The **SP-236-R** is a high-performance, surface-mount (SMD) audio transducer (speaker) commonly used in telecommunications, medical devices, and portable electronics. It is manufactured by Soberton Inc. and is known for its compact profile and reliability. --- ### ## Technical Specifications Below is a breakdown of the primary electronic and physical characteristics of the SP-236-R: | Parameter | Value | | :--- | :--- | | **Rated Power** | 0.01 W (10 mW) | | **Maximum Power** | 0.02 W (20 mW) | | **Impedance** | 32 $\Omega$ ± 15% | | **Sound Pressure Level (SPL)** | 91 dB ± 3dB (at 0.1W / 0.1m) | | **Frequency Range** | 300 Hz – 3,400 Hz | | **Resonant Frequency** | 600 Hz ± 20% | | **Dimensions** | 23mm x 13mm | | **Mounting Type** | Surface Mount (SMD) / Reflow Solderable | --- ### ### Key Electronic Features 1. **Impedance Control:** At 32 Ohms, this speaker is designed for low-power circuits, making it compatible with standard microcontroller outputs or small audio amplifiers without requiring heavy current draw. 2. **Voice Coil Construction:** It utilizes a precision-wound voice coil that reacts to electromagnetic signals to move a Mylar diaphragm. 3. **Reflow Compatibility:** The "R" in the suffix often denotes that the part is designed to withstand the high temperatures of an automated SMT (Surface Mount Technology) reflow oven. 4. **Narrow Frequency Response:** The range (300Hz - 3.4kHz) is specifically optimized for **human speech**. This makes it ideal for voice prompts rather than high-fidelity music. --- ### ### Typical Application Circuit When integrating the SP-236-R into a PCB design, a simple Class-D amplifier or a transistor-driven circuit is typically used. ```cpp // Example: Driving a transducer with a PWM signal (Arduino-style) int speakerPin = 9; void setup() { pinMode(speakerPin, OUTPUT); } void loop() { tone(speakerPin, 1000); // Send 1kHz square wave to SP-236-R delay(500); noTone(speakerPin); delay(500); } ``` --- ### ### Usage Considerations * **Polarity:** Ensure the positive (+) and negative (-) terminals are oriented correctly on the PCB to maintain phase, especially if using multiple speakers. * **Enclosure:** Because this is a miniature speaker, its acoustic performance (especially bass) depends heavily on the "back-box" or housing volume provided by the device casing. * **Protection:** It is recommended to use a DC-blocking capacitor in series with the speaker to prevent voice coil overheating from DC offset.