8Mb: 512K x 16 Async/Page/Burst CellularRAM 1.0 Memory
Features
Async/Page/Burst
CellularRAM
®
1.0 Memory
MT45W512KW16BEGB
Features
• Single device supports asynchronous, page, and
burst operations
• Random access time: 70ns
• V
CC
, V
CC
Q voltages
–
1.7–1.95V V
CC
–
1.7–3.6V
1
V
CC
Q
• Page mode read access
–
16-word page size
–
Interpage read access: 70ns
–
Intrapage read access: 20ns
• Burst mode write access: continuous burst
• Burst mode read access
–
4, 8, or 16 words or continuous burst
–
MAX clock rate: 104 MHz (
t
CLK = 9.62ns)
–
Burst initial latency: 38.5ns (4 clocks) at 104 MHz
–
t
ACLK: 7ns at 104 MHz
• Low power consumption
–
Asynchronous read: <20mA
–
Intrapage read: <15mA
–
Intrapage read initial access, burst read:
(38.5ns [4 clocks] at 104 MHz) <35mA
–
Continuous burst read: <28mA
–
Standby: <65µA
–
Deep power-down (DPD): <10µA (TYP at 25°C)
• Low-power features
–
Partial-array refresh (PAR)
–
DPD mode
Figure 1:
54-Ball VFBGA Ball Assignment
1
A
B
C
D
E
F
G
H
J
LB#
2
OE#
3
A0
4
A1
5
A2
6
CRE
DQ8
UB#
A3
A4
CE#
DQ0
DQ9
DQ10
A5
A6
DQ1
DQ2
V
SS
Q
DQ11
A17
A7
DQ3
V
CC
V
CC
Q
DQ12
NC
A16
DQ4
V
SS
DQ14
DQ13
A14
A15
DQ5
DQ6
DQ15
NC
A12
A13
WE#
DQ7
A18
A8
A9
A10
A11
NC
WAIT
CLK
ADV#
NC
NC
NC
Top view
(Ball down)
Options
• Configuration
–
512K x 16
• Package
–
54-ball VFBGA (“green”)
• Access time
–
70ns
• Frequency
–
80 MHz
–
104 MHz
• Standby power
–
Standard
Designator
MT45W512KW16BE
GB
-70
8
1
None
Options (continued)
• Operating temperature range
–
Wireless (–30°C to +85°C)
1
–
Industrial (–40°C to +85°C)
2
Designator
WT
IT
Notes: 1. The 3.6V I/O and the –30°C wireless temper-
ature exceed the CellularRAM Workgroup 1.0
specification.
2. Contact factory for availability.
Part Number Example:
MT45W512KW16BEGB-701WT
1
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2007 Micron Technology, Inc. All rights reserved.
PDF: 09005aef82e41987 / Source: 09005aef82e419a5
8mb_4mb_burst_cr1_0_p22z__1.fm - Rev. C 4/ 08 EN
Products and specifications discussed herein are subject to change by Micron without notice.
8Mb: 512K x 16 Async/Page/Burst CellularRAM 1.0 Memory
Table of Contents
Table of Contents
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
List of Tables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Functional Block Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Ball Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Bus Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Part Numbering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Valid Part Number Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Device Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Power-Up Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Bus Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Asynchronous Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Page Mode READ Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Burst Mode Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Mixed-Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
WAIT Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
LB#/UB# Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Low-Power Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Standby Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Deep Power-Down Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Configuration Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Access Using CRE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Software Access to the Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Bus Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Burst Length (BCR[2:0]) Default = Continuous Burst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Burst Wrap (BCR[3]) Default = Burst No Wrap (Within Burst Length) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Output Impedance (BCR[5]) Default = Outputs Use Full-Drive Strength. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
WAIT Configuration (BCR[8]) Default = WAIT Transitions One Clock Before Data Valid/Invalid . . . . . . . . .26
WAIT Polarity (BCR[10]) Default = WAIT Active HIGH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Latency Counter (BCR[13:11]) Default = Three-Clock Latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Operating Mode (BCR[15]) Default = Asynchronous Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Refresh Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Partial-Array Refresh (RCR[2:0]) Default = Full Array Refresh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Deep Power-Down (RCR[4]) Default = DPD Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Page Mode Operation (RCR[7]) Default = Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Typical Standby Currents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Timing Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Timing Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Package Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
Revision History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
PDF: 09005aef82e41987 / Source: 09005aef82e419a5
4mb_burst_cr1_0_p22zTOC.fm - Rev. B 4/ 08 EN
2
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2007 Micron Technology, Inc. All rights reserved.
