Why an Encoder 252 Spotlight on MR2 Encoder 253 Encoder Specifications 256

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1 Encoders Feedback mechanisms for gauging motor position and speed are highly essential for a wide range of applications in medical, industrial automation, security and access. Portescap s encoder technologies spanning from the simplest tachogenerators to highly sophisticated MR encoders provide a bundle of solutions for positioning and speed related feedback to facilitate the needs of motion in a variety of applications. Why an Encoder 252 Spotlight on MR2 Encoder 253 Encoder Specifications 256

2 Why an Encoder Asic LED Codewheel Feedback & Positioning D.C. TACHOGENERATORS MAGNETIC ENCODERS The combination of an ironless rotor, a high grade permanent The integrated Portescap type D magnetic encoder consists of magnet, and a commutation system made of precious metals, a multipolar magnet mounted directly on the motor shaft. As results in Portescap DC tachogenerators having a truly linear the motor shaft turns, magnetic flux variations are detected by relationship between angular velocity and induced voltage, a Hall sensors which generate two TTL-CMOS compatible output very low moment of inertia and negligible friction. signals having a 9 phase shift between both channels. The OPTICAL ENCODERS simple and robust design of this sensor makes it ideally suited to applications with severe operating conditions, such as high The incremental optical encoders from Portescap have three temperature, dust, humidity, and vibration. Integrated into output channels. It uses a dedicated ASIC having a matrix of Portescap motors, these units are intended for applications optoelectronic sensors which receives infrared light from an requiring compact and reliable high performance systems for LED after its passage through a metal codewheel. The mask speed and position control. determining the phase angle and index position is directly integrated onto the circuit, ensuring very high precision. The differential measure of the light modulated by the codewheel generates digital output signals insensitive to temperature drift with an electrical phase shift of 9 between channels A and B. The standard version of the encoder provides CMOS compatible complementary signals for improved signal transmission and noise rejection. Besides the detection of the direction of rotation and signal transitions in channel A and B for direct control of a counter or a microprocessor, the integration of this particular circuit offers additional functions such as a stand-by mode for reduced current consumption in battery powered equipment.

3 Spotlight on MR2 encoder Magnetoresistance effect which was first discovered in 857 can be seen in three different configurations:-.r(m(t)) Resistance changes due to indirect manipulation of magnetization through thermal changes 2.R(M) Resistance changes due to direct manipulation of the magnetization. 3.R(θ M,I ) Resistance changes due to the angle between the magnetization and current The third effect, also referred to as anisotropic magnetoresistance is exploited in Portescap s high resolution MR encoders. This resistance variation responds to the following equation: ρ(θ M,I ) = ρ + ρ cos 2 (θ M,I ) where ρ is the zero-field resistivity, ρ is the minimal resistivity and θ M,I is the angle between the magnetic field and the current. The relation between resistivity and magnetic angle governs the design of the MR encoder and as such the encoder signals have negligible effect on variation in magnetic field strength. Using interpolation techniques, several output lines per revolution are generated with only one period of analog signal coming out from the sensor magnet system, in incremental magnet encoders. The pulse signal from MR encoder as shown below is proportional to speed and distance traveled by the shaft and can be used for effective feedback. A B State: Permanent Magnet As the MR technology is not needed to have physically all the output lines (poles in case of a magnetic encoder) on the encoder disc, the MR encoder can be made very compact, even for high resolution. The magnetic field inside the encoder can be maximized by having a low number of relatively big magnetic poles. The strong field so obtained makes this encoder very resistant against any unwanted external field. Also, with this compact design the encoder disc magnet remains very small thus sustaining the motor s high dynamic performances. Finally, as this encoder is made around a magnetic angle sensor, it is not sensitive to vertical position changes and, hence, ball bearings in a motor are not a prerequisite to achieve high resolution.

4 Motor End cap Encoder Chip Encoder Chip Concept Detail Encoder Characteristics Advantages for the Application Interpolated lines Field angle sensor Low thickness high field density magnet Physical line count on the encoder disc is much lower than encoder resolution High magnet field obtained with simple bipolar magnet No sensitivity to axial movement of the encoder magnet Ultra low encoder inertia Ultra compact design for high resolution ery low sensitivity to unwanted external field Ball bearing motor not required even for high resolution High dynamic performance of the motor stays intact

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6 escap Type D / Type F Integrated Magnetic Encoders dimensions in mm Encoder Type D and F connections ) Motor + 6 Motor - 2 cc 7 NC 3 Channel A 8 NC 4 Channel B 9 NC 5 GND NC Characteristics at 22ºC D F Number of pulses per rev 2 6 Supply voltage cc Supply current typical at 5 ma 4 6 Rise time t4 µs.25 5 Fall time t5 µs.5.2 Output signal 2) Two channels / square wave in quadrature Electrical phase shift between U and U2 t3/t x 36 degree 9 ± 4 Signal ratio 3) t2/t % 5 ± 25. count frequency khz 5 Operating temperature range ºC Inertia -7 x kgm 2. Temperature ºC 22 Measuring conditions Supply voltage 5 Load resistance Mohm Load capacity pf 25 Encoder F available on motor types 6C 6N 7S 7N 22N 22 L = length (mm) L2 = length (mm) 3, D = motor diameter (mm) Encoder D available on motor types 3N P.9 L = length (mm) D = motor diameter (mm) Typical Encoder Output Signal ) Connector Dupont type Quikie II or equivalent t: Period t2/t: Signal ratio t3: Phase shift t4 Rise time t5 Fall time 2) Internal pull-up resistor: kohm only available with the F type encoder 3) Over the entire frequency and temperature range 256

