作者: chq_yanxue 时间: 2014-3-5 23:51
直接点击“Apply Value”作者: TanAiHeong 时间: 2014-4-10 19:16
Hi, this mean the output impedance of your driver(may get from the IBIS model) is large and your series terminator may not be effective. However, this is depend on the Zo of your topology. Based on the figure, it shows your Zo is controlled at 76Ohm(which is quite high for single ended signaling, std is 50Ohm +/- 10% and 60Ohm is acceptable) and the suggested value is ~20Ohm to match with your effective Zo. So, your whole channel will be simulated at ~60Ohm. If the driver impedance is too quite and significantly out of the Z0 range, it may cause multiple voltage reflection which lead to an underdamped/undamped issues作者: 格林杨 时间: 2014-4-17 17:10
Driver impedance 过大难道不是会失配引起反射吗
