as5311 austriamicrosystems, as5311 Datasheet
as5311
Available stocks
Related parts for as5311
as5311 Summary of contents
Page 1
... Figure 1 and Figure 3). Figure 1: AS5311 with multi-pole magnetic strip for linear motion sensing www.austriamicrosystems.com Preliminary Data Sheet The AS5311 is available in a Pb-free TSSOP-20 package and qualified for an ambient temperature range from -40°C to +125°C. 2 Key Features Two 12-bit digital absolute outputs : ...
Page 2
... AS5311 Data Sheet Figure 3: AS5311 with multi-pole ring magnets for off-axis rotary motion sensing 4 Pinout 4.1 Pin Assignments Figure 4: AS5311 pin configuration, TSSOP-20 4.2 Pin Description Pin 4(A), 5(B) and 7(Index) are the incremental outputs. The incremental output has a resolution of 10-bit per pole pair, resulting in a step length of 1.95µm. ...
Page 3
... AS5311 Data Sheet Pin 8 is the supply ground pin. Pins 18 and 19 are the positive supply pins. For 5V operation, connect the 5V supply to pin 19 and add a 2µ2…10µF buffer capacitor at pin 19. For 3.3V operation, connect both pins 18 and 19 to the 3.3V supply. Pin 9 is used for factory programming only. It should be connected to VSS. ...
Page 4
... AS5311 Data Sheet 5 Electrical Characteristics 5.1 Absolute Maximum Ratings Stresses beyond those listed under “Absolute Maximum Ratings“ may cause permanent damage to the device. These are stress ratings only. Functional operation of the device at these or any other conditions beyond those indicated under “Operating Conditions” is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
Page 5
... AS5311 Data Sheet 5.3 DC Characteristics for Digital Inputs and Outputs 5.3.1 CMOS Schmitt-Trigger Inputs: CLK, CSn (CSn = internal Pull-up) Operating conditions -40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5-5.5V (5V operation) unless amb otherwise noted. Parameter High level input voltage Low level input voltage Schmitt Trigger hysteresis ...
Page 6
... AS5311 Data Sheet 5.4 Magnetic Input Specification Operating conditions -40 to +125°C, VDD5V = 3.0-3.6V (3V operation) VDD5V = 4.5 - 5.5V (5V operation) unless amb otherwise noted. Two-pole cylindrical diametrically magnetised source: Parameter Symbol Pole length Lp Pole pair length t mag Magnetic input field B pk amplitude Magnetic offset B off Magnetic field ...
Page 7
... AS5311 Data Sheet Parameter Symbol Power-up time System propagation delay absolute output : System propagation delay incremental output Internal sampling rate for absolute output Hysteresis, incremental outputs Read-out frequency Integral Non-Linearity (INL) is the maximum deviation between actual position and indicated position. Differential Non-Linearity (DNL) is the maximum deviation of the step length from one position to the next. ...
Page 8
... A and B for every pole pair. The outputs A and B are phase shifted by 90 electrical degrees, which results in 1024 edges per pole pair. As the incremental outputs are also repeated with every pole pair, a constant train of pulses is generated as the magnet moves over the chip. Figure 5: AS5311 outputs relative to magnet position www.austriamicrosystems.com Revision 1.00 ...
Page 9
... AS5311 Data Sheet 6.1 Incremental Outputs Figure 6 shows the two-channel quadrature output of the AS5311. Output A leads output B when the magnet is moving from right to left and output B leads output A when the magnet is moving from left to right (see Figure 14). Figure 6: Incremental outputs Increm en tal outputs ...
Page 10
... AS5311 Data Sheet 6.2 Incremental Output Hysteresis Figure 7: Hysteresis illustration To avoid flickering incremental outputs at a stationary magnet position, a hysteresis is introduced. In case of a movement direction change, the incremental outputs have a hysteresis of 2 LSB. For constant movement directions, every magnet position change is indicated at the incremental outputs (see Figure 6). If for example the magnet moves from position „ ...
