1、名词解释

• ERC：Electrical Rule Check
• BT-Epoxy：环氧树脂,PCB材料

2、局限性

• Vias cannot simulate characteristic impedance
• series resistance andAC CouplingCapacitors cannot simulate characteristic impedance

3、仿真过程

3.1、Load the board（.brd或.spd）

3.2、Check Stack-up（至关重要）

根据 Set up your own board stackPowerSI的stack up（The following stackup parameters are inaccurate）

设置过孔参数：

3.3、Prepare Net

备注：电源的Pairing P/G NetBe sure to choose the appropriate oneGround,这里上GND;Personally understand that the voltage value here should not be very important.

3.4、Enable Trace Check Mode

3.4.1、Optional：Setup Net Groups

前提：The differential pair has been set up in advance,⊕The positive pole representing the differential pair also needs to be set.

TX：

 RX：

 P/G Nets：

 Passive Components（个人理解：Value并不重要,The result will not be reflected anywaypassive Component上）：

 Net Group Pre-View：

On the basis of the above, add what needs to be simulatedNet Group,再次点击“Optional：Setup Net Groups”

 TX：

RX：

 P/G Net：

Passive Components（个人理解：Value并不重要,The result will not be reflected anywaypassive Component上）：

3.4.2、Optional：Show Net Groups

3.5、Setup Trace Check Parameter

这里一定要选择“Check by NetGroup”：

 3.6、Save File without Error Check

注意Output窗口,一定不能有Error

3.7、Start Simlution

3.8、查看结果

3.8.1、Impedance Summary Table（Only single ended,Differential is also presented in single-ended form）

 3.8.2、Impedance Detail Table

Each segment of the trace is presented individually,并且会有RLCparameters and transmission delays.

3.8.3、Impedance Plot（collapsed）

Net group1 单端：

 Net group1 差分：

Net group2 单端：

4、反思

From the simulation results above,Obviously expected100Ohmic impedance only89欧姆,这就是仿真的时候Stack-upThe correct result is not set.

 重新设置Stack up：

 重新仿真,得到如下结果,close to the expected value,But there are still some gaps,There must be a difference in the parameter settings,But the exact reason is unknown.