Summarize several common operation skills:
- Try to place the decoupling and filtering capacitors around the corresponding components. The arrangement of decoupling capacitor and filtering capacitor is an important measure to improve the power quality of the circuit board and improve the anti-interference capability. In fact, the cabling, pin connections, and wiring of printed circuit boards may bring about a large inductance effect. The presence of Inductance may cause ripple and glitch on the power cord, setting a UF decoupling capacitor between the power supply and the ground can effectively filter out high-frequency ripple. If a patch capacitor is used on the circuit board, the patch capacitor can be placed close to the power pin of the component. For some power conversion chips, or power input, it is best to set up a 10uf or larger capacitor to further improve the power quality.
- Mark the first step when creating a component library.
- If the component size is inaccurate, print it at and compare it with the actual component.
- Import the network table generated with the schematic diagram. The flying line displayed on the PCB can greatly help layout and cabling.
- Do not use the X or Y keys to flip the component during component layout; otherwise, the component cannot be welded.
- One way to strip two-layer panels is: one side only follows the horizontal line and the other side only follows the vertical line.
- Do not add irrelevant overholes near the pad.
- In the design rule, the width and spacing of the line width are set.
Shortcut Key:
- E-S-C (CTRL + H) highlight a physical connection
- P-T interactiveWiring
- * Switch between layers. A pass hole can be automatically added during cabling.
- Tab to open the properties of the elements, passing holes, or lines attached to the mouse
- The M-D is dragging a line or through a hole while its two endpoints are moving at the same time
- M-M drag only one line or through hole
- M-E drag an endpoint
- Space can rotate the components 90 degrees and 45 degrees for the cabling.
- CTRL + M measurement size
- End refresh Screen
- Pageup/down zoom in and out
- CTRL + scroll wheel to zoom in, zoom out, and scale down to a certain extent. The size of is displayed on the screen, which can be directly compared with the actual components.
Supplement: Cangzhou YuCircuit BoardProcessing technology: Line 6 mil, Distance 6 mil, inner diameter 12mil, outer diameter 22mil Filter capacitor, decoupling capacitor, and bypass Capacitor The filter capacitor is used in the power supply rectification circuit to filter out AC components. Make the output DC smoother.
The decoupling capacitor is used in places that do not need to communicate with each other in the amplifier circuit to Eliminate Self-excitation and ensure stable operation of the amplifier.
When the bypass capacitor is connected with a resistor, it is connected to both ends of the resistor to make the AC signal pass smoothly. 1. Understanding of decoupling Capacitor Energy Storage 1) The decoupling capacitor is used to remove high-frequency interference, such as RF signal. The interference enters through electromagnetic radiation.
In fact, the capacitor near the chip also plays a role in energy storage, which is the second. You can regard the total power supply as Miyun Reservoir. Water is required for every household in our building,
At this time, the water is not directly from the reservoir, so the distance is too far,
When the water comes, we are thirsty.
The actual water is from the water tower on the top of the building. The water tower is actually a buffer. In the microscopic view, when a high-frequency device is working, its current is discontinuous and the frequency is very high,
There is a distance between the VCC device and the total power supply, even if the distance is not long, in the case of high frequency,
Impedance z = I * WL R, the inductance of the line will be greatly affected,
This will cause the device to be unable to be supplied in time when the current is needed.
The decoupling capacitor can make up for this deficiency.
This is one of the reasons why many circuit boards place small capacitors on the VCC pins of high-frequency devices. (A Decoupling capacitor is usually connected in parallel on the VCC pin, so that the AC component is grounded from this capacitor .) 2) the high-frequency switch noise generated by the active device during the switch will be transmitted along the power cord. The main function of decoupling capacitor is to provide A local DC power supply is provided to the active device to reduce the propagation of switching noise on the board and guide the noise to the ground. 2.Difference between bypass capacitor and decoupling Capacitor Decoupling: removes RF energy from high-frequency devices entering the distribution network during device switching. The decoupling capacitor can also provide localized DC for the device. |
