The **ASX04004-R** is a high-quality, miniature surface-mount (SMT) speaker manufactured by **PUI Audio**. It is part of their "AS" series, designed for compact electronic devices that require clear audio output in a small footprint. --- ### ## Technical Specifications Below are the primary electrical and physical characteristics of the ASX04004-R: | Parameter | Specification | | :--- | :--- | | **Impedance** | 4 Ohms | | **Power Rating (Rated/Max)** | 0.5W / 0.8W | | **Sound Pressure Level (SPL)** | 84 ±3 dB @ 0.5W, 10cm | | **Frequency Range** | 500 Hz ~ 20,000 Hz | | **Resonant Frequency (Fs)** | 500 Hz ±20% | | **Mounting Type** | Surface Mount (SMT) | | **Dimensions** | 13mm x 13mm x 4mm | | **Weight** | ~1.5 Grams | --- ### ## Key Electronic Features * **SMT Design:** Unlike traditional speakers with wires or pins, this component is designed for automated pick-and-place assembly. It can withstand the high temperatures of **lead-free reflow soldering**. * **Acoustic Material:** It typically utilizes a high-grade **NdFeB (Neodymium)** magnet. Neodymium provides a strong magnetic field in a tiny size, allowing for high sensitivity and efficiency. * **Diaphragm:** Often constructed from Polyetherimide (PEI) or similar high-temperature plastics to ensure durability and moisture resistance. * **Polarity:** The component features specific solder pads marked for polarity (Positive/Negative) to ensure correct phase alignment in multi-speaker systems. --- ### ## Typical Applications Due to its 4-ohm impedance and small profile, it is commonly found in: 1. **Handheld Medical Devices:** For audible alerts and heart rate monitoring tones. 2. **IoT Sensors:** For feedback or alarm signals. 3. **Portable Consumer Electronics:** Such as GPS units, scanners, or smart wearables. 4. **Security Systems:** Compact keypads that require voice prompts. --- ### ## Design Considerations When integrating the ASX04004-R into a PCB layout, consider the following: * **Enclosure Design:** Since this is a "raw" driver, the sound quality and bass response depend heavily on the mechanical housing (back-cavity) designed around it. * **Amplifier Matching:** Ensure the audio amplifier can handle a 4-ohm load. Driving this speaker with an amplifier designed only for 8-ohm loads may cause overheating or distortion. * **Solder Profile:** Follow the manufacturer's recommended reflow profile to avoid damaging the internal voice coil or melting the diaphragm.