AS5311_07 Datasheet, PDF (1/29 Pages) ams AG – High Resolution Magnetic Linear Encoder

AS5311
High Resolution Magnetic Linear Encoder
1 General Description
The AS5311 is a contactless high resolution magnetic linear encoder
for accurate linear motion and off-axis rotary sensing with a
resolution down to <0.5µm. It is a system-on-chip, combining
integrated Hall elements, analog front end and digital signal
processing on a single chip, packaged in a small 20-pin TSSOP
package.
A multi-pole magnetic strip or ring with a pole length of 1.0mm is
required to sense the rotational or linear motion. The magnetic strip
is placed above the IC at a distance of typ. 0.3mm.
The absolute measurement provides instant indication of the magnet
position within one pole pair with a resolution of 488nm per step (12-
bit over 2.0mm). This digital data is available as a serial bit stream
and as a PWM signal.
Furthermore, an incremental output is available with a resolution of
1.95µm per step. An index pulse is generated once for every pole
pair (once per 2.0mm).The travelling speed in incremental mode is
up to 650mm/second.
An internal voltage regulator allows the AS5311 to operate at either
3.3 V or 5 V supplies. Depending on the application the AS5311
accepts multi-pole strip magnets as well as multi-pole ring magnets,
both radial and axial magnetized (see Figure 1 and Figure 3).
Figure 1. AS5311 Block Diagram
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:
- Serial interface and
- Pulse width modulated (PWM) output
Incremental output with Index
“Red-Yellow-Green” indicators monitor magnet placement over
the chip
3 Applications
Micro-Actuator feedback
Servo drive feedback
Robotics
Replacement of optical encoders
VDD5V
VDD3V3
LDO 3.3V
Sin
Linear Hall
Array
Cos
&
Frontend
Amplifier
AS5311
Ang
DSP
Mag
OTP
Register
Programming
Parameters
PWM
Interface
Absolute
Interface
(SSI)
Incremental
Interface
MagINCn
MagDECn
PWM
DO
CSn
CLK
A
B
Index
Prog
www.ams.com/AS5311
Revision 1.12
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