am256l RLS, am256l Datasheet
am256l
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am256l Summary of contents
Page 1
... V power supply Low power consumption typical. Extended operating temperature range (-40 °C to +125 °C) SMD package SSOP28 General description The AM256L is a compact solution for angular position sensing. The IC senses the angular position of a permanent magnet placed above the chip. The permanent magnet diametrically polarized and of cylindrical shape ...
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... Data sheet AM256LD01_03 th Issue 3, 14 January 2009 Index Pin description............................................................................................................................3 Absolute maximum ratings .........................................................................................................5 Operating range conditions ........................................................................................................5 Digital outputs ............................................................................................................................5 Digital inputs............................................................................................................................... CCW rotation of the magnet............................................................................................5 Binary synchronous serial output SSI.........................................................................................6 Binary parallel output..................................................................................................................7 Incremental output......................................................................................................................7 Sinusoidal analogue outputs ......................................................................................................8 Hysteresis ..................................................................................................................................9 Position delay .............................................................................................................................9 Nonlinearity ...
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... Power supply Output mode selection 28 Error Output for monitoring Each AM256L is factory optimized to achieve optimum performance. The information is * stored in PROM. ** Buffered analogue output mode must be factory set (special order). The output resolution is selectable for incremental outputs only. When SR input is low *** then resolution is 64 ppr (pulses per revolution) if high then resolution is 32 ppr ...
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... Pin 19 (CS digital input with an internal pull-down resistor. When high, all digital output pins from are set to high impedance mode. This function can be used when several AM256L devices are used in parallel mode. It does not affect the buffered sine cosine outputs. ...
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... High level input voltage Low level input voltage CW or CCW rotation of the magnet The arrow in Figure 3 shows clockwise (CW) rotation of the magnet. The picture is a top view of the magnet placed above the AM256L. CCW is counter clockwise rotation. © 2009 RLS d.o.o. Symbol Min. Max. ...
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... Clock low Monoflop time The controller interrogates the AM256L for its positional value by sending a pulse train to the Clock input. The Clock signal must always start from high. The first high/low transition (point 1) stores the current position data in a parallel/serial converter and the monoflop is triggered. With each transition of Clock signal (high/low or low/high) the monoflop is retriggered ...
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... Parallel output data is available in 8 bit binary code. To activate parallel output the PS pin must be set low. Output data can be latched while reading the data. For CW rotation of the magnet the output position is increasing possible to order an AM256L version with position increasing for CCW rotation of the magnet (special order). ...
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... Data sheet AM256LD01_03 th Issue 3, 14 January 2009 Sinusoidal analogue outputs Agnd is an internally generated reference voltage. Typical value for Agnd is 3 supply used as a zero level for the analogue signals and it is buffered. The internal serial impedance of the buffer for reference voltage is 60 Ω. ...
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... Nonlinearity is defined as the difference between the actual angular position of the magnet and the angular position output from the AM256L. Readings are compared at each output position change. Integral nonlinearity is the total position error of the AM256L output. Figure 9 (page 10) shows a typical error plot if the recommended magnet is carefully positioned. Figure 10 (page 10) shows the error plot if the magnet is on the limit of alignment tolerances ...
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... Data sheet AM256LD01_03 th Issue 3, 14 January 2009 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0 128 AM256 output position Fig. 9: Typical integral nonlinearity plot with good magnet setup 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0 128 AM256 output position Fig. 11: Typical differential nonlinearity plot Parameter Max. integral nonlinearity Max. differential nonlinearity Max ...
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... To select a suitable magnet it is important to know the properties of the sensors. Hall sensors are only sensitive to the perpendicular component of the magnetic flux density (B). The AM256L has a Hall sensor array arranged in a circle with a radius of 1.5 mm. Sensors are located on the surface of the silicon. ...
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... The magnet can be placed below or above the device. The typical distance between the magnet and the sensors must be 1.6 mm for the recommended magnet Fig. 15: Cross section of the AM256L with dimensions Parameter Distance sensors – PCB plane Distance sensors – chip surface Distance sensors – ...
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... The offset represents a mean value of B measured at 1.6 mm distance from the magnet surface and at 1.5 mm radius. Offset will cause larger than normal integral nonlinearity errors if the AM256L placement is not in the center of the magnet rotation. Figure 18 shows the additional integral nonlinearity error caused by misalignment of the AM256L for ideal and recommended magnets ...
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... January 2009 Error signal Error signal can be used for alignment of the AM256L. The error signal is sinusoidal in shape with one period per turn. The amplitude of the error signal is proportional to the AM256L displacement. To achieve optimum setup the amplitude of the error signal should be minimized. ...
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... Data sheet AM256LD01_03 th Issue 3, 14 January 2009 Typical applications +5V +5V 10µF 3 Ihal Vdd D7/Data D6 Chip Select 19 CS D5/CB Data Latch D4/SB AM256 18 DL/SR D3/A 2 Sin D2/Ri 1 Cos D1/B D0 Agndi Iboh Vss 24 4 10nF 10nF 100nF Fig. 21: Parallel output +5V +5V 10µF 3 Ihal Vdd 9 D7/Data Chip Select 19 CS ...
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... Data sheet AM256LD01_03 th Issue 3, 14 January 2009 Characteristics All characteristics are measured at recommended conditions unless otherwise stated. Recommended conditions: Parameter Ambient temperature Distance magnet-sensors Signal amplitude Power supply Resistor for Ihal setup Resistor for Iboh setup Magnet 1,2 1 0,8 0,6 0 Ω ] ...
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... Data sheet AM256LD01_03 th Issue 3, 14 January 2009 0,8 0,7 0,6 0,5 0,4 0,3 0,2 0 Temperature [°C] Fig. 29: Signal amplitude as a function of temperature SSOP28 package dimensions Dimensions: Symbol Min. Typ. Max 0.05 A2 1.65 1.75 1.85 b 0.22 0.38 c 0.09 0.25 D 9.9 10.2 10.5 E 7.4 7.8 8 5.3 5 0.55 0.75 0.95 © 2009 RLS d.o. 100 150 Unit ...
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... NOTE: magnet must be ordered separately! The Angular Magnetic Encoder IC part number does not include a magnet. 2. Magnet Part Number RMM44A2C00 © 2009 RLS d.o.o. Description AM256L Angular Magnetic Encoder IC with default functionality Outputs: - Parallel - SSI - Incremental - Unbuffered Sine/Cosine SSOP28 plastic package Delivered in tubes (48 units per tube) ...
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... Data sheet AM256LD01_03 th Issue 3, 14 January 2009 Head office RLS merilna tehnika d.o.o. Cesta II. grupe odredov 25 SI-1261 Ljubljana - Dobrunje T +386 1 5272100 F +386 1 5272129 E mail@rls.si www.rls.si Document issues Issue Date Changes 02 8. 11. 2007 Changed layout Page 1: Changed the RLS colour to bright yellow Page 19: Corrected the contact information 03 14 ...