LM2904 Analog Decibel Detection Module Key benefits — why you need this module Fast, reliable soundlevel sensing for projects that respond to realworld noise. The module converts ambient sound into a stable analog signal so you can monitor and act on changing noise levels in real time. Reduces development time for noisetriggered systems. Built around the professional LM2904 chip, it delivers sensitivity and predictable behavior so you can focus on application logic instead of lowlevel signal conditioning. Easy to verify and troubleshoot. Dual LED indicators provide immediate visual feedback of detection and signal presence, speeding setup and field tuning. What it does and what makes it stand out Precision sensing: Uses the LM2904 operational amplifier to provide sensitivity decibel detection suitable for measurement and control tasks. Analog output for straightforward integration: Provides a 0–2.3V analog output proportional to sound intensity for direct connection to analog inputs or ADC channels. Visual feedback: Double LED indicators show detection status and signal activity for quick verification without tools. Designed for closedspace accuracy: Optimized to detect human voices and environmental noise reliably at distances up to 10 meters in indoor or enclosed environments. Stable transmission and integration: Engineered for stable analog output and easy incorporation into electronics or industrial setups. Compatibility, form and performance Output format: 0–2.3V analog signal compatible with standard analog inputs/ADCequipped controllers and dataacquisition systems. Core component: Professional LM2904 chip ensures consistent performance and predictable response characteristics. Module format: Compact PCBmounted sensing board with onboard indicators for quick deployment. Performance focus: sensitivity for voice and ambient noise detection, tuned for closed spaces and nearfield voice detection up to 10 meters. Who it's for Electronics engineers and system integrators building noiseaware devices. Hobbyists and makers developing soundactivated projects. Environmental researchers and workplace safety teams needing a simple analog decibel sensor for monitoring and logging. Practical use scenarios Smart home automation: Trigger lighting, ventilation, or notifications when voice or noise levels exceed a threshold in living spaces or rooms. Audio equipment calibration and testing: Monitor relative sound levels during equipment setup, tuning, or QA in a controlled indoor environment. Workplace or research monitoring: Implement noiselogging stations or simple alert systems in offices, classrooms, or labs to track voice and ambient sound trends. Quick integration notes Read the 0–2.3V analog output with any ADCequipped controller or data logger. Use the dual LEDs to confirm operation during setup. performance in closed or semienclosed spaces where voice detection up to 10 meters is required. Intended for users who need a compact, sensitivity decibel detection module based on the LM2904 chip for soundactivated and measurement applications.