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M3K Miniature Magnetic Incremental Kit Encoder

M3k Webproduct 01 Product Photo

M3K Features

  • Available in incremental and incremental/absolute configurations
  • Push-on hub spring loaded collet design
  • Motor shaft length of 0.500 in. or 0.390 in.
  • Fits shaft diameters from 3mm to 0.250 in.
  • 1 to 8,192 cycles per revolution (CPR)
  • 4 to 32,768 pulses per revolution (PPR)
  • A/B/Index incremental output and 12-bit PWM output for absolute position
  • Latching connector
  • Single 4~16V supply
  • 5V logic level outputs

See more info below

Configure the M3K

M3K Product Description

Restriction of Hazardous Substances

The M3K miniature magnetic kit encoder is designed to provide shaft position feedback for high volume, restricted space applications. The M3K outputs A, B, and Index digital quadrature signals and optional pulse width modulated (PWM) absolute position. The PWM output provides a pulse width duty cycle that is proportional to the absolute shaft position.

The M3K features a push-on hub design that can easily mount from 3mm to 0.250 in. diameter shafts. The M3K consists of three components: base, push-on magnetic hub, and encoder body. Various base options accommodate different length shafts, including a 0.586 in. or 0.750 in. bolt circle. No tools are required to install the push-on, collet-gripping hub, making assembly very easy. The hub mounts to a standard shaft in seconds and provides a simple and reliable means of securing the magnet to the shaft. Two mounting screws are provided that secure the base and encoder body.

The M3K miniature magnetic encoder is connected using a Molex PicoClasp (#5013300600) 6-conductor, polarized, 1mm pitch latching connector. Mating cables and connectors (see the Cables/Connectors web page) are not included and are available separately.

Please Note: Due to the M3K's design, it is recommended for a one-time installation.

 

Product Specifications

ENVIRONMENTAL

PARAMETER VALUE UNITS
Operating Temperature -40 to 100 C
Electrostatic Discharge, IEC 61000-4-2 ±1 kV
Vibration (10Hz to 2kHz, sinusoidal) 20 G
Shock (6 milliseconds, half-sine) 75 G

MECHANICAL

PARAMETER VALUE UNITS
Shaft Length (1)
0.586" bolt circle (5-option)
0.750" bolt circle (7-option)		  
0.39 ± 0.035
0.5 ± 0.035		  
in.
Max. Shaft Axial Play ±0.010 in.
Max. Shaft Runout 0.004 T.I.R. in.
Max. Acceleration 250,000 rad/sec²
Max Hub Moment of Inertia 9.4 x 10-7 oz-in-s²
Bolt Circle Diameter Tolerance ±0.005 in.
Mounting Screw Size
0.586 bolt circle (5-option)
0.750" bolt circle (7-option)
Metric (M-option)
#3-48 x 3/16"
#4-40 x 3/16"
M2.5 x 5mm		  
Mounting Screw Torque
0.586" bolt circle (5-option)
0.750" bolt circle (7-option)
Metric (M-option)		  
2 to 3
4 to 6
2 to 3		  
in-lbs

(1) Including axial play.

Download Technical Bulletin TB1001 - Shaft and Bore Tolerances

ELECTRICAL

PARAMETER MIN. TYP. MAX. UNITS NOTES
Supply Voltage 4.0 5.0 16.5 V  
Supply Current   17   mA no load, 5V power
Low-level Output,
A/B/Index		  
0.02		 0.4 V IOL= 4mA
no load
High-level Output,
A/B/Index		 4.0
4.8		   V IOL= -4mA
no load
Low-level Output,
PWM		   0.5
0.2		   V IOL= 0.5mA
no load
High-level Output,
PWM		   2.5
4.9		   V IOL= -0.5mA
no load
Output Rise/Fall Time,
A/B/Index		   25   nS no load
Output Rise Time,
PWM		   1   µS no load
Output Fall Time,
PWM		   25   nS no load
12-bit PWM Frequency   2.0   kHz Values up to 3.125 kHz available on request. Contact tech support.
PWM Duty Cycle range for 360 deg rotation 5   95 %  
  • Typical values are specified at Vcc = 5.0V and 25C.
  • A/B/Index outputs remain at 5V logic levels for Vcc > 5.0V
  • PWM output is open-drain with 5k pullup to Vcc. The output is clamp limited to 6.5V Typ. for Vcc >5.0V
CPR Max RPM (1) Typical Count Jitter ± 2σ limits x4 quadrature decoding Typical Angle Jitter ± 2σ limits x4 quadrature decoding

1

18720

0 counts

0 deg.

2

18720

0

0

4

18720

0

0

8

18720

0

0

16

18720

0

0

32

18720

0

0

64

18720

0

0

128

18720

0

0

256

18720

0

0

512

14648

± 1

± 0.18

1024

7324

± 1.4

± 0.12

2048

3662

± 1.4

± 0.062

4096

1831

± 2.1

± 0.05

8192

915

± 3.3

± 0.04

(1) minimum of 50 position samples per revolution

TIMING CHARACTERISTICS

PARAMETER SYMBOL MIN. TYP. MAX. UNITS
Symmetry X, Y   180   °e
Quadrature Z   90   °e
Index Pulse Width Po   90   °e
Ch. I Rise After Ch. B or Ch. A Fall t1   10   ns
Ch. I Fall After Ch. B or Ch. A Rise t2   10  

ns

TIMING DIAGRAM

CPR
The number of Cycles (C) of the A or B outputs Per Revolution.
Index (I)
The index output goes high once per revolution, coincident with the low states of channels A and B, nominally 1/4 of one cycle (90°e).
One Shaft Rotation
360 mechanical degrees.
One Electrical Degree (°e)
1/360th of one cycle.
One Cycle (C)
360 electrical degrees (°e). Each cycle can be decoded into 1, 2, or 4 states, referred to as x1, x2, or x4 resolution multiplication.
PPR
The number of resolvable Positions Per Revolution of the encoder disk with x4 quadrature decoding.
Quadrature (Z)
The phase lag or lead between channels A and B in electrical degrees, nominally 90°e.
Symmetry
A measure of the relationship between (X) and (Y) in electrical degrees, nominally 180°e.

PIN-OUTS

PIN DESCRIPTION
1 Ground
2 Index
3 B channel
4 +4~16.5VDC power
5 A channel
6 PWM

INCLUDED ACCESSORIES

1. CENTERING TOOL*

Part #: CTOOL - M3K - (Shaft Diameter)
Description: This reusable tool is used to accurately center the M3K base on the shaft.

2. SCREWS

Part #: SCREW-348-188-PH
Description: Pan Head, Philips #3-48 UNC x 3/16"
Use: Base Mounting
Quantity Required: 2
Screws are included
Part #: SCREW-440-118-PH
Description: Pan Head, Philips #4-40 UNC x 3/16"
Use: Base Mounting
Quantity Required: 2
Screws are included
Part #: SCREW-M25-5MM-PH
Description: Pan Head, Philips, M2.5 x 0.45 x 5MM
Use: Base Mounting
Quantity Required: 2
Screws are included

Additional Information

Product Notes

  • US Digital® warrants its products against defects in materials and workmanship for two years. See complete warranty for details.

Datasheets

Assembly Instructions

Press Releases

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