The **ME28XBA-R** is an infrared (IR) receiver module commonly used in remote control systems. It is designed to receive modulated IR signals (typically from a handheld remote) and convert them into electrical pulses that a microcontroller (like Arduino or ESP32) can interpret. Below is a detailed breakdown of its electronic specifications and features. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Carrier Frequency** | 38 kHz (Standard for most IR remotes) | | **Operating Voltage (Vcc)** | 2.7V to 5.5V DC | | **Supply Current** | ~0.4mA to 1.5mA (Low power consumption) | | **Reception Distance** | Up to 15–18 meters (depending on environment) | | **Output Type** | Active Low (Logic 0 when signal is detected) | | **Viewing Angle** | ±45 Degrees | --- ### 2. Pin Configuration The module typically features three pins. Looking at the front of the sensor (the side with the "lens" or bump), the pinout is generally as follows: 1. **OUT (Signal):** Outputs the demodulated pulse to the microcontroller. 2. **GND (Ground):** Connects to the negative terminal of the power supply. 3. **Vcc (Power):** Connects to the positive terminal (3.3V or 5V). --- ### 3. Internal Components and Functionality The ME28XBA-R is an integrated circuit that combines several electronic components into a single package: * **Photodiode:** Detects incoming infrared light. * **Automatic Gain Control (AGC):** Adjusts sensitivity based on ambient light noise to prevent false triggering. * **Band Pass Filter:** Specifically tuned to **38 kHz** to ignore IR light from sources like the sun or lightbulbs. * **Demodulator:** Strips away the 38 kHz carrier wave, leaving only the data signal. --- ### 4. Application Circuit Example To ensure stable performance, it is recommended to use a simple RC filter to clean the power supply. ```cpp // Basic Arduino Logic for IR Reception #include const int RECV_PIN = 7; // Connect OUT pin to Digital Pin 7 IRrecv irrecv(RECV_PIN); decode_results results; void setup() { Serial.begin(9600); irrecv.enableIRIn(); // Start the receiver } void loop() { if (irrecv.decode(&results)) { Serial.println(results.value, HEX); // Print received code irrecv.resume(); // Receive the next value } } ``` --- ### 5. Summary of Features * **High Immunity:** Excellent resistance to ambient light and electromagnetic interference. * **TTL/CMOS Compatibility:** The output signal levels match standard digital logic. * **Integrated Design:** No external components (like capacitors or resistors) are strictly required for basic operation, though they are recommended for noise reduction.