Critical Signal in Electronic PC Board Cloning are playing important roles in the whole process of Printed Circuit Board EMC documents Reverse Engineering,
1. CS signal (sampling signal): pulled out from sampling resistors R25 and R26. Note that the ground wire of the IC is based on the sampling resistor, and the positive and negative differential traces of the sampling resistor pull down the IC CS pin and IC’s GND pin.
2. The drive signal pulls down the IC drive pin from the drive circuit, and be careful not to interfere with the CS pin; as shown in the figure, the three wires are routed side by side, and the ground wire is routed between the drive and the CS wire to play a certain shielding effect;
3. It is best to shield the IC with one layer of ground for the double-sided board. The grounded network must be drawn from the IC GND. The non-critical signal GND can be directly punched. The critical signal ground needs to be grounded at a single point and directly connected to the IC;
4. FB feedback network signal pay attention to check the wiring and connect to IC at a single point;
5. RCD absorption network should not be placed in the main circuit;
6. The rectifier and filter ground of VCC needs to be connected to the main power ground, and the secondary filter can be connected to the IC ground;
7. The Y capacitor wiring is connected separately, and it should not be confused with the main power to avoid interference.
Above Critical Signal in Electronic PC Board Cloning must be paid attention in order to ensure the preciseness of circuit board schematic diagram recovery;