In front of two, followed by two, are generally a relatively large and then a small tiles. What is the role? What is the difference between before and after? For example, 7805 this figure!
Large capacity is low-frequency filtering, the capacity is small high-frequency filter.
Voltage regulator as much as possible to make the input voltage to 7805 DC voltage, 7805 output is also possible so that the output voltage is DC voltage.
Thank you for your question
Capacitor has a filtering effect, the capacitance value is large, filter out low frequency, small filter high frequency. The front two are the diodes rectified out of the corrugated DC, become more stable, remove the high frequency of clutter and low frequency fluctuations. The better DC power supply regulator block work. The output voltage of the regulator block has been relatively smooth, and the high-frequency harmonics are filtered out, and the low-frequency ripple is filtered out so that the output voltage is very smooth.
I looked at you this figure is a regulator circuit (positive), I learned this time, or in six years ago, and simple to analyze with you.
????Rectifier circuit came, we see a relatively large capacitor, generally have thousands of micro-hair, but also electrolytic capacitors (with positive and negative points of the points). The role of this capacitor, we like to say that the rectifier, it is also known as rectifier capacitor, so that the DC point is more smooth, as to how to make it smooth, this is the working principle of the capacitor (charge and discharge).
????Next, we can see, in the three-terminal regulator before and after a relatively small capacitor, but also the dielectric capacitor (no positive and negative points). His main role is to consider waves and protection. The most important thing is protection.
????The last capacitor, which is a point to solve the capacitor, the main role is to regulate the voltage, we also known as the output capacitor.
????Well, on the analysis so much, if you want to speak, the basic knowledge involved more. Learn electronics and electrical engineering, basic knowledge is really important, we must work on the components of the basic circuit, to be very familiar with, so as to make you in the future study do not feel difficult. Refueling
Large capacitor from the role of low-frequency filter, a small capacitor from the role of high-frequency filtering.
