Marvel Group 88F6281 Table 45: Reference Clock AC Timing Specifications (Continued)

Electrical Specifications
AC Electrical Specifications
Copyright © 2008 Marvell Doc. No. MV-S104859-U0 Rev. E
December 2, 2008, Preliminary Document Classification: Proprietary Information Page 87
Notes:
1. Slew rate is defined from 20% to 80% of the reference clock signal.
2. For additional information regarding configuring this clock, see the Serial Memory Interface
Control Register in the 88F6180, 88F6190, 88F6192, and 88F6281 Functional Specifications.
3. Fs is the audio sample rate, which can be configured to 44.1 kHz, 48 kHz, or 96 kHz (see the
Audio (I2S / S/PDIF) Interface section in the 88F6180, 88F6190, 88F6192, and 88F6281
Functional Specifications).
4. The RTC design was optimized for a standard CL = 12.5 pF crystal. No passive components
are provided internally. Connect the crystal and the passive network as recommended by the
crystal manufacturer.
5. The frequency can be set using the TS Interface Configuration register (see the 88F6180,
88F6190, 88F6192, and 88F6281 Functional Specifications).
6. For the minimum value refer to the Baud Rate Register section of the 88F6180, 88F6190,
88F6192, and 88F6281 Functional Specifications.
7. The Ethernet Reference Clock parameters refer both to the reference clock for an Ethernet port
configured using the dedicated port pins and for an Ethernet port configured using the
multiplexed port pins.
TDM_SPI Output Clock
TDM_SPI output clock FTDM_SPI_SCK 8.192 MHz
SMI Master Mode Reference Clock
SMI output MDC clock FGE_MDC TCLK/128 MHz
TWSI Master Mode Reference Clock
SCK output clock FTW_SCK TCLK/
1600 kHz 6
PTP Reference Clock
Frequency FPTP_CLK 125 -
100ppm 125 + 100ppm MHz
Clock duty cycle DCPTP_CLK 40 60 %
Slew rate SRPTP_CLK 0.7 V/ns 1
Pk-Pk jitter JRPTP_CLK 100 ps
Table 45: Reference Clock AC Timing Specifications (Continued)
Description Symbol Min Max Units Notes