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1. ' ............................. 3

1.1 ' ......................................................................... 3

1.2 ϳ-....................................................................... 6

1.3 ........................................................... 7

1.4 .................................................. 7

1.5 ............................................................................. 8

2. ' 䳿..11

2.1 FPM............................................................................................. ...11

2.2 EDORAM....................................................................... ...12

2.3 BEDORAM.................................................................... ...13

2.4 MDRAM......................................................................... ...13

2.5 SDRAM.......................................................................... ...14

2.6 RDRAM......................................................................... ...17

2.7 DRDRAM............................................................................... ...17

2.8 CDRAM......................................................................... ...18

3. ' .18
4. ......................................................................... ...21

5. ˳...................................................................................................... ...23

' -

(DRAM) - () . , 6 , ( 45 ) . , ( ).

'

³ . - , , α-,      ().

. 1. .

. 1. - . . . ̳ - Si02.

. , . ' - - -. - , .

' . (. 2) , () 1 0 . - () , . , .


. 2. .

. .

. , U/2. , , .

, .


, . ΔU, , . , , U . ' ΔU. . 3.

. 3. .

ΔU . .

Q = UCC/2.

ϳ + :

Q = (+ )(UCC/2  ΔU).

Q,

UCC/2 = (+ )(UCC/2  ΔU),

ΔU = UCC/[2(+)] ≈ UCC/[2 ].

<< ΔU . , - ' .

̳ ( ), - .

( ҳ2), 20 , Si2. 20 . , .

"" (. 4, ). , , ' , ΔU.

. 4. - - () - ().

ϳ-

ϳ- . (. 4, ) "ϳ" 1 2. "ϳ" . - . , , U/2, , , ΔU , . T1 2. "ϳ" . T1 2 , , , . , . . -, . . , .

. , , . . RAS (Row Address Strobe), - CAS (Column Address Strobe). , , RAS CAS - (, ). , , , . , 161 24- , 12.

. 5 . . .

. 5. .

(. 6) , . , . - .

( ) , , 1 U/2 - . ( ). 1 - U/2, 1 1 2. 1 , , .

. 6. .

-, , , .

2 "ϳ" -, , - , .

R/W, ( 4 R/W = 1), ( 3 R/W = 0).

, , ' , ( , ) 1 2.

, , , "--". , (). , , . , . "--" , , .

' 䳿

䳺. , . , ' '.

䳿. , , . , , .

FPM

FPM (Fast Page Mode, ) , . .

, . , , .

(), , ( RAS), . , CAS. 3 4 (. . 6). , , .

FPM . 7. , RA ( ). : 5-3-3-... .

. 7. FPM .

FPM 䳿 . 䳿 , FPM , .

FPM : (), . () . FPM 30-40 , 33 .

EDORAM

EDORAM (Extended Data Out RAM, ) FPM . EDORAM -

EDORAM 50 . , FPM, EDORAM .

BEDORAM

BEDORAM (Burst EDORAM, ) . () . . 5-1-1-1 ( , 4). ' BEDORAM - DRAM (SDRAM), 5-1-1-1, .

MDRAM

MDRAM (Multibank DRAM, ) ' (). , . , , ' . '. , .

, ' , , - . MDRAM DRAM - .

SDRAM

DRAM FPM EDORAM ', ' . ' SDRAM (Synchronous DRAM) ' .

SDRAM ' ' , , ' .

DRAM 1994 . , 250 /. ֳ 125  U = 3,3  0,5 . (113,7 2) DRAM 򳺿 .

' SDRAM . . . 8 , . , :

Tmin = tpr + t + tSU ,

tpr - "-"; t - ( ); tSU - .

Tmin, , t , (. 8, ). , , , . 8, , .

. 8. () () .

, , , , .

SDRAM , . ACT (Active) ' . RED (Read) . PRE (Precharge) ' .

' (Access Latency). "", , . , ' (. 9, ). , (. 9, 6). . ³ (. 9, ).

SDRAM ' , .

. 9. (), () () .

SDRAM , . , () , . SDRAM ' .

RDRAM

̳ - Rambus (RDRAM Rambus DRAM). - ' . Rambus Channel. SDRAM.

250 500 (2 /). 1,5...3 .

Rambus Channel 13 , , '. . , . , ' , . . 128 . RDRAM . . 256 400 ( 2 0,5 ), 64 - 250 ..

RDRAM - .

DRDRAM

RDRAM, Direct RDRAM (DRDRAM). RDRAM , . , DRDRAM.

DRAM (SDRAM). ' , ', . ' DRDRAM . , SDRAM, DRDRAM , DRAM. . DRDRAM 16- ( RDRAM 8-). 400 DDR (Double Data Rate), , DRDRAM (Bandwidth) 1,6 /.

, , , 1,6 / .

CDRAM

CDRAM (Cached DRAM, DRAM) DRAM -' ( ). , , . ' , DRAM ' ( ), . , CDRAM Ramtron 2048- .

CDRAM EDRAM (Enhanced DRAM). , , , .

'

. ( 1 15 ).

. , . , .

tCY, N, t = tCYN. ³

τ = (t/ )

- .

, 1 1Mx1, 100 , 5 ,

τ = (100∙10-9∙210/5∙10-3) ∙100% = 2%

(210 = 1024 , 1 ' ).

, , . 10. ' , . . , - . 1 2 . 2 CTR, - RASp MUX2 MUX1.

. 10. .

'

G , . ij , ( ). , , ' , 1 . HOLD ' . . , . , HLDA, . HLDA 2, ', per, MUX2 CTR . 2 , ( 64). 1, HOLD. HLDA, 2, .

-' . ', . .

" " . 11, , . . 11, , . 11, , ' 䳿 . , . .

. 11. 䳿 () () ' .

˳

1.     .. .: ., 1987. 424 .

2.     . . C-, 2004. 528 .

3.     . . . .: , 1993. 63 .: .

4.     Internet: [ ] .: [200-?]. : http://www.whatis.ru/hard/mem.shtml . .

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