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PIC18F2455_07 Datasheet, PDF (397/430 Pages) Microchip Technology – 28/40/44-Pin, High Performance, Enhanced Flash, USB Microcontrollers with nanoWatt Technology
PIC18F2455/2550/4455/4550
FIGURE 28-21:
USB SIGNAL TIMING
USB Data Differential Lines
90%
VCRS
10%
TLR, TFR
TLF, TFF
TABLE 28-25: USB LOW-SPEED TIMING REQUIREMENTS
Param
No.
Symbol
Characteristic
Min Typ
TLR
TLF
TLRFM
Transition Rise Time
Transition Fall Time
Rise/Fall Time Matching
75
—
75
—
80
—
Max Units
Conditions
300
ns CL = 200 to 600 pF
300
ns CL = 200 to 600 pF
125
%
TABLE 28-26: USB FULL-SPEED REQUIREMENTS
Param
No.
Symbol
Characteristic
Min
TFR
Transition Rise Time
4
TFF
Transition Fall Time
4
TFRFM Rise/Fall Time Matching
90
Typ Max Units
Conditions
—
20
ns CL = 50 pF
—
20
ns CL = 50 pF
— 111.1 %
© 2007 Microchip Technology Inc.
Preliminary
DS39632D-page 395