Separate the low level analog circuit from the digital circuit to avoid the common impedance coupling between the analog circuit, the digital circuit and the common circuit of the power supply.
PCBS with multiple layers are often used in high-speed, high-performance systems, where the multiple layers are used for direct current (DC) power supplies or ground reference planes.
With both analog and digital functions of the circuit board, analog and digital are usually separated, only connected at the power source.
Although the decoupling capacitor can be placed near the through-hole, it is rendered useless at high frequencies due to the lead and through-hole inductance. Such routing will increase the area of signal ring and reduce the current radiation unfavorably.
When selecting the driver chip, in addition to ensuring that it basically matches the load and that the signal edge meets the requirements (generally, the clock is an effective signal along the clock), the time delay of the clock in the driver chip should
That is to say, the digital-to-analog undivided way can only be used when the analog circuit area is far away from the digital circuit area that generates large noise.
What problems should we pay attention to in PCB laminated design? Let a professional engineer tell you. Two rules must be followed in the design of lamination
Factors related to EMC issues in PCB design: 1. System design: 2. Structural impact: 3. Cable influence: 4. Component selection: 5. Related to SI/PI simulation: 6. Grounding, 7.PCB design relationship, 8. Software anti-jamming technology: 9. Shielding: 10
Solutions to impedance discontinuity problems in PCB design: 1. Gradient line, 2. Corner, 3. Large pad, 4. Through hole, 5. Through hole coaxial connector
The other is ground (or low potential) noise, that is, ground noise caused by the potential difference between ground wires in various parts of the system or by the presence of ground impedance.
In practical EMI shielding, the electromagnetic shielding efficiency depends largely on the physical structure of the chassis, namely, the continuity of conduction. The seams and openings in the chassis are leakage sources of electromagnetic waves.
The generation of grooving can be summarized into the following two cases :1. Grooving caused by power/ground plane segmentation; 2.the through hole is too dense to form grooves.