1. Firstly, the original type of chip capacitor and electrolytic capacitor are mainly used.
2. The capacitance deviation of the general solution capacitor is larger, which will not seriously affect the normal operation of the circuit. Therefore, it is possible to take a capacitor with a slightly larger or slightly smaller capacitance. However, in the frequency division circuit, the S correction circuit, the oscillation circuit and the delay circuit, the capacitance should be as consistent as possible with the calculation requirements. In some filter networks, the capacity of the chip capacitor and the electrolytic capacitor are also very accurate, and the error should be less than ±0.3% to 0.5%.
3. The withstand voltage must meet the requirements, and the selected withstand voltage should be equal to or greater than the original value.
4. Non-polarity capacitors are usually replaced by non-polar capacitors. In fact, there is no way to replace the two capacitors with twice the capacity of the capacitors in reverse series. The method is to use two polar chip capacitors and the positive electrode of the electrolytic capacitor. Connect or connect their two negative terminals.
5. When selecting chip capacitors and electrolytic capacitors, it is best to use high temperature resistant chip capacitors and electrolytic capacitors. The maximum operating temperature of high temperature resistant capacitors is 105 °C. When working under the highest operating temperature, it can guarantee 2000. Normal working hours around an hour. When using a 85 ° C capacitor at 50 ° C, its life can reach 22,000 hours, if you use high temperature chip capacitors and electrolytic capacitors at this time, its life can reach 90,000 hours.