The **AST-03008MR-R** is a specialized micro-speaker manufactured by **PUI Audio, Inc.** It belongs to their "AS" series of high-performance, compact speakers designed for space-constrained electronic devices. --- ### 1. Technical Specifications The table below highlights the core electronic and physical characteristics of the component: | Feature | Specification | | :--- | :--- | | **Transducer Type** | Dynamic (Moving Coil) | | **Impedance** | 8 Ohms (±15%) | | **Power Rating (Nominal)** | 0.3 Watts | | **Power Rating (Max)** | 0.5 Watts | | **Frequency Range** | 500 Hz ~ 10,000 Hz | | **Sound Pressure Level (SPL)** | 88 dB (±3dB) @ 0.1W/0.1m | | **Resonant Frequency (Fo)** | 850 Hz (±20%) | | **Mounting Type** | Surface Mount (Spring Contacts) | --- ### 2. Key Electronic Components & Materials * **Diaphragm:** Typically made of Mylar (PET) or a similar lightweight polymer to ensure high sensitivity and fast transient response. * **Magnet:** Utilizes a high-strength **NdFeB (Neodymium Iron Boron)** magnet. This allows for a high magnetic flux density in a very small footprint, which is critical for the 0.3W power handling. * **Voice Coil:** A precision-wound copper coil that reacts with the magnetic field to create sound. * **Contacts:** It features **Gold-plated spring contacts** (SMD style). This is a critical electronic feature as it allows for solderless integration onto a PCB, reducing manufacturing time and improving vibration resistance. --- ### 3. Application Use Cases Due to its small diameter (approximately 30mm) and thin profile, this part is used in: 1. **Handheld Devices:** Scanners, GPS units, and walkie-talkies. 2. **Medical Instrumentation:** Heart rate monitors or portable diagnostic tools for audible alerts. 3. **Industrial Controls:** Status beeps and voice prompts in control panels. 4. **IoT Devices:** Smart home sensors that require audio feedback. --- ### 4. Integration Considerations * **Enclosure Design:** Since this is a "raw" speaker driver, the acoustic performance (specifically bass response) depends heavily on the back-cavity design of the product's housing. * **Driving Circuit:** It can be driven by a standard Class-D audio amplifier or a simple transistor circuit if only PWM tones are required. * **Polarity:** The spring contacts are marked for polarity; ensuring correct phase is vital for sound quality when multiple speakers are used.