MAE3 Features
- Quick, simple assembly, and disassembly
- -40C to +125C operating temperature
- 10-bit PWM output - 1,024 positions per revolution, 1 kHz
- Accepts +/- .025 in. axial shaft play
- Mounts to 0.750 in., 1.280 in. and 1.812 in. bolt circles
- Fits shaft diameters from .125 in. to .250 in. or 3mm to 6mm
- 10-bit Analog output - 2.6 kHz sampling rate
- 12-bit PWM output - 4,096 positions per revolution, 250 Hz
MAE3 Product Description
The MAE3 is an absolute magnetic kit encoder that provides shaft position information over 360° of rotation with no stops or gaps. This magnetic encoder is designed to easily mount to, and dismount from, an existing shaft to provide digital feedback information. The MAE3 is available with an analog or a pulse width modulated (PWM) digital output.
Analog output provides an analog voltage that is proportional to the absolute shaft position. Analog output is only available in 10-bit resolution.
PWM output provides a pulse width duty cycle that is proportional to the absolute shaft position. PWM output is available in 10-bit and 12-bit resolutions. While the accuracy is the same for both encoders, the 12-bit version provides a higher resolution.
The MAE3 consists of three components: base, push-on magnetic hub, and encoder body. The base will accommodate 0.750 in., 1.280 in., and 1.812 in. mounting bolt circles. No tools are needed for the push-on, collet gripping hub. The hub mounts to a standard shaft in seconds and provides a simple and reliable means of securing the magnet to the shaft.
Two 4-40 pan head screws secure the base and encoder body to any flat surface. If desired, the encoder can be powered up and rotated by hand to any desired absolute position before the screws are tightened.
Connecting to the MAE3 is simple. The 3-pin, high retention, snap-in 1.25mm pitch polarized connector provides for +5V, output, and ground.
Mechanical Drawings
Specifications
ENVIRONMENTAL
| PARAMETER | VALUE | UNITS |
|---|---|---|
| Operating Temperature | -40 to +125 | C |
| Vibration (5Hz to 2kHz) | 20 | G |
| Electrostatic Discharge, Human Body Model MIL-STD-883E, Method 3015.7 |
± 2 | kV |
MECHANICAL
| PARAMETER | VALUE | UNITS |
|---|---|---|
| Max. Shaft Axial Play | ±0.025 | in. |
| Max. Shaft Runout (1) | 0.004 T.I.R. | in. |
| Max. Acceleration | 250000 | rad/sec² |
| Max. Hub Moment of Inertia | 9.42 x 10^-7 | oz-in-s² |
| Mounting Screw Size | #4-40 x 1/4 | in. |
| 2 Screw Bolt Circle Diameter | 0.750 ± 0.005 | in. |
| 2 Screw Bolt Circle Diameter | 1.280 ± 0.005 | in. |
| 2 Screw Bolt Circle Diameter | 1.812 ± 0.005 | in. |
| Required Shaft Length, including axial play (1) Size 220 Shaft Length-option Size 500 Shaft Length-option |
0.220 (+0.015 / -0.020) 0.500 (+0.015 / -0.020) |
in. in. |
| Mounting Screw Torque | 4 - 6 | in-lbs |
| Technical Bulletin TB1001 - Shaft and Bore Tolerances | Download | |
(1) For optimum accuracy, the magnetic hub must be fully seated on the shaft and the shaft play must meet the specified axial and radial limits.
(2) The chip that decodes position uses sampled data. There will be fewer readings per revolution as the speed increases. The formula for the number of readings per revolution is given by:
10-bit PWM:
n = 625200 / rpm
12-bit PWM / Analog:
n = 156600 / rpm
ELECTRICAL
| PARAMETER | MIN. | TYP. | MAX. | UNITS |
|---|---|---|---|---|
| Power Supply | 4.5 | 5.0 | 5.5 | Volts |
| Supply Current | 16 | 20 | mA | |
| Power-up Time | 50 | mS |
ANALOG OUTPUT OPERATION
Analog output is only available in 10-bit resolution. The analog output voltage is ratiometric to the power supply voltage and will typically swing within 15 millivolts of the power supply rails with no output load. This non-linearity near the rails increases with increasing output loads. For this reason, the output load impedance should be ≥4.7kΩ and less than 100pF. The graphs below show the typical output levels for various output loads when powered by a 5V supply.
| PARAMETER | MIN. | TYP. | MAX. | UNITS |
|---|---|---|---|---|
| Position Sampling Rate | 2.35 | 2.61 | 2.87 | kHz |
| Propagation Delay | 384 | μS | ||
| Analog Output Voltage Maximum (1) | 4.987 | Volts | ||
| Analog Output Voltage Minimum (1) | 0.015 | Volts | ||
| Output Short Circuit Sink Current (2) | 32 | 50 | mA | |
| Output Short Circuit Source Current (2) | 36 | 66 | mA | |
| Output Noise (1-σ limit) | 0.046 | Deg. RMS |
(1) With no output load. See graphs below.
