Epson Research and Development

Page 53

Vancouver Design Center

7.3.4 EDO-DRAM CAS Before RAS Refresh Timing

t1

 

Memory

 

Clock

 

t2

t3

RAS#

 

CAS#

 

t4

t5

t6

 

Figure 7-10: EDO-DRAM CAS Before RAS Refresh Timing

Table 7-10: EDO-DRAM CAS Before RAS Refresh Timing

Symbol

Parameter

Min

Typ

Max

Units

 

 

 

 

 

 

t1

Memory clock period

25

 

 

ns

 

 

 

 

 

 

t2

RAS# to CAS# precharge time (REG[22h] bits [3:2] = 00)

1.45 t1

 

 

ns

 

 

 

 

 

RAS# to CAS# precharge time (REG[22h] bits [3:2] = 01 or 10)

0.45 t1

 

 

ns

 

 

 

 

 

 

 

 

 

 

Random read or write cycle time (REG[22h] bits [6:5] = 00)

5 t1

 

 

ns

 

 

 

 

 

 

t3

Random read or write cycle time (REG[22h] bits [6:5] = 01)

4 t1

 

 

ns

 

 

 

 

 

 

 

Random read or write cycle time (REG[22h] bits [6:5] = 10)

3 t1

 

 

ns

 

 

 

 

 

 

t4

CAS# precharge time (REG[22h] bits [3:2] = 00)

2 t1

 

 

ns

 

 

 

 

 

CAS# precharge time (REG[22h] bits [3:2] = 01 or 10)

1 t1

 

 

ns

 

 

 

 

 

 

 

 

 

t5

CAS# setup time (REG[22h] bits [3:2] = 00 or 10)

0.45 t1 - 2

 

 

ns

 

 

 

 

 

CAS# setup time (REG[22h] bits [3:2] = 01)

1 t1 - 2

 

 

ns

 

 

 

 

 

 

 

 

 

 

RAS# precharge time (REG[22h] bits [3:2] = 00)

2 t1 - 1

 

 

ns

 

 

 

 

 

 

t6

RAS# precharge time (REG[22h] bits [3:2] = 01)

1.45 t1 - 1

 

 

ns

 

 

 

 

 

 

 

RAS# precharge time (REG[22h] bits [3:2] = 10)

1 t1 - 1

 

 

ns

 

 

 

 

 

 

Hardware Functional Specification

S1D13504

Issue Date: 01/01/30

X19A-A-002-18

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Image 59
Epson S1D13504 manual EDO-DRAM CAS Before RAS Refresh Timing