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CHAPTER 4 BUS INTERFACE
4.17.15 Single DRAM Interface: Write
This section provides a single DRAM interface write timing chart.
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Single DRAM Interface: Write Timing Chart
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Bus width: 16 bits, access: words
Figure 4.17-30 Example of Single DRAM Interface Write Timing Chart
[Explanation of operation]
• Column addresses and write data are output in Q4SW cycles.
• CAS is asserted at the falling edge of Q4SW and negated at the rising edge or end of the
Q4SW cycle.
•WE
(including WEL and WEH) is asserted at the rising edge of the Q4SW cycle and negated
when Q4SW ends.
Q1 Q2 Q3 Q4SW Q4SW Q4SW Q4SW Q1 Q2 Q3 Q4SW
CLK
2)2CAS/1WE
A24-00
X row.adr. col. col. col. col. X row.adr. col.
D31-24 W W W W W
D23-16 W W W W W
RAS
CASL
CASH
WE
RDX
(DACK0)
(EOP0)
High speed
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High speed
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High speed
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