Here are some tips from Professional Electronic Device Design Secrets that are helpful for actual electronic product design:
Design planning and requirements understanding
Clear requirements: Before starting the design, it is important to fully understand the product's functions, performance, cost, size, use environment and other requirements to avoid design errors due to misunderstanding of requirements. This is the basis for ensuring the success of the design.
Drawing a block diagram: Create a block diagram at the beginning of the design, presenting the entire electronic design schematic in the form of multiple modules and their interrelationships, which helps to plan the design process and set goals in advance, and also facilitates team members to understand the design ideas, laying the foundation for subsequent detailed design.
Circuit design and layout
Reasonable division of functional units: Decompose the entire circuit into several functional units that can be modified and operated independently, so that different teams or individuals can design and develop separately, improve work efficiency, and facilitate subsequent debugging and troubleshooting.
Optimize power and ground layout: Good power and ground layout can reduce interference and noise, and improve circuit stability and reliability. For example, when using multi-layer board design, arrange the power layer and ground layer reasonably to make the return path of power and ground shortest and the impedance lowest.
Differential symmetry and matching: In high-speed signal transmission, matching the length and impedance of differential signal lines can minimize signal distortion and crosstalk, improve system stability and performance, and is often used in the design of high-speed data transmission interfaces, radio frequency circuits, etc.
Use zero-ohm resistors: Zero-ohm resistors can be used to optimize circuit board wiring as a bridge between different configurations or functional modules, which is convenient for circuit modification and debugging after the circuit board is completed, and can also isolate problem areas during troubleshooting.
Routing and signal integrity
Follow routing rules: ensure sufficient spacing between routings to reduce crosstalk; select appropriate routing widths based on current and signal speed to reduce line impedance and signal loss; try to use 45-degree or 90-degree routing angles and avoid sharp angles to reduce signal reflection and loss.
Consider signal integrity: pay close attention to the signal transmission path during the design process to avoid signal distortion, delay, crosstalk and other problems. For example, for high-speed signals, strict timing analysis and simulation are required to ensure the integrity of the signal during transmission.
Electromagnetic compatibility design
Use shielding technology: shield sensitive components or circuit parts that are susceptible to interference with shielding covers, shielding wires, etc. to reduce the impact of external electromagnetic interference, and also prevent the electromagnetic radiation generated by itself from interfering with other devices.
Filtering design: Reasonably use filters on power lines and signal lines, such as LC filters and π-type filters composed of capacitors and inductors, to effectively filter out noise in the power supply and interference signals on the signal line, and improve electromagnetic compatibility.
Reasonable grounding planning: Use single-point grounding, multi-point grounding or mixed grounding to ensure good grounding effect, provide a low-impedance discharge path for electromagnetic interference, and reduce interference caused by ground potential differences.
Testing and verification
Make prototypes and test: Make test prototypes as early as possible in the design process, and verify whether the functions and performance of the design meet expectations through actual tests. Give the prototype to customers or relevant personnel for trial use and collect feedback so as to find problems and make improvements in time, so as to avoid problems that are found after mass production and lead to a significant increase in costs.
Detailed records and documentation: record every step in the design process, every modification and its reasons, as well as detailed information such as test results. These documents not only help to trace back design ideas and troubleshoot problems when needed later, but also facilitate communication and collaboration between team members and knowledge inheritance.
Design optimization and cost control
Consider manufacturability: When designing, it is necessary to consider the manufacturing process and cost of the product, select appropriate components and materials, optimize the circuit layout and structure, make it easy to manufacture, reduce production costs and production cycles, and improve production efficiency.
Resource reuse: When designing current electronic products, it is necessary to consider future reusability, make circuit modules, codes, etc. easy to copy and modify, so that they can be quickly applied in subsequent projects, and reduce the time and cost of repeated development.