7 Miniature Motors Encoder E9 3 Channel Optical Encoder Connector Quikie II, Dupont or equivalent (on request) dimensions in mm mass: 6.2g E9 Characteristics at 22ºC Number of lines available, 44, 2, 5 ) typical ma Supply current max ma 2 stand-by µa 5 Output signal CMOS compatible Electrical phase shift between A and B degree 9 ± 2 Duty cycle % 5 ±. count frequency khz 2 Operating temperature range at 9% humidity ºC -4 to + 85 Code wheel moment of inertia -7 x kgm 2.2 Supply voltage cc 5 ± % Pin Out ersion GND cc dir. stand-by A A B B Z Z ersion 2 GND cc dir. stand-by up A down B pulse Z 3 BC 6 BS 6BL 22BS 22BM 22BL. Available on Motor Types 22N GST GST/GT 26N48 28L8 28LT2 28DT2 3GT 35NT32 L = length (mm) / Page # / /73 ) ask for a 2R motor type for use with the E9 in 5 lines; other number of lines on request ; other number of lines on request 2) E9 Encoder is available for P53, P532, P85 and P852 models. isit for product details. 3) Dimensions with brushless motors not given. isit for product details. Encoder Typical Encoder Output Signal Features 2 channel quadrature output and index pulse Small size Integrated direction of rotation detection Stand-by function with latched state of channels (to de-activate the stand-by mode, connect the pin 4 to the ±5) Complimentary outputs Up/down pulse signals (on request) CMOS compatible. to DC or +5 DC Single 5 DC supply ) The input stand-by has to be connected 257

8 HEDS 55/554 Optical Encoder 3 26,2 4, 8,3 dimensions in mm L2 L Pin Function. Mass 2. N.C Channel A 4. cc 5. Channel B Characteristics at 22ºC 55/554 Measured alues Standard number of lines 96 to 24 Supply voltage 5 ± % Supply current, typical value ma 7-57 Output signals 2 channels, square wave in quadrature 3 channels (with index) Electrical phase angle between channels 9 ± º Output current per channel ma >5, TTL compatible Frequency response khz Moment of inertia kgm 2.6 x -7 Operating temperature ºC -4 to Connections 5 pins HEDS 55/54 L L2 25GST GT NT2R NT2R On request HP encoder available on other motors. Encoder also available with line-driver HP encoders are available for mounting on shaft diameters of 2,3,4 and 5. For more information, please ask for the Hewlett-Packard data sheet

9 Miniature Motors MR2 Encoder Magnetoresistive Encoder Specification unit value tolerance Encoder specifications (cc = 5. / 22 C) Output: 2-3 channels, square wave in quadrature, optional reference, 4 to 52 pulses per revolution. All following resolution are available: 52, 5, 4, 256, 25, 2, 6, 28,, 8, 64, 5, 4, 32, 2, 6, 8 & 4. Supply voltage min / max 4.5 / 5.5 Min / Supply current nominal / max) ma 2 / 25 typical / Rise/fall time (CL=5pF) ns 6 / 6 Rise / Fall Output frequency MHz 2 / 25 Electrical phase shift 4.5 / 5.5 ± 45 Pulse width Channel A % 5 ± 5 Pulse width Channel B % 5 ± [ppr] rpm 3 Operating temperature -3 / 85 Min / max Motor Type Encoder additional length [mm] 8G / Gs 2G 3N 6N 6G 7N/S/ 22N/S/ 23GST 25GST/G 35NT Output signals: Output connector: Encoder fall time rise time Ch Ch 2. Motor + 2. cc 3. Channel A 4. Channel B 5. GND 6. Motor - 7. Channel Z Connector poles type Quickie II or equivalent DIN 465 A (UL E688) t = line = 36 electrical t2 t3 t2 / t = duty cycle t3 = shift phase 259

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11 DRIES AND ELECTRONICS EBL-H-5-3 Portescap electronics are especially designed to take full advantage of Portescap miniature motors. EBL-H

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13 Miniature Motors EBL-H The EBL-H5-3 is a small sized 4 quadrants speed controller for brushless DC motors (up to 5 Watts) with Hall Sensors Specification and connection Inputs Power J GND PWR Motor connection J6 PH-2-3 cc GND H H2 H3 Logic connection J2 GND DIR SPD FO ENA OE Te- / Te+ Other specifications Connection Mechanical data Ground power In Power Supply Motor winding oltage RMS current Peak current acceleration Peak current deceleration Hall sensor supply Hall sensor supply Hall sensor signal (Integrated pull up resistor of Kohm connected to internal 5) Ground logic voltage Direction Speed control, analog input or PWM Speed out Enable Not used External temperature sensor optional Switching current bridge frequency speed (2 poles) Min Speed (2 poles) speed (4 poles) Min Speed (4 poles) speed (8 poles) Min Speed (8 poles) speed control resolution Power bridge temperature protection Wire gage Weight Dimensions (L x W x H) unit A A A ma Sensor type KHz RPM RPM RPM RPM RPM RPM Steps C AWG g mm value 5.5 / TTL Signal à CCW 5 à CW KHZ / 5 min / max min TTL Signal, one period per pair pole revolution TTL Signal à Off PTC or NTC Thermistor 7 9, x 92 x 5 tolerance Min / Typ Typ typ Min Min Min Typ typ typ typ Drives order p/n: 396 for size 5, 6BH and 22BH motors order p/n: 397 for size 6, 9,, 5 and nuvodisc series motors Please contact us for any motor not listed above or for any custom request (PID settings, peak current limitation...) ROHS compliant 263

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