Electrical Specifications

32579B

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Rise Time

Fall Time

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CL

 

 

90%

90%

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Differential

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Data Lines

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10%

 

 

 

 

 

 

 

 

10%

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CL

tUSB_R1,2tUSB_F1,2

Full Speed: 4 to 20 ns at CL = 50 pF

Low Speed: 75 ns at CL = 50 pF, 300 ns at CL = 350 pF

Figure 9-38. USB Data Signal Rise and Fall Timing Diagram

tUSB_DJ11 tUSB_DJD21 tUSB_DJU21

tperiod_F tperiod_L

Differential Data Lines

Crossover Points

(1.3-2.0) V

Consecutive Transitions

N*tperiod_F + tUSB_DJ11

N*tperiod_L + tUSB_DJD21

N*tperiod_L + tUSB_DJU21

Paired Transitions

N*tperiod_F + tUSB_DJ12

N*tperiod_L + tUSB_DJD22

N*tperiod_L + tUSB_DJU22

tUSB_DJ12 tUSB_DJD22 tUSB_DJU22

Figure 9-39. USB Source Differential Data Jitter Timing Diagram

AMD Geode™ SC1200/SC1201 Processor Data Book

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AMD SC1201, SC1200 manual Rise Time Fall Time, Differential Data Lines Crossover Points 2.0, Consecutive Transitions