K4D551638F-TC Datasheet, PDF (14/16 Pages) Samsung semiconductor – 256Mbit GDDR SDRAM

K4D551638F-TC
Target Spec
256M GDDR SDRAM
AC CHARACTERISTICS (I)
Parameter
Symbol
Row cycle time
tRC
Refresh row cycle time
tRFC
Row active time
tRAS
RAS to CAS delay for Read
tRCDRD
RAS to CAS delay for Write
tRCDWR
Row precharge time
tRP
Row active to Row active
tRRD
Last data in to Row precharge @Nor-
mal Precharge
tWR
Last data in to Row precharge @Auto
Precharge
tWR_A
Last data in to Read command
tCDLR
Col. address to Col. address
tCCD
Mode register set cycle time
tMRD
Auto precharge write recovery + Pre-
charge
tDAL
Exit self refresh to read command tXSR
Power down exit time
tPDEX
Refresh interval time
tREF
-33
Min Max
15
-
17
-
10 100K
5
-
3
-
5
-
3
-
3
-
3
-
3
-
1
-
2
-
8
-
200
-
3tCK
+tIS
-
7.8
-
-36
Min Max
15
-
17
-
10 100K
5
-
3
-
5
-
3
-
3
-
3
-
2
-
1
-
2
-
8
-
200
-
3tCK
+tIS
-
7.8
-
-40
Min Max
13
-
15
-
9 100K
4
-
2
-
4
-
3
-
3
-
3
-
2
-
1
-
2
-
7
-
200
-
3tCK
+tIS
-
7.8
-
-50
Min Max
12
-
14
-
8 100K
4
-
2
-
4
-
2
-
3
-
3
-
2
-
1
-
2
-
7
-
200
-
1tCK
+tIS
-
7.8
-
Note : 1. For normal write operation, even numbers of Din are to be written inside DRAM
-60
Min Max
10
-
12
-
7 100K
3
-
2
-
3
-
2
-
3
-
3
-
1
-
1
-
2
-
6
-
200
-
1tCK
+tIS
-
7.8
-
Unit Note
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK 1
tCK 1
tCK 1
tCK
tCK
tCK
tCK
ns
us
AC CHARACTERISTICS (II)
K4D551638D-TC33
Frequency
Cas Latency tRC
300MHz ( 3.3ns )
3
15
tRFC
17
tRAS tRCDRD tRCDWR tRP
10
5
3
5
(Unit : Number of Clock)
tRRD
3
tDAL Unit
8
tCK
K4D551638D-TC36
Frequency
Cas Latency tRC
275MHz ( 3.6ns )
3
15
tRFC
17
tRAS tRCDRD tRCDWR tRP
10
5
3
5
tRRD
3
tDAL Unit
8
tCK
K4D551638D-TC40
Frequency
Cas Latency tRC
250MHz ( 4.0ns )
3
13
200MHz ( 5.0ns )
3
12
tRFC
15
14
tRAS tRCDRD tRCDWR tRP
9
4
2
4
8
4
2
4
tRRD
3
3
tDAL Unit
7
tCK
7
tCK
K4D551638D-TC50
Frequency
Cas Latency tRC
200MHz ( 5.0ns )
3
12
tRFC
14
tRAS tRCDRD tRCDWR tRP
8
4
2
4
tRRD
3
tDAL Unit
7
tCK
K4D551638D-TC60
Frequency
Cas Latency tRC
166MHz ( 6.0ns )
3
10
tRFC
12
tRAS tRCDRD tRCDWR tRP
7
3
2
3
tRRD
2
tDAL Unit
6
tCK
- 14 -
Rev 1.7 (June 2004)