Semiconductor Group
6-85
1999-04-01
On-Chip Peripheral Components
C541U
Figure 6-36
Full Speed USB Driver Signal Waveforms
For a low speed USB connection the rise and fall time of the signals are greater than 75 ns to keep
RFI emissions under FCC class B limits, and less than 300 ns to limit timing delays and signaling
skews and distortions. The driver reaches the specified static signal levels with smooth rise and fall
times, and minimal reflections and ringing when driving the USB cable (see figure 6-37). This cable
and driver are used only on network segments between low speed devices and the ports to which
they are connected.
Figure 6-37
Low Speed USB Driver Signal Waveforms
One Bit Time
(12 MB/s)
One-Way Trip Cable Delay
V
SS
Receiver
Signal Pins
Signal Pins
Driver
Signal Pins Pass
Input Spec Levels
after one Cable
Delay
SS
V
SE
V
max
SE
V
min
MCT03414
One Bit Time
(1.5 MB/s)
V
SS
Driver
Signal Pins
Signal Pins Pass
Output Spec Levels
with minimal Reflections
and ringing
SE
V
max
SE
V
min
MCT03415
Summary of Contents for C541U
Page 1: ... 8 LW 026 0LFURFRQWUROOHU 8VHU V 0DQXDO http www siem ens d Sem iconductor ...
Page 7: ......
Page 21: ...Semiconductor Group 2 6 1997 10 01 Fundamental Structure C541U ...
Page 37: ...Semiconductor Group 4 6 1997 10 01 External Bus Interface C541U ...
Page 133: ...Semiconductor Group 6 88 1999 04 01 On Chip Peripheral Components C541U ...
Page 163: ...Semiconductor Group 8 8 1997 10 01 Fail Safe Mechanisms C541U ...
Page 185: ...Semiconductor Group 10 14 1997 10 01 OTP Memory Operation C541U ...
