. One Shaft Rotation: 360 mechanical degrees, N cycles. Position Error (): The normalized angular difference between the actual shaft position and the position indicated by the encoder cycle count. 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. Phase (): 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. This value is nominally 90°e for quadrature output. Phase Error (): The deviation of the phase from its ideal value of 90°e. Direction of Rotation: When the codewheel rotates in the clockwise direction viewing from top of the module (direction from V to G), channel A will lead channel B. If the codewheel rotates in the opposite direction, channel B will lead channel A. Optical Radius (Rop): The distance from the codewheel’s center of rotation to the optical center (O.C) of the encoder module. Index Pulse Width (Po): The number of electrical degrees that an index is high during one full shaft rotation. This value is nominally 90°e or 1/4 cycle. Specification For encoder electrical, mechanical specifications, codewheel technical specifications and additional informations please refer to : HEDS-9040 /9140 datasheet. HEDS/HEDG/HEDM – 51xx/61xx Codewheel Datasheet 2 Block Diagram RESISTOR VCC PHOTO DIODES COMPARATORS LENS A A B LED B I I + + CODE WHEEL CH. B − + − SIGNAL PROCESSING CIRCUITRY EMITTER SECTION CH. A − CH. I INDEXPROCESSING CIRCUITRY GND DETECTOR SECTION Figure 1. Block Diagram Output Waveforms C P 2.4 V 0.4 V AMPLITUDE φ S1 S2 S3 S4 2.4 V 0.4 V t2 t1 2.4 V 0.4 V P0 ROTATION Figure 2. Output waveforms 3 CH. A CH. B CH. I Ordering Information Three Channel Encoder Modules with Codewheel, 11 mm and 23.36 Optical Radius 40 - HEDB - 9 Codewheel Rop Resolutions (Cycle/Rev) Shaft Diameter 0 - 23.36 mm 1 - 11.00 mm K - 96 CPR C - 100 CPR E - 200 CPR F - 256 CPR G - 360 CPR H - 400 CPR A - 500 CPR I - 512 CPR B - 1000 CPR J - 1024 CPR 02 - 3mm 03 - 1/8 in 04 - 5/32 in 05 - 3/16 in 06 - 1/4 in 08 - 3/8 in 09 - 1/2 in 10 - 5/8 in 11 - 4mm 12 - 6mm 13 - 8mm 14 - 5mm Available Options Shaft Diameter Options Part Number CPR HEDB-9140 C 02 03 04 05 06 08 09 10 11 E F G H A I 12 13 14 14 Shaft Diameter Options Part Number CPR HEDB-9040 4 02 03 04 05 06 08 09 10 11 12 13 B J Bundle Part Number Breakdown List HEDB - 9040 - CPR Shaft Diameter CPR Encoder Module : HEDS-9040 Codewheel : HEDS - 6140 - HEDB - 9140 - CPR CPR 00 Shaft Diameter Shaft Diameter Encoder Module : HEDS-9140 Codewheel : HEDS - 5140 - CPR CPR 00 Shaft Diameter Note : The bundle part HEDB-9040/9140 consists of HEDS-9040/9140 and HEDS-6140/5140. The table below provides the breakdown list. For product information and a complete list of distributors, please go to our web site: www.avagotech.com Avago, Avago Technologies, and the A logo are trademarks of Avago Technologies in the United States and other countries. Data subject to change. Copyright © 2005-2012 Avago Technologies. All rights reserved. Obsoletes 5989-4043EN AV02-3607EN - June 12, 2012