The **MHR24TCJ-R** is a high-performance, ultra-compact magnetic rotary encoder module, typically manufactured by **Magnesensor Technology (MST)**. It is widely used in high-speed brushless DC motor (BLDC) control and robotics. --- ## 1. Technical Specifications Below are the primary electronic and physical parameters for the MHR24TCJ-R: | Parameter | Specification | | :--- | :--- | | **Supply Voltage (Vcc)** | 3.3V to 5.0V DC | | **Resolution** | 12-bit (4096 positions per revolution) | | **Output Interface** | ABZ Phase (Incremental) + UVW (Commutation) | | **Maximum Rotation Speed** | Up to 30,000 RPM | | **Operating Temperature** | -40°C to +125°C | | **Sensor Type** | Hall-effect based Magnetic Sensor | --- ## 2. Key Electronic Components & Functions The module operates by detecting the magnetic field of a diametrically magnetized disc attached to the motor shaft. ### A. Integrated Circuit (ASIC) The core is a highly integrated **Hall-effect sensor IC**. It contains: * **Hall Element Array:** Measures the orthogonal components of the magnetic field. * **ADC (Analog to Digital Converter):** Converts raw magnetic signals into digital data. * **CORDIC Processor:** A DSP block that calculates the exact angle ($\theta$) in real-time. ### B. Output Signals 1. **Incremental (A/B Phase):** Two square waves shifted by 90° used to determine speed and direction. 2. **Index (Z Phase):** A single pulse per revolution indicating the zero-point reference. 3. **Commutation (U/V/W):** Simulates Hall-effect switch outputs, essential for driving BLDC motors without needing separate Hall sensors inside the motor. --- ## 3. Pinout Configuration (Standard) *While you should always verify with the specific datasheet revision, the standard connection logic is as follows:* | Pin Number | Signal | Description | | :--- | :--- | :--- | | 1 | VCC | Power Supply (3.3V / 5V) | | 2 | GND | Ground | | 3 | A | Incremental Phase A | | 4 | B | Incremental Phase B | | 5 | Z | Index / Zero Pulse | | 6-8 | U, V, W | Commutation signals for BLDC | --- ## 4. Implementation Code (Example) To read the A/B signals from the MHR24TCJ-R using an Arduino-based system, you can use an interrupt-driven approach: ```cpp const int pinA = 2; // Connect to Encoder A const int pinB = 3; // Connect to Encoder B volatile long position = 0; void setup() { pinMode(pinA, INPUT_PULLUP); pinMode(pinB, INPUT_PULLUP); attachInterrupt(digitalPinToInterrupt(pinA), updateEncoder, RISING); Serial.begin(9600); } void loop() { Serial.println(position); } void updateEncoder() { if (digitalRead(pinB) == HIGH) { position++; } else { position--; } } ``` ---