The **SP-2D-R** is a specific model of a **Miniature High-Voltage Power Supply** module, typically manufactured by companies like *Matsusada Precision*. These modules are designed to convert a low DC input voltage into a stable, high-precision high DC output voltage. --- ### 1. Key Technical Specifications The "SP" series generally denotes a proportional high-voltage DC-DC converter. Below are the estimated specifications for the SP-2D-R model: | Parameter | Typical Value | |:--- |:--- | | **Input Voltage** | 0 to +12V DC | | **Output Voltage** | 0 to -2000V DC (Negative polarity) | | **Output Current** | ~0.5 mA to 1.0 mA | | **Control Method** | Input Proportional | | **Mounting Type** | PCB Through-hole | | **Dimensions** | Approx. 25mm x 15mm x 15mm (Compact) | --- ### 2. Internal Electronic Architecture While the unit is encapsulated in epoxy for insulation, the internal circuitry consists of the following stages: #### A. Input Filtering - **Components:** SMD Capacitors and Inductors. - **Function:** Reduces electromagnetic interference (EMI) and stabilizes the input 12V line. #### B. Oscillator & Switching Circuit - **Components:** High-frequency Transistors/MOSFETs. - **Function:** Converts the DC input into a high-frequency AC signal (usually in the tens of kHz range) to allow for efficient transformation. #### C. Step-Up Transformer - **Components:** Ferrite core transformer with a high secondary-to-primary turn ratio. - **Function:** Increases the low-voltage AC to several hundred or thousand volts AC. #### D. Voltage Multiplier (Cockcroft-Walton Circuit) - **Components:** High-voltage Diodes and Ceramic Capacitors. - **Function:** Rectifies the AC back to DC while simultaneously "stacking" the voltage to reach the final -2000V output. --- ### 3. Pinout Configuration Most modules in this series utilize a standard 5-pin or 4-pin layout: 1. **+Vin:** Positive input power (0-12V). 2. **GND:** Common ground for input and output. 3. **Vout:** High Voltage Negative Output (-2kV). 4. **Case/Shield:** Connected to GND to reduce noise. --- ### 4. Common Applications Due to its small footprint and high stability, the SP-2D-R is used in: * **Photomultiplier Tubes (PMT):** Providing the necessary negative bias. * **Mass Spectrometry:** Ion source biasing. * **Electrostatic Chucks:** Small-scale electrostatic manipulation. * **Geiger-Müller Tubes:** Radiation detection biasing. --- ### 5. Safety Precautions * **Insulation:** Ensure PCB trace clearance (creepage) for -2000V to prevent arcing. * **Polarity:** The "R" in the model name often signifies **Reverse (Negative)** polarity. Ensure your load is compatible. * **Discharge:** Capacitors inside the module can hold a charge even after power is removed.