SMSC USB4640i ユーザーズマニュアル
High Speed Inter-Chip USB 2.0 Hub and Flash Media Controller
Datasheet
SMSC USB4640/USB4640i
55
Revision 1.0 (06-01-09)
DATASHEET
9.2
Ceramic Resonator
24 MHz
± 350 ppm
Figure 9.3 Ceramic Resonator Usage with SMSC IC
9.3
External Clock
50% Duty cycle
± 10%, 24 MHz ± 350 ppm, Jitter < 100 ps rms.
The external clock is recommended to conform to the signaling level designated in the JESD76-2
specification on 1.8 V CMOS Logic. XTAL2 should be treated as a no connect.
specification on 1.8 V CMOS Logic. XTAL2 should be treated as a no connect.
9.3.1
I
2
C EEPROM
Frequency is fixed at 58.6 kHz
± 20%
9.3.2
USB 2.0
The SMSC device conforms to all voltage, power, and timing characteristics and specifications as set
forth in the USB 2.0 Specification. Please refer to the USB 2.0 Specification for more information.
forth in the USB 2.0 Specification. Please refer to the USB 2.0 Specification for more information.