8Mb: 512K x 16 Async/Page/Burst CellularRAM 1.0 Memory
List of Figures
List of Figures
Figure 1:
Figure 2:
Figure 3:
Figure 4:
Figure 5:
Figure 6:
Figure 7:
Figure 8:
Figure 9:
Figure 10:
Figure 11:
Figure 12:
Figure 13:
Figure 14:
Figure 15:
Figure 16:
Figure 17:
Figure 18:
Figure 19:
Figure 20:
Figure 21:
Figure 22:
Figure 23:
Figure 24:
Figure 25:
Figure 26:
Figure 27:
Figure 28:
Figure 29:
Figure 30:
Figure 31:
Figure 32:
Figure 33:
Figure 34:
Figure 35:
Figure 36:
Figure 37:
Figure 38:
Figure 39:
Figure 40:
Figure 41:
Figure 42:
Figure 43:
Figure 44:
Figure 45:
Figure 46:
Figure 47:
Figure 48:
Figure 49:
54-Ball VFBGA Ball Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Functional Block Diagram (512K x 16) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Part Number Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Power-Up Initialization Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
READ Operation (ADV = LOW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
WRITE Operation (ADV = LOW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Page Mode READ Operation (ADV = LOW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Burst Mode READ (4-Word Burst) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Burst Mode WRITE (4-Word Burst) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Wired-OR WAIT Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Refresh Collision During READ Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Refresh Collision During WRITE Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Asynchronous Mode Configuration Register Write Followed by READ ARRAY Operation . . . . . . .18
Synchronous Mode Configuration Register WRITE Followed by READ ARRAY Operation . . . . . . .19
Asynchronous Mode Configuration Register READ Followed by READ ARRAY Operation . . . . . . .20
Synchronous Mode Configuration Register READ Followed by READ ARRAY Operation . . . . . . . .21
Load Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Read Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Bus Configuration Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
WAIT Configuration (BCR[8] = 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
WAIT Configuration (BCR[8] = 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
WAIT Configuration During Burst Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Latency Counter (Variable Latency, No Refresh Collision) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Refresh Configuration Register Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Typical Refresh Current vs. Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
AC Input/Output Reference Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Output Load Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Initialization Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Asynchronous READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Asynchronous READ Using ADV# . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Page Mode READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Single-Access Burst READ Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Four-Word Burst READ Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
READ Burst Suspend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Output Delay in Continuous Burst READ with BCR[8] = 0 for End-of-Row Condition . . . . . . . . . . .43
CE#-Controlled Asynchronous WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
LB#/UB#-Controlled Asynchronous WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
WE#-Controlled Asynchronous WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Asynchronous WRITE Using ADV# . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
Burst WRITE Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Output Delay in Continuous Burst Write with BCR[8] = 0 for End-of-Row Condition . . . . . . . . . . . .49
Burst WRITE Followed by Burst READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Asynchronous WRITE Followed by Burst READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Asynchronous WRITE Followed by Burst READ with ADV# LOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Burst READ Followed by Asynchronous WRITE (WE#-Controlled) . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
Burst READ Followed by Asynchronous WRITE Using ADV# . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Asynchronous WRITE Followed by Asynchronous READ – ADV# LOW . . . . . . . . . . . . . . . . . . . . . . . .55
Asynchronous WRITE Followed by Asynchronous READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
54-Ball VFBGA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
PDF: 09005aef82e41987 / Source: 09005aef82e419a5
4mb_burst_cr1_0_p22zLOF.fm - Rev. B 4/ 08 EN
3
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2007 Micron Technology, Inc. All rights reserved.
8Mb: 512K x 16 Async/Page/Burst CellularRAM 1.0 Memory
List of Tables
List of Tables
Table 1:
Table 2:
Table 3:
Table 4:
Table 5:
Table 6:
Table 7:
Table 8:
Table 9:
Table 10:
Table 11:
Table 12:
Table 13:
Table 14:
VFBGA Ball Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Bus Operations: Asynchronous Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Bus Operations: Burst Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Sequence and Burst Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Latency Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Electrical Characteristics and Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Deep Power-Down Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Asynchronous READ Cycle Timing Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Burst READ Cycle Timing Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Asynchronous WRITE Cycle Timing Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Burst WRITE Cycle Timing Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Initialization Timing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
PDF: 09005aef82e41987 / Source: 09005aef82e419a5
4mb_burst_cr1_0_p22zLOT.fm - Rev. B 4/ 08 EN
4
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2007 Micron Technology, Inc. All rights reserved.
8Mb: 512K x 16 Async/Page/Burst CellularRAM 1.0 Memory
General Description
General Description
Micron
®
CellularRAM
®
is a high-speed, CMOS PSRAM memory developed for low-
power, portable applications. The MT45W512KW16BEGB is an 8Mb DRAM core
device organized as 512K x 16 bits. This device includes an industry-standard burst
mode Flash interface that dramatically increases read/write bandwidth compared with
other low-power SRAM or pseudo-SRAM (PSRAM) offerings.
For seamless operation on a burst Flash bus, CellularRAM products incorporate a trans-
parent self refresh mechanism. The hidden refresh requires no additional support from
the system memory controller and has no significant impact on device read/write
performance.
Two user-accessible control registers define device operation. The bus configuration
register (BCR) defines how the CellularRAM device interacts with the system memory
bus and is nearly identical to its counterpart on burst mode Flash devices. The refresh
configuration register (RCR) is used to control how refresh is performed on the DRAM
array. These registers are automatically loaded with default settings during power-up
and can be updated anytime during normal operation.
Special attention has been focused on standby current consumption during self refresh.
This CellularRAM product includes two system-accessible mechanisms to minimize
standby current. Partial-array refresh (PAR) limits refresh to only that part of the DRAM
array that contains essential data. Deep power-down (DPD) halts the REFRESH opera-
tion altogether and is used when no vital information is stored in the device. These two
refresh mechanisms are accessed through the RCR.
Functional Block Diagrams
Figure 2:
Functional Block Diagram (512K x 16)
A[18:0]
Address decode
logic
512K x 16
DRAM
memory
array
Input/
output
MUX
and
buffers
DQ[7:0]
DQ[15:8]
Refresh configuration
register (RCR)
Bus configuration
register (BCR)
CE#
WE#
OE#
CLK
ADV#
CRE
WAIT
LB#
UB#
Control
logic
Note:
Functional block diagrams illustrate simplified device operation. See the ball description
table and timing diagrams for detailed information.
PDF: 09005aef82e41987 / Source: 09005aef82e419a5
8mb_4mb_burst_cr1_0_p22z__2.fm - Rev. C 4/ 08 EN
5
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2007 Micron Technology, Inc. All rights reserved.
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
