Motor Solution Using a Magnetic Encoder

The motor solution using a magnetic encoder is a solution to control motor by combining the permanent magnet synchronous motor (brushless DC motor) and the magnetic encoder. This solution enables to easily evaluate motor control using a magnetic encoder by using sample software in combination with the motor solution kit. Also, can easily check the functions, settings, and software processing of MCU for acquiring position information from the magnetic encoder.

What is a magnetic encoder?

A magnetic encoder is a kind of position sensor used for motor control or a sensor that converts the change in the magnetic field into an electric signal to output. The magnetic encoder has two types, The one outputs position information as an analog signal and the other outputs it as a digital signal like encoder. The magnetic encoder which outputs the digital signal can detect an angle using the timer function of the MCU like optical encoder. The magnetic encoder which outputs the analog signal, on the other hand, obtains the output signal (sin, cos) of sensor with the AD mounted on MCU and angle information with arc tangent.

Magnetic encoder outputting digital

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Magnetic encoder outputting analog

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System configuration

Magnetic encoder outputting digital

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Magnetic encoder outputting analog

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Output signal correction by the magnetic encoder which outputs analog

The magnetic encoder which outputs the analog signal can obtain correct angle information by adjusting offset , gain (amplitude) and phase for the outputted analog signal. In this solution, these are automatically adjusted during startup, which enables to obtain correct angle information. If you use the magnetic encoder which outputs the digital signal, please refer to the sample software for vector control using encoder.

Offset・gain correction

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Phase correction

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In this solution, the operation has been confirmed using TMR magnetic encoder by TDK, TAD2141 (digital output) and TAS2143 (analog output).

System configuration & Solution menu list

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