The **W2AC-AB4A-R/Q** is a high-precision electromagnetic transducer (buzzer) manufactured by **DB Products Limited**. These components are widely used in telecommunications, handheld devices, and consumer electronics where space is limited but high-quality sound is required. --- ### 1. General Specifications Below are the typical electronic characteristics for the W2AC series: | Parameter | Value/Specification | | :--- | :--- | | **Type** | Electromagnetic Transducer (Magnetic Buzzer) | | **Rated Voltage** | 3.0 V (Typical) | | **Operating Voltage** | 2.0 ~ 5.0 V | | **Rated Current** | Max 100 mA | | **Coil Resistance** | 12 ± 3 Ω | | **Sound Pressure Level (SPL)** | Min 85 dB (at 10cm) | | **Resonant Frequency** | 2,700 Hz | | **Operating Temperature** | -40°C to +85°C | --- ### 2. Key Features and Suffix Meanings The model number contains specific data about its construction and compliance: * **W2AC**: The base series identifier for high-performance surface mount (SMD) magnetic transducers. * **AB4A**: Refers to the physical dimensions and internal mechanical tuning. * **-R**: Indicates compliance with **RoHS** (Restriction of Hazardous Substances) standards. * **-Q**: Often indicates a **high-quality/automotive grade** qualification or specific packaging requirements (like Reel Tape for automated assembly). --- ### 3. Electronic Driving Circuit Unlike a "piezo buzzer" with a built-in oscillator, this is a **transducer**. It requires an external AC signal or square wave to produce sound. #### Typical Driving Schematic ```cpp // Logic for driving the part using a microcontroller void playTone(int frequency, int duration) { // Generates a square wave at the Resonant Frequency (2700Hz) tone(buzzerPin, frequency, duration); } ``` * **Coil Protection:** Because it is an inductive load, a flyback diode is recommended in the driving circuit to prevent voltage spikes from damaging the transistor or MCU. * **Transistor Switching:** Usually driven via an NPN transistor (e.g., MMBT2222) because the 100mA current draw is higher than most MCU GPIO pins can provide. --- ### 4. Physical Dimensions (Approximate) These units are designed for SMT (Surface Mount Technology) assembly: * **Mounting Type:** Surface Mount (SMD) * **Orientation:** Side-opening or Top-opening (Side-firing is common for this series to save vertical space).