USB2640I Standard Microsystems Corp., USB2640I Datasheet - Page 58

• Manufacturer Part Number: USB2640I
• Description: Industrial Temperature Usb 2.0 Flash Media Controller And Usb Hub Combo
• Manufacturer: Standard Microsystems Corp.

Chapter 10 AC Specifications
Revision 2.0 (10-03-08)
10.1
Crystal: Parallel Resonant, Fundamental Mode, 24 MHz ± 100 ppm.
External Clock: 50% Duty cycle ± 10%, 24 MHz ± 100 ppm, Jitter < 100 ps rms.
Note: C
Oscillator/Clock
C
C
B
1
2
equals total board/trace capacitance.
Figure 10.2 Formula to find value of C
Figure 10.1 Typical Crystal Circuit
Crystal
C
L
=
Industrial Temperature USB 2.0 Flash Media Controller and USB Hub Combo
DATASHEET
C
(C
L
(C
1
1
+ C
+ C
58
S1
S1
) x (C
+ C
1Meg
2
2
+ C
+ C
S2
S2
)
)
1
and C
C
C
B
B
XTAL2
XTAL1
(C
+ C
(C
+ C
21
S2 =
S1 =
XTAL
XTAL
)
)
SMSC USB2640i/USB2641i