Datasheet

PIC18F2455/2550/4455/4550
DS39632E-page 402 © 2009 Microchip Technology Inc.
FIGURE 28-21: USB SIGNAL TIMING
TABLE 28-25: USB LOW-SPEED TIMING REQUIREMENTS
TABLE 28-26: USB FULL-SPEED REQUIREMENTS
VCRS
USB Data Differential Lines
90%
10%
TLR, TFR
TLF, TFF
Param
No.
Symbol Characteristic Min Typ Max Units Conditions
T01
T
LR Transition Rise Time 75 — 300 ns CL = 200 to 600 pF
T02 TLF Transition Fall Time 75 — 300 ns CL = 200 to 600 pF
T03 T
LRFM Rise/Fall Time Matching 80 — 125 %
Param
No.
Symbol Characteristic Min Typ Max Units Conditions
T04
T
FR Transition Rise Time 4 — 20 ns CL = 50 pF
T05 TFF Transition Fall Time 4 — 20 ns CL = 50 pF
T06 TFRFM Rise/Fall Time Matching 90 — 111.1 %