KY-038 Sound Sensor Module – Microphone Module for Arduino
KY-038 Sound Sensor Module – Analog & Digital Microphone Detector
The KY-038 is a sound detection sensor module with an electret condenser microphone and LM393 comparator, providing both analog and digital outputs, ideal for Arduino, ESP32, and Raspberry Pi sound-activated projects.
Key Specifications
| Sensor Type | Electret condenser microphone with amplifier |
| Comparator IC | LM393 dual differential comparator (for digital output) |
| Operating Voltage | 3.3V – 5V DC |
| Output | Analog (AO) voltage proportional to sound intensity; Digital (DO) TTL output (HIGH/LOW based on threshold) |
| Adjustable Sensitivity | On‑board potentiometer to set digital trigger threshold |
| Signal Indicator | Built‑in LED lights when sound exceeds threshold (for digital) |
| Dimensions | Approx. 40 mm × 20 mm × 15 mm |
| Weight | Approx. 5 g |
What You Can Build With This
- Clap Switch: Build a simple clap‑activated LED switch using Arduino Uno, sensor digital output, and a relay module.
- Noise Level Monitor: Create an IoT sound level meter with ESP32 sending analog data to Blynk cloud dashboard.
- Sound-Activated Alarm: Program a Raspberry Pi to send email alerts when sound threshold exceeded, using Python and GPIO.
- CBSE Class 12 Physics Project: Study the variation of sensor output with distance and sound intensity, using multimeter and function generator.
- B.Tech Final Year Project: Design a smart home noise classification system using KY-038 with Arduino and machine learning on edge (TinyML) to identify door knocks vs. ambient noise.
Compatibility
| Platform | Compatible | Connection | Library / Method |
|---|---|---|---|
| Arduino Uno R3 | Yes | Digital: D2, Analog: A0 | digitalRead() / analogRead() |
| Arduino Nano | Yes | Digital: D2, Analog: A0 | digitalRead() / analogRead() |
| Arduino Mega 2560 | Yes | Digital: 2, Analog: A0 | digitalRead() / analogRead() |
| ESP8266 NodeMCU | Yes with condition | Digital: any GPIO; Analog: A0 (voltage divider required for 5V output) | digitalRead() / analogRead(A0) |
| ESP32 Dev Board | Yes if powered with 3.3V | Digital: any GPIO; Analog: ADC pin (GPIO34–39) | digitalRead() / analogRead() |
| Raspberry Pi Pico | Yes (use 3.3V power) | Digital: GP15, Analog: ADC0 | digitalRead() / analogRead() (Arduino‑Pico core) |
| Raspberry Pi 4 / 5 | Yes (digital only) | Digital: GPIO17; Analog requires MCP3008 ADC | RPi.GPIO / spidev for external ADC |
Wiring and Interface Notes
Connect VCC to 3.3V or 5V, GND to ground. Digital output connects to a digital GPIO pin; analog output connects to an analog input pin (ADC). For boards with 3.3V logic, power the module with 3.3V to avoid level shifting on analog output.
Frequently Asked Questions
What is the difference between the DO and AO pins on KY-038?
The DO (digital output) provides a high/low signal based on the threshold set by the potentiometer, ideal for simple on/off sound detection. The AO (analog output) outputs a continuous voltage proportional to sound intensity, allowing you to measure sound levels precisely.
Can I use the KY-038 for voice recognition?
No, the KY-038 outputs only amplitude-based signals and cannot distinguish specific words or frequencies. For voice recognition, consider a dedicated MEMS microphone with I2S interface and a microcontroller with processing power.
Ask Soldr above what you can build with this — it knows every Compoden kit this part appears in.
Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items