(2) Continuous short to +5V or ground will not damage the MAE3.
.
PWM OUTPUT OPERATION
The magnetic sensor chip in the MAE3 has an on-chip RC oscillator which is factory trimmed to 5% accuracy at room temperature (10% over full temperature range). This tolerance influences the sampling rate and the pulse period of the PWM output. If only the PWM pulse width ton and nominal pulse period are used to measure the angle, the resulting value also has this timing tolerance. However, this tolerance can be canceled by measuring both ton and toff and calculating the angle from the duty cycle.
| PARAMETER | MIN. | TYP. | MAX. | UNITS |
|---|---|---|---|---|
| PWM Frequency (-40C to 125C) 10-bit 12-bit |
0.877 220 |
0.975 244 |
1.072 268 |
kHz Hz |
| Minimum Pulse Width 10-bit 12-bit |
0.95 0.95 |
1.00 1.00 |
1.05 1.05 |
uS uS |
| Maximum Pulse Width 10-bit 12-bit |
974 3892 |
1025 4097 |
1076 4302 |
uS uS |
| Internal Sampling Rate 10-bit 12-bit |
9.38 2.35 |
10.42 2.61 |
11.46 2.87 |
kHz kHz |
| Propagation Delay 10-bit 12-bit |
48 384 |
uS uS |
||
| Output Transition Noise, 12-bit version (1) | .03 | Deg. RMS | ||
| Output Transition Noise, 10-bit version (1) | .12 | Deg. RMS | ||
| Output High Voltage (VOH: @4mA Source) (2) | Vcc -0.5 | V | ||
| Output Low Voltage (VOL: @4mA Sink) (2) | 0.4 | V |
(1) Transition noise is the jitter in the transition between two adjacent position steps.
(2) Continuous short to +5V or ground will not damage the MAE3.
10-bit PWM:
x = ((t on * 1026) / (t on+ t off)) -1
If x <= 1022, then Position = x
If x = 1024 then Position = 1023
12-bit PWM:
x = ((t on * 4098) / (t on+ t off)) -1
If x <= 4094, then Position = x
If x = 4096 then Position = 4095
PIN-OUTS
ANALOG OUTPUT (MAE3-A):
| PIN | NAME | DESCRIPTION |
|---|---|---|
| 1 | 5 | +5VDC power |
| 2 | A | Analog output |
| 3 | G | Ground |
PWM OUTPUT (MAE3-P10, MAE3-P12):
| PIN | NAME | DESCRIPTION |
|---|---|---|
| 1 | 5 | +5VDC power |
| 2 | P | PWM output |
| 3 | G | Ground |
ACCESSORIES
SCREWS
| Part #: | SCREW-440-250-PH |
|---|---|
| Description: | 4-40 x 1/4" Pan head screw |
| Quantity Required for Mounting | 2 per encoder |
CABLES / CONNECTORS
3-PIN MICRO:
| PART # | DESCRIPTION |
|---|---|
| CON-MIC3 | Connector |
| CA-MIC3-W3-NC | Connector on one end with 3 wires |
| CA-MIC3-SH-NC | Connector on one end with shielded cable |
- Connector built into encoder: Molex# 53398-0371.
- Mating connector housing: Molex# 51021-0300.
- Mating connector individual crimp-on pins: Molex# 50079-8100.
- To install connector pins, a special crimp tool is needed: Molex# 50079.
Notes
- Cables and connectors are not included and must be ordered separately.
- US Digital® warrants its products against defects in materials and workmanship for two years. See complete warranty for details.
Configuration Options |
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| MAE3 | - | Output A10 (Analog 10-Bit) P10 (PWM 10-Bit) P12 (PWM 12-Bit) | - | Bore Size 118 (3.0mm) 125 (1/8") 157 (4.0mm) 188 (3/16") 197 (5.0mm) 236 (6.0mm) 250 (1/4") | - | Shaft Length 220 (.220") 500 (.500") | - | Bolt Circle 7 (0.750") 12 (1.280") 18 (1.812") | - | Packaging B (Encoders packaged in bulk.) 1 (Encoders packaged individually.) | |||||||||||||||||
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PLEASE NOTE: This chart is for informational use only. Certain product configuration combinations are not available. Visit the MAE3 product page for pricing and additional information. |
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