The **KEPA-44PC-R** is a high-performance, shielded piezo electronic buzzer (transducer) designed for surface mounting (SMD). It is widely used in telecommunications, medical equipment, and consumer electronics where a high sound pressure level (SPL) and electromagnetic interference (EMI) protection are required. --- ### ## Technical Specifications The following table outlines the primary electronic and physical characteristics of the KEPA-44PC-R: | Parameter | Specification | | :--- | :--- | | **Transducer Type** | Piezoelectric | | **Operating Voltage** | 1.0 ~ 25.0 Vp-p | | **Rated Voltage** | 3.0 Vp-p (Square Wave) | | **Rated Current** | Max 3 mA | | **Sound Pressure Level (SPL)** | Min 80 dB at 10cm / 3Vp-p / 4kHz | | **Resonant Frequency** | 4,000 ± 500 Hz | | **Capacitance** | 12,000 pF ± 30% at 120Hz | | **Operating Temperature** | -30°C to +85°C | | **Mounting Type** | SMD (Surface Mount Device) | --- ### ### Key Electronic Components & Design #### 1. Piezoelectric Element At the core of the KEPA-44PC-R is a ceramic piezoelectric disc. When an oscillating voltage (AC or Square Wave) is applied, the ceramic material physically deforms (expands and contracts). This vibration moves the air, creating sound waves at the specified resonant frequency (4.0 kHz). #### 2. Shielded Housing (The "R" Suffix) The "R" in the part number typically denotes a specific revision or a **shielded** design. The housing is designed to: * **Minimize EMI:** Protect nearby sensitive radio-frequency (RF) circuits from the electrical noise generated by the piezo oscillation. * **Acoustic Chamber:** The internal plastic cavity is tuned to amplify the 4kHz frequency to reach the 80dB threshold efficiently. #### 3. SMD Terminals The part features gold-plated or tin-plated solder pads on the bottom. Because it is a surface-mount component, it is compatible with high-speed automated pick-and-place machines and reflow soldering processes. --- ### ### Drive Circuit Requirements Unlike an "indicator" (which makes sound just by applying DC), the KEPA-44PC-R is a **transducer**. It requires an external oscillating circuit to function. * **Input Signal:** A square wave is recommended for maximum volume. * **Impedance Matching:** Because the device is capacitive (12,000 pF), the driving circuit must be able to handle the reactive load without overheating the driver transistor or IC. ---