APPENDIX A <REFERENCE> EXTERNAL DEVICE INTERFACE TIMINGS
S1C33L03 PRODUCT PART EPSON A-117
A-1
A-ap
A.2 DRAM (60ns)
DRAM interface setup examples – 60ns
Operating
frequency
RAS precharge
cycle
RAS cycle CAS cycle
Refresh RAS pulse
width
Refresh RPC delay
20MHz 1 1 221
25MHz 2 1 221
33MHz 2 2 231
DRAM interface timing – 60ns
DRAM interface Unit: ns 33MHz 25MHz 20MHz
Parameter Symbol Min. Max. Cycle Time Cycle Time Cycle Time
<Common parameters>
Random read/random write cycle time tRC 110 – 6 18052004200
#RAS precharge time tRP 40 – 2 60 2 80 1 50
#RAS pulse width tRAS 60 10000 4 12031203150
#CAS pulse width tCAS 15 10000 1.5 45 1.5 60 1.5 75
Row address setup time tASR 0–0.5150.520 0.5 25
Row address hold time tRAH 10 – 1.5 45 0.5 20 0.5 25
Column address setup time tASC 0–0.5150.520 0.5 25
#RAS→#CAS delay time tRCD 20 – 2.0 60 1.0 40 1.0 50
#RAS→column address delay time tRAD 15 – 1.5 45 0.5 20 0.5 25
<Read-cycle parameters>
#RAS access time tRAC –603.51052.51002.5125
#CAS access time tCAC –151.545 1.5 60 1.5 75
Address access time tAA –302.0602.0 80 2.0 100
#OE access time tOAC –153.51052.51002.5125
Output buffer turn-off time tOFF 015260280150
<Write-cycle parameters>
Data input hold time tDH 10 – 1.5 45 1.5 60 1.5 75
<Fast-page mode>
Fast-page mode cycle time tPC 40 – 2.0 60 2.0 80 2.0 100
Fast-page mode #CAS precharge time tCP 10 – 0.5 15 0.5 20 0.5 25
Access time after #CAS precharge tACP –352.0602.0 80 2.0 100
<Refresh cycle>
#CAS setup time tCSR 10 – 1.0 30 1.0 40 1.0 50
#CAS hold time tCHR 10 – 2.5 75 1.5 60 1.5 75
#RAS precharge→#CAS hold time tPPC 10 – 1.0 30 1.0 40 1.0 50
#RAS pulse width (only in refresh cycle) tRAS 60 10000 3.0 90 2.0 80 2.0 100