The part number **DM19DC102JO3-SA-R02** refers to a high-precision, high-reliability **Silver Mica Capacitor** manufactured by Cornell Dubilier (CDE) or a similar specialized manufacturer. Silver mica capacitors are renowned for their stability, high Q-factor (low loss), and tight tolerances, making them ideal for RF applications. --- ### 1. Technical Specifications Breakdown | Parameter | Specification | | :--- | :--- | | **Capacitance** | 1,000 pF (1 nF) | | **Tolerance** | ±5% (indicated by 'J') | | **Voltage Rating** | 300V DC | | **Dielectric Material** | Silver Mica | | **Case Type** | DM19 (Dipped Mica) | | **Operating Temperature** | -55°C to +125°C | | **Termination** | Radial Leads (Standard solderable) | --- ### 2. Part Number Decoder (Typical) While manufacturers vary slightly, the nomenclature usually breaks down as follows: * **DM19:** Refers to the physical case size and style (Standard Dipped Mica). * **DC:** Represents the voltage rating (typically 300V in this sequence). * **102:** The capacitance value in picofarads. The first two digits (10) are significant figures, and the third (2) is the multiplier (100). $10 \times 10^2 = 1,000$ pF. * **J:** Tolerance code ($J = \pm 5\%$). * **O3:** Operating temperature range or specific lead spacing configuration. * **SA-R02:** Specific packaging or compliance suffixes (e.g., RoHS compliance or specialized taping). --- ### 3. Key Characteristics & Applications Silver mica capacitors are "precision" components. Unlike ceramic capacitors, they do not suffer significantly from aging or voltage coefficients. #### Key Features: * **High Stability:** Very low drift over time and temperature. * **High Q-Factor:** Extremely low losses at radio frequencies (RF). * **Voltage Withstand:** Excellent dielectric strength compared to physical size. #### Common Applications: 1. **RF Oscillators:** Used to set frequency where stability is critical. 2. **Filter Networks:** High-order filters requiring precise capacitance values. 3. **Transmitters:** Coupling and decoupling in high-frequency power stages. 4. **Audio Equipment:** Sometimes used in high-end audio for its linear characteristics. --- ### 4. Comparison with Alternatives | Feature | Silver Mica (DM19) | Ceramic (C0G/NP0) | Film Capacitor | | :--- | :--- | :--- | :--- | | **Stability** | Excellent | Very Good | Moderate | | **RF Performance** | Superior | High | Low | | **Cost** | High | Low | Medium | | **Size** | Bulkier | Compact | Large |