The **08MS-2-R** is a specific electronic component typically identified as a **micro-miniature magnetic buzzer** (also known as an electromagnetic transducer). These are widely used in portable electronics where space is limited but audible feedback is required. --- ### 1. Technical Specifications Below is a breakdown of the typical electrical and physical characteristics for the 08MS series: | Parameter | Typical Value | | :--- | :--- | | **Type** | Magnetic / Electromagnetic | | **Rated Voltage** | 1.5V - 3.0V DC | | **Operating Voltage** | 1.0V ~ 5.0V DC | | **Rated Current** | Max 80mA (at rated voltage) | | **Sound Pressure Level (SPL)** | Min 80dB - 85dB at 10cm | | **Resonant Frequency** | 2700 Hz - 2730 Hz | | **Coil Resistance** | 12 $\Omega$ ± 3 $\Omega$ | | **Mounting Type** | Surface Mount (SMD) / Reflow Soldered | | **Dimensions** | ~ 8.5mm x 8.5mm x 4.0mm | --- ### 2. Core Components & Construction The "08MS" series usually consists of the following internal parts: * **Housing:** A heat-resistant plastic (usually LCP or PPS) designed to withstand high temperatures during reflow soldering. * **Magnet/Coil:** A copper wire coil wrapped around a core. When current passes through, it creates an electromagnetic field. * **Vibrating Diaphragm:** A thin metal plate that reacts to the magnetic field, moving up and down to create sound waves. * **Terminals:** Gold-plated or tin-plated pads (R-suffix often denotes RoHS compliance) for PCB connection. --- ### 3. Driving Circuitry Unlike "Active" buzzers, this component is usually a **Passive Transducer**. This means it requires an external oscillating signal (PWM) to produce sound. **Typical Drive Circuit:** ```text [MCU Pin] ---- [Resistor] ---- [Base of NPN Transistor] | [Collector] ---- [08MS-2-R] ---- [VCC] | [Emitter] ---- [GND] ``` *Note: A flyback diode is often placed in parallel with the buzzer to protect the circuit from voltage spikes.* --- ### 4. Part Number Breakdown * **08:** Refers to the physical size (approximately 8.5mm). * **MS:** Designates "Magnetic Surface Mount." * **2:** Often indicates the voltage rating or specific generation/frequency. * **R:** Indicates **RoHS Compliant** (Lead-free) or **Tape & Reel** packaging for automated assembly. --- ### 5. Common Applications * **Handheld Devices:** Glucometers, pagers, and scanners. * **Consumer Electronics:** Microwave timers, white goods, and cameras. * **Automotive:** Dashboard alerts or proximity sensor beeps.