USB2244 Standard Microsystems Corp., USB2244 Datasheet - Page 20

• Manufacturer Part Number: USB2244
• Description: Usb2244/usb2244i Ultra Fast Usb 2.0 Sd/mmc Flash Media Controller
• Manufacturer: Standard Microsystems Corp.

Chapter 8 AC Specifications
Revision 1.0 (05-27-08)
8.1
C
C
1
2
Crystal: Parallel Resonant, Fundamental Mode, 24 MHz ± 100ppm.
External Clock: 50% Duty cycle ± 10%, 24 MHz ± 100ppm, Jitter < 100ps rms.
Note: C
Oscillator/Clock
B
equals total board/trace capacitance.
Figure 8.2 Formula to Find Value of C
Crystal
(C
(C
Figure 8.1 Typical Crystal Circuit
1
1
+ C
+ C
S1
C
S1
DATASHEET
) x (C
L
+ C
20
2
2
+ C
+ C
S2
S2
Ultra Fast USB 2.0 SD/MMC Flash Media Controller
)
)
1Meg
1
and C
=
2
C
L
SMSC USB2244/USB2244i
C
C
B
B
XTAL2
XTAL1
(C
+ C
(C
+ C
S2 =
S1 =
XTAL
XTAL
Datasheet
)
)