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以后上传图片。具体的说法如下:If crossing a plane split is completely unavoidable, proper placement of stitching caps# X3 [3 q6 |5 N! j. x/ k$ U
can minimize the adverse effects of EMI and signal quality performance caused by4 r$ I% z/ S8 A# g& q4 v* W$ u
crossing the split. Stitching capacitors are small-valued capacitors (1 μF or lower in
7 F6 D1 v* A; @value) that bridge voltage plane splits close to where high-speed signals or clocks cross5 w5 D/ _ K6 Y: L# D
the plane split. The capacitor ends should tie to each plane separated by the split. They+ O- R8 R" ~ g" Y/ T
are also used to bridge (or bypass) power and ground planes close to where a highspeed
% Y) m3 t$ {- Zsignal changes layers. As an example of bridging plane splits, a plane split that
) T2 x$ U D- g* K/ W/ D7 Cseparates V5REF and Vcc3.3 planes should have a stitching cap placed near any highspeed
2 x0 ]* l+ |3 u8 csignal crossing. One side of the cap should tie to V5REF and the other side
/ w- \" q. d2 C& ]1 W% Dshould tie to Vcc3.3. Stitching caps provide a high frequency current return path across6 ~# _! B2 D+ S; Q6 T% M5 f
plane splits. They minimize the impedance discontinuity and current loop area that
% K0 _, P5 {! D: r$ I( ~# ]crossing a plane split creates.3 `) s+ d, ]: A' j% V/ E; [
以上是对USB3.0跨moat 的处理, 希望帮到大家 |
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