The part number **1-156-R** typically refers to a high-voltage, high-reliability **Silicon Rectifier Diode** manufactured by companies such as **Dean Technology (HVCA)**. These components are designed for specialized industrial and scientific applications requiring robust voltage handling. --- ### 1. Technical Specifications The following table highlights the general electrical characteristics for the 1-156-R series: | Parameter | Specification | | :--- | :--- | | **Component Type** | Standard Recovery Rectifier | | **Peak Inverse Voltage (PIV)** | 15,000 Volts (15kV) | | **Average Forward Current ($I_o$)** | 100 mA to 150 mA | | **Max Forward Voltage Drop ($V_f$)** | ~15V to 20V (at rated current) | | **Max Reverse Current ($I_r$)** | 1.0 $\mu$A (at 25°C) | | **Operating Temperature** | -55°C to +150°C | --- ### 2. Physical Characteristics * **Encapsulation:** These diodes are usually housed in a molded plastic cylindrical case or an axial-lead epoxy package. * **Dimensions:** They are significantly larger than standard signal diodes (like a 1N4148) to prevent electrical arcing across the body of the component. * **Polarity:** The cathode is typically marked with a colored band. --- ### 3. Key Applications Because of its high voltage rating (15kV), the 1-156-R is used in circuits where standard semiconductors would instantly fail: 1. **X-Ray Power Supplies:** Used in the rectification stage of high-voltage generators for medical and industrial imaging. 2. **Electrostatic Precipitators:** Used in air filtration systems to remove particles from exhaust gases. 3. **CRT Displays:** Found in older television or monitor high-voltage "flyback" circuits. 4. **Laser Power Supplies:** Providing the high DC voltage necessary to excite gas lasers. 5. **Voltage Multipliers:** Often used in "Cockcroft-Walton" generator stacks to step up voltages into the hundreds of thousands of volts. --- ### 4. Safety and Handling When working with the 1-156-R or similar high-voltage components, adhere to the following: * **Creepage and Clearance:** Ensure sufficient physical distance between the diode leads and other conductive paths to prevent "flashover" (arcing through the air). * **Potting:** In many designs, these diodes are submerged in dielectric oil or encapsulated in silicone potting compound to increase insulation. * **Discharge:** Always ensure high-voltage capacitors in the circuit are fully discharged before touching the component.