AS5305 Integrated Hall IC for linear and off-axis rotary motion detection
Integrated Hall IC for
Linear and Off-Axis Rotary Motion Detection
General Description
The AS5305 is a single-chip IC with integrated Hall
elements for measuring linear or rotary motion using multipole magnetic strips or rings.
This allows the usage of the AS5305 in applications where
the Sensor IC cannot be mounted at the end of a rotating
device (e.g. at hollow shafts). Instead, the AS5305 is
mounted off-axis underneath a multi-pole magnetized ring
or strip and provides a quadrature incremental output with
40 pulses per period at speeds of up to 20m/sec.
Complete system-on-chip
High reliability due to non-contact sensing
Extended temperature range
Suitable for the use in harsh environments
Robust against external magnetic stray fields
Key Features
Using, for example, a 32pole-pair magnetic ring, the
AS5305 can provide a resolution of 1280 pulses/rev, which
is equivalent to 5120 positions/rev or 12,3bit. The
maximum speed at this configuration is 9375 rpm.
High speed, up to 20m/s
Down to 14µm resolution per position step
User programmable pole length
The default pole pair length is 4mm (2mm north pole / 2mm
south pole). However, the chip accepts a wide range of
multi-pole magnetic strips or rings with pole pair lengths
between 2.26 and 5.91mm and magnetic field strengths
down to 5mT. The pole pair length can be adjusted by
programming. A minimum pole pair length of 2,26mm
allows a resolution of 14,125µm per position step.
Single index pulse per revolution for absolute position
measurement using a second magnetic track
40 pulses per magnetic period.
Linear movement
magnetic strips
Circular off-axis movement measurement using multipole magnetic rings
4.5 to 5.5V operating voltage
Magnetic field strength indicator
In addition to the multi-pole high-resolution track, the
AS5305 can read a second multi-pole reference track that
generates a single or multiple reference index pulse per
revolution, for absolute position identification.
The AS5305 is available in a small 20-pin TSSOP package
and specified for an operating ambient temperature of
-40° to +125°C.
The AS5305 is ideal for high speed linear motion and offaxis rotation measurement in applications such as
electrical motors
rotation knobs
industrial drives
Figure 1: Two different configurations of AS5305 with single or
double track multipole ring magnet
Revision 1.4
Figure 2: AS5305 with magnetic multipole strip
for linear motion measurement
Page 1 of 2
AS5305 Integrated Hall IC for linear and off-axis rotary motion detection
Figure 3 AS5305 Block Diagram
austriamicrosystems AG
A 8141 Schloss Premstätten, Austria
+43 3136 500 0
+43 3136 525 01
Devices sold by austriamicrosystems are covered by the warranty and patent indemnification provisions appearing in its Term of
Sale. austriamicrosystems makes no warranty, express, statutory, implied, or by description regarding the information set forth
herein or regarding the freedom of the described devices from patent infringement. austriamicrosystems reserves the right to
change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is
necessary to check with austriamicrosystems for current information. This product is intended for use in normal commercial
Copyright © 2007 austriamicrosystems. 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. To the best of
its knowledge, austriamicrosystems asserts that the information contained in this publication is accurate and correct. However,
austriamicrosystems shall not be liable to recipient or any third party for any damages, including but not limited to personal
injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or consequential
damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No
obligation or liability to recipient or any third party shall arise or flow out of austriamicrosystems rendering of technical or other
Revision 1.4
Page 2 of 2