The **LSMT2-41041-R** is a high-performance, surface-mount (SMT) magnetic buzzer/transducer designed for audio signaling in compact electronic devices. It is widely used in automotive, industrial, and consumer electronics due to its small footprint and reliable sound output. --- ## Technical Specifications The following table outlines the primary electrical and physical characteristics of the LSMT2-41041-R: | Parameter | Specification | | :--- | :--- | | **Type** | Magnetic Transducer (External Drive) | | **Rated Voltage** | 3.0 Vp-p | | **Operating Voltage** | 2.0 ~ 4.0 Vp-p | | **Rated Current** | Max 100 mA | | **Sound Pressure Level (SPL)** | Min 87 dB at 10cm | | **Resonant Frequency** | 2,730 Hz | | **Coil Resistance** | 15 ± 3 Ω | | **Operating Temperature** | -40°C to +85°C | | **Mounting Type** | Surface Mount (SMD) | --- ## Key Components and Electronic Design ### 1. Magnetic Circuitry Unlike piezo buzzers that use crystals, the LSMT2-41041-R operates on **electromagnetism**. It consists of a permanent magnet, a copper wire coil, and a metal vibration disk (diaphragm). When an oscillating current passes through the coil, it generates a fluctuating magnetic field that moves the diaphragm to create sound waves. ### 2. External Drive Circuitry This part is a **transducer**, not a self-contained indicator. This means it **does not have internal oscillation circuitry**. * **Requirement:** You must provide a square wave signal at the resonant frequency (2,730 Hz) from an external MCU or timer (like a 555 timer). * **Driver Recommendation:** Because it can draw up to 100mA, it should not be driven directly by an MCU GPIO pin. A simple NPN transistor or MOSFET switching circuit is required. ### 3. Surface Mount Technology (SMT) The "LSMT" prefix indicates its package style. It is designed for automated pick-and-place assembly and is compatible with lead-free reflow soldering processes. --- ## Application Circuit Example To drive the LSMT2-41041-R safely, use a standard transistor buffer circuit: ```text VCC (3V) | [Buzzer +] [Buzzer -] | +----[ Collector ] [ NPN ]--[Base]--[ 1k Resistor ]--[ MCU PWM Pin ] [ Emitter ] | Ground ``` --- ## Use Cases * **Automotive:** Dashboard alerts, parking sensors, or indicator clicks. * **Medical:** Portable monitoring devices and alarm systems. * **Consumer:** Microwave beepers, smart locks, and handheld scanners.