做真实的自己！
分类： 信息化
2015-03-02 14:11:23
If the transmission line is longer than wavelength/10, then termination is required.
RATIONALE
Use below equation to determine wavelength,
wavelength = speed / frequency
frequency = 0.35 / Tr ; Tr is the rise time from 10%~90%
speed = 1/( 85 x sqr(?r)) for stripline, and
speed = 1/( 85 x sqr(0.475*?r+0.67)) for microstrip, ?r is the material dielectric constant.
