Marvel Group 88F6281 Sdram DDR2 Interface AC Timing Table, MHz @ Description Symbol Min Max

88F6281

Hardware Specifications

8.6.2SDRAM DDR2 Interface AC Timing

8.6.2.1SDRAM DDR2 Interface AC Timing Table

Table 46: SDRAM DDR2 Interface AC Timing Table

		400 MHz @ 1.8V
Description	Symbol	Min		Max	Units	Notes
Clock frequency	fCK		400.0		MHz	-
DQ and DM valid output time before DQS transition	tDOVB	0.40		-	ns	-
DQ and DM valid output time after DQS transition	tDOVA	0.40		-	ns	-
DQ and DM output pulse w idth	tDIPW	0.35		-	tCK(avg)	-
DQS output high pulse w idth	tDQSH	0.35		-	tCK(avg)	-
DQS output low pulse w idth	tDQSL	0.35		-	tCK(avg)	-
DQS falling edge to CLK-CLKn rising edge	tDSS	0.34		-	tCK(avg)	1
DQS falling edge from CLK-CLKn rising edge	tDSH	0.34		-	tCK(avg)	1
DQS latching rising transitions to associated clock edges	tDQSS	-0.11		0.11	tCK(avg)	-
DQS w rite preamble	tWPRE	0.35		-	tCK(avg)	-
DQS w rite postamble	tWPST	0.40		-	tCK(avg)	-
Average CLK-CLKn high-level w idth	tCH(avg)	0.48		0.52	tCK(avg)	1, 2, 3
Average CLK-CLKn low -level w idth	tCL(avg)	0.48		0.52	tCK(avg)	1, 2, 4
DQ input setup time relative to DQS in transition	tDSI	-0.42		-	ns	-
DQ input hold time relative to DQS in transition	tDHI	0.70		-	ns	-
Address and control output pulse w idth	tIPW	0.60		-	tCK(avg)	-

Notes:

General comment: All timing values are defined from Vref to Vref, unless otherw ise specified.

General comment: All input timing values assume minimum slew rate of 1 V/ns (slew rate defined from Vref +/-125 mV).

General comment: tCK(avg) is calculated as the average clock period across any consecutive 200 cycle w indow .

General comment: All timing parameters w ith DQS signal are defined on DQS-DQSn crossing point.

General comment: For Address and Control output timing parameters, refer to the Address Timing table.

General comment: For all signals, the load is CL = 14 pF.

1.This timing value is defined on CLK / CLKn crossing point.

2.Refer to SDRAM DDR2 clock specifications table for more information.

3.tCH(avg) is defined as the average HIGH pulse w idth, as calculated across any consecutive 200 HIGH pulses.

4.tCL(avg) is defined as the average LOW pulse w idth, as calculated across any consecutive 200 LOW pulses.

Doc. No. MV-S104859-U0 Rev. E		Copyright © 2008 Marvell
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