1. Use good grounding method
Ensure that the design has adequate bypass capacitance and floor plan. When using an integrated circuit, be sure to use the appropriate decoupling capacitors near the power supply end to the ground (preferably the ground plane). The appropriate capacitance depends on the specific application, capacitance technology and operating frequency. The electromagnetic compatibility and susceptibility of the circuit can be optimized when the bypass capacitor is placed between the power and ground pins and close to the correct IC pins.
2. Allocation of virtual component packaging
Print a list of materials (bom) for inspection of virtual components. Virtual components have no associated encapsulation and are not transferred to the layout phase. Create a list of materials and then look at all the virtual components in the design. The only entries should be the power and ground signals, as they are considered virtual components that are processed exclusively in the schematic environment and not transmitted to the layout. Components displayed in the virtual portion should be replaced with components that have encapsulation, except for simulation purposes.
3. Make sure you have complete material list data
Check the material list report for sufficient complete data. After a material list report is created, it is carefully checked to complete any incomplete component, supplier, or manufacturer information in the component entry.
4. Sort according to component label
To facilitate sorting and viewing of material lists, ensure that component labels are serially numbered.
5, check the excess gate circuit
In general, all redundant gate inputs should have signal connections to avoid dangling inputs. Make sure you check all redundant or missing gate circuits and that all unwired inputs are fully connected. In some cases, if the input is suspended, the whole system will not work properly. Take the double op amp, which is often used in design. If only one of the two amp IC components is used, it is recommended that either the other amp be used as well, or the input of the unused amp be grounded, and an appropriate unit gain (or other gain) feedback network be laid out to ensure that the entire component works properly.
In some cases, IC with dangling pins may not work within the index range. Usually only when the IC device or other gates in the same device are not operating in a saturated state — the input or output is close to or on the component’s power supply rail, can the IC meet the index requirements when operating. This is often not captured by simulations, because simulation models typically do not connect multiple parts of an IC together to model the effect of dangling connections.
6. Consider the selection of component packaging
During the schematic drawing phase, component packaging and pad pattern decisions that need to be made during the layout phase should be considered. The following are some Suggestions to consider when selecting components according to their package.
Remember that the package includes the electrical bonding and mechanical dimensions (x, y, and z) of the component, the form of the component body, and the pins that connect the PCB. When selecting components, consider any installation or packaging constraints that may exist at the top and bottom of the final PCB. Some components (such as polar capacitors) may have a high headroom limit and need to be considered in the selection process. At the beginning of the design, you can draw a basic outline of the circuit board and then place some large or location-critical components (such as connectors) that you plan to use. In this way, the virtual perspective of the circuit board (without wiring) can be seen visually and quickly, and the relative positioning and component height of the circuit board and components can be given with relative accuracy. This will help ensure that PCB components fit properly into the outer package (plastic, case, frame, etc.) after assembly. 3 d preview mode can be called from the tools menu to browse the whole circuit board.
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