There are four types of circuit board schematic diagrams: schematic, block diagram, assembly diagram, and printed circuit board diagram.
1. Schematic diagram, also called electrical schematic diagram.
Schematics directly reflect the structure and working principles of electronic circuits and are generally used for circuit design and analysis. When analyzing a circuit, you can learn how the circuit actually works by identifying the symbols of the various circuit elements drawn in the diagram and the connections between them. A schematic diagram is a tool that reflects the working of an electronic circuit.
2. Block diagram.
A block diagram is a circuit diagram that uses block diagrams and connections to represent the working principle and composition of a circuit. Basically, this is also a schematic diagram, but in this diagram there are almost no symbols except boxes and wires. The main difference between the above schematic and a schematic diagram is that all components of the circuit and how to connect them are drawn in great detail. A schematic simply divides the circuit into functional parts, describes each part as a box, gives the box a simple description, and uses connecting lines (sometimes arrows) between modules. relationships between boxes. Therefore, the block diagram can only reflect the general working principle of the circuit.
3. Assembly drawing.
This is the circuit assembly diagram. The symbols on the diagrams are usually physical outlines of circuit components. We just need to follow the drawings and connect some circuit components to assemble the circuit. This circuit diagram is usually used by beginners. The assembly drawings vary depending on the assembly template.
The main purpose of electronic products is the printed circuit board (PCB) introduced below, so the printed circuit board is the main form of assembly drawing. When we first started learning electronic knowledge, in order to get in touch with electronic technology earlier, we chose a threaded plate as the basic installation template, so the installation diagram became another model.
4. Circuit board diagram.
The full name of circuit board diagram is printed circuit board diagram. It belongs to the same circuit diagram as the assembly diagram and is used for the assembly of the actual circuit.
A printed circuit board is an insulating board covered with a layer of metal foil. Then the circuit does not need to corrode the metal foil. The circuit components are connected between the remaining metal foil, which is then used to mount the circuit components on the insulating board.
connections between boards. Printed circuit boards are also called "copper boards" because they are plated with copper on one or both sides. The distribution of components on a printed circuit board is often very different from that on a schematic diagram.
This is mainly because in the design of printed circuit boards, the main consideration is the distribution and connection of components, and factors such as component volume, heat dissipation, anti-interference, and anti-coupling need to be considered.
A printed circuit board designed with these factors in mind will be difficult to visually match the schematic. In fact, it performs the circuit function better.
With the development of technology, the production technology of printed circuit boards (PCB) has made great progress. In addition to single and double panels, there are many panels widely used in daily life, industrial production, aerospace and other fields.
Among the above four key points of circuit diagrams, the circuit schematic diagram is the most common and important. The schematic diagram is easy to understand, and you can basically understand the circuit principles and draw block diagrams, design assembly drawings and printed circuit board diagrams. It is also very convenient to master electrical schematics, maintain and design electrical equipment.
Therefore, the key is to master the schematic.
The schematic diagram mainly consists of four parts: component symbols, connections, nodes, and comments. The component symbol represents the component in the actual circuit, and its shape is not necessarily similar to the actual component, or even completely different. But it generally shows the characteristics of the component, and the number of pins is consistent with the actual component. The connection represents the wire in the actual circuit. Although it is a wire in the schematic diagram, in commonly used printed circuit boards, it is often not a wire but a copper foil block of various shapes, just like many in the radio schematic diagram. The connections in the printed circuit board diagram are not necessarily linear, they can also be copper films of a certain shape. Nodes represent the connection relationships between several component pins or several wires. All component pins and wires connected to the node, regardless of the number, are conductive. Annotations are very important in schematic diagrams. All text in schematic diagrams can be classified into the annotation category. If you look closely at the above pictures, you will find that there are annotations in various places on the schematic diagram. They are used to explain the model, name, etc. of the components.
Circuit board schematic design software
PROTEL is a classic schematic design software. Of course, others include Protel DXP, Pads, Pcad, Orcad, powerlogic, allegro, Mentor, powerpcb, etc.
Design rules for schematic diagrams: 1. The direction of the signal processing flow of the schematic diagram; 2. Connecting wires; 3. The methods and steps for identifying power cord and ground wire schematic diagrams.