Page 11
... AS5311 Data Sheet A value of zero or close to zero indicates a missing magnet. Figure 9: Synchronous serial interface with magnetic field strength data If CSn changes to logic low, Data Out (DO) will change from high impedance (tri-state) to logic high and the read-out will be initiated. After a minimum time t CLK FE, Each subsequent rising CLK edge shifts out one bit of data ...
Page 12
... Z-axis Range Indication (“Red/Yellow/Green” Indicator) The AS5311 provides several options of detecting the magnet distance by indicating the strength of the magnetic field. Signal indicators MagINCn and MagDECn are available both as hardware pins (pins 1 and 2) and as status bits in the serial data stream (see Figure 8). Additionally the LIN status bit indicates the non- recommended “ ...
Page 13
... All other combinations 7 Pulse Width Modulation (PWM) Output The AS5311 provides a pulse width modulated output (PWM), whose duty cycle is proportional to the relative linear position of the magnet within one pole pair (2.0mm). This cycle repeats after every subsequent pole pair: t ⋅ ...
Page 14
... AS5311 Data Sheet 8 3. Operation The AS5311 operates either at 3.3V ±10 ±10%. This is made possible by an internal 3.3V Low- Dropout (LDO) Voltage regulator. The internal supply voltage is always taken from the output of the LDO, meaning that the internal blocks are always operating at 3.3V. ...
Page 15
... The lateral movement range (stroke) is limited by the area at which all Hall sensors of the IC are covered by the magnet in either direction. The Hall array on the AS5311 has a length of 2.0mm, hence the total stroke is maximum lateral Stroke = Length of active area – length of Hall array Note: active area in length is defined as the area containing poles with the specified 1 ...
Page 16
... AS5311 Data Sheet Figure 14: Alignment of magnet strip with AS5311 sensor IC position value increases rightmost magnet position Die C/L vertical airgap www.austriamicrosystems.com 3.0475±0.235 1. 1.00 3.0475±0.235 magnet strip carrier see text 1.00 ± 0.1 Revision 1.00 leftmost magnet position ...
Page 17
... The graph shows the accuracy over a stroke of 8mm at two different vertical gaps, 0.2mm and 0.4mm. As displayed, the accuracy is virtually identical (about +/- 10µm) for both airgaps due to the automatic gain control of the AS5311 which compensates for airgap changes. The accuracy depends greatly on the length and strength of each pole and hence from the precision of the tool used for magnetization as well as the homogeneity of the magnet material ...
Page 18
... AS5311 Data Sheet 11 AS5311 Off-axis Rotary Applications The AS5311 can also be used as an off-axis rotary encoder, as shown in Figure 3. In such applications, the multi-pole magnetic strip is replaced by a multi-pole magnetic ring. The ring can have radial or axial magnetization. Figure 16: Angular resolution and maximum speed versus ring diameter AS5311 off-axis rotary resolution & ...
Page 19
... AS5311 Data Sheet 12 Package Drawings and Marking 20 Lead Thin Shrink Small Outline Package – TSSOP20 Figure 17: AS5311 Package dimensions and Hall array location www.austriamicrosystems.com Revision 1. ...
Page 20
... Max 13 Ordering Information Delivery: Tape and Reel (1 reel = 2000 devices) Tubes (1 box = 100 tubes à 77 devices) Order # AS5311ASSU for delivery in tubes Order # AS5311ASST for delivery in tape and reel 14 Recommended PCB Footprint www.austriamicrosystems.com Marking: AYWWIZZ A: Pb-Free Identifier inch Y: Last Digit of Manufacturing Year ...
Page 21
... AS5311 Data Sheet 15 Copyrights Copyright © 2009, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria – Europe. Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. All products and companies mentioned are trademarks or registered trademarks of their respective companies. ...