4 MEG x 16
ASYNC/PAGE/BURST CellularRAM MEMORY
BURST
CellularRAM
TM
Features
• Single device supports asynchronous, page, and
burst operations
• V
CC
, V
CC
Q Voltages
1.70V–1.95V V
CC
1.70V–3.30V V
CC
Q
• Random Access Time: 70ns
• 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: 39ns (4 clocks) @ 104 MHz
t
ACLK: 6.5ns @ 104 MHz
• Page Mode Read Access
Sixteen-word page size
Interpage read access: 70ns
Intrapage read access: 20ns
• Low Power Consumption
Asynchronous READ < 25mA
Intrapage READ < 15mA
Initial access, burst READ:
(39ns [4 clocks] @ 104 MHz) < 35mA
Continuous burst READ < 15mA
Standby: 120µA—standard
100µA—low-power option
Deep power-down < 10µA
• Low-Power Features
Temperature Compensated Refresh (TCR)
Partial Array Refresh (PAR)
Deep Power-Down (DPD) Mode
Options
• Configuration:
4 Meg x 16
V
CC
Core Voltage Supply: 1.8V
V
CC
Q I/O Voltage: 1.8V
• Package
54-ball VFBGA
54-ball VFBGA—Lead-free
• Timing
60ns access
70ns access
85ns access
Designator
MT45W4MW16B
MT45W4MW16BFB
Figure 1: 54-Ball VFBGA
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
A21
A16
DQ4
V
SS
DQ14
DQ13
A14
A15
DQ5
DQ6
DQ15
A19
A12
A13
WE#
DQ7
A18
A8
A9
A10
A11
A20
WAIT
CLK
ADV#
NC
NC
NC
Top View
(Ball Down)
Options
(continued)
• Frequency
66 MHz
80 MHz
104 MHz
• Standby power
Standard
Low-power
• Operating Temperature Range
Wireless (-30°C to +85°C)
Industrial (-40°C to +85°C)
Designator
6
8
1
1
None
L
WT
2
IT
1
FB
BB
1
-60
-70
-85
1
NOTE:
1. Contact factory.
2. -30°C exceeds the CellularRAM Workgroup 1.0
specification of -25°C.
Part Number Example:
MT45W4MW16BFB-708LWT
09005aef80be1fbd pdf/09005aef80be2036 zip
Burst CellularRAM_1.fm - Rev. E 11/04 EN
1
©2003 Micron Technology, Inc. All rights reserved.
4 MEG x 16
ASYNC/PAGE/BURST CellularRAM MEMORY
Table of Contents
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Part-Numbering Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Valid Part Number Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Device Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Power-Up Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Bus Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Asynchronous Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Page Mode READ Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Burst Mode Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Mixed-Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
WAIT Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
LB#/UB# Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Low-Power Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Standby Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Temperature Compensated Refresh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Partial Array Refresh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Deep Power-Down Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Configuration Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Access Using CRE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Software Access. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Bus Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Burst Length (BCR[2:0]) Default = Continuous Burst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Burst Wrap (BCR[3]) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Output Impedance (BCR[5]) Default = Outputs Use Full Drive Strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
WAIT Configuration (BCR[8]) Default = WAIT Transitions One Clock Before Data Valid/Invalid . . . . . . . . .20
WAIT Polarity (BCR[10]) Default = WAIT Active HIGH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Latency Counter (BCR[13:11]) Default = Three-Clock Latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Operating Mode (BCR[15]) Default = Asynchronous Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Refresh Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Partial Array Refresh (RCR[2:0]) Default = Full Array Refresh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Deep Power-Down (RCR[4]) Default = DPD Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Temperature Compensated Refresh (RCR[6:5]) Default = +85°C Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Page Mode Operation (RCR[7]) Default = Disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Timing Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Data Sheet Designation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
09005aef80be1fbd pdf/09005aef80be2036 zip
Burst CellularRAMTOC.fm - Rev. E 11/04 EN
2
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
4 MEG x 16
ASYNC/PAGE/BURST CellularRAM MEMORY
List of Figures
Figure 1:
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:
54-Ball VFBGA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Functional Block Diagram—4 Meg x 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Part Number Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Power-Up Initialization Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
READ Operation (ADV = LOW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
WRITE Operation (ADV = LOW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Page Mode READ Operation (ADV = LOW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Burst Mode READ (4-word burst) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Burst Mode WRITE (4-word burst) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Wired or WAIT Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Refresh Collision During READ Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Refresh Collision During WRITE Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Configuration Register WRITE in Asynchronous Mode Followed by READ ARRAY Operation . . . .15
Configuration Register WRITE in Synchronous Mode Followed by READ ARRAY Operation . . . . .16
Load Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Read Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Bus Configuration Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
WAIT Configuration (BCR[8] = 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
WAIT Configuration (BCR[8] = 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
WAIT Configuration During Burst Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Latency Counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Refresh Configuration Register Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Typical Refresh Current vs. Temperature (I
TCR
) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
AC Input/Output Reference Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Output Load Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Initialization Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Asynchronous READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Asynchronous READ Using ADV#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Page Mode READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Single-Access Burst READ Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
4-Word Burst READ Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
4-Word Burst READ Operation (with LB#/UB#) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
READ Burst Suspend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Continuous Burst READ Showing an Output Delay with BCR[8] = 0 for End-of-Row Condition . . .41
CE#-Controlled Asynchronous WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
LB#/UB#-Controlled Asynchronous WRITE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
WE#-Controlled Asynchronous WRITE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
Asynchronous WRITE Using ADV#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Burst WRITE Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Continuous Burst WRITE Showing an Output Delaywith BCR[8] = 0 for End-of-Row Condition . .47
Burst WRITE Followed by Burst READ. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Asynchronous WRITE Followed by Burst READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
Asynchronous WRITE Followed By Burst READ—ADV# LOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Burst READ Followed by Asynchronous WRITE (WE#-Controlled) . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Burst READ Followed by Asynchronous WRITE Using ADV#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Asynchronous WRITE Followed by Asynchronous READ—ADV# LOW. . . . . . . . . . . . . . . . . . . . . . . . .53
Asynchronous WRITE Followed by Asynchronous READ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
54-Ball VFBGA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
09005aef80be1fbd pdf/09005aef80be2036 zip
Burst CellularRAMLOF.fm - Rev. E 11/04 EN
3
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
4 MEG x 16
ASYNC/PAGE/BURST CellularRAM MEMORY
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:
Table 15:
Table 16:
Table 17:
Table 18:
Table 19:
Table 20:
Table 21:
Table 22:
Table 23:
Table 24:
Table 25:
Table 26:
Table 27:
Table 28:
Table 29:
Table 30:
Table 31:
Table 32:
Table 33:
Table 34:
Table 35:
Table 36:
Table 37:
Table 38:
Table 39:
Table 40:
Table 41:
Table 42:
Table 43:
Table 44:
Table 45:
Table 46:
VFBGA Ball Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Bus Operations—Asynchronous Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Bus Operations—Burst Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Sequence and Burst Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Latency Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
64Mb Address Patterns for PAR (RCR[4] = 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Electrical Characteristics and Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Maximum Standby Currents for Applying PAR and TCR Settings—64Mb . . . . . . . . . . . . . . . . . . . . . .26
Maximum Standby Currents for Applying PAR and TCR Settings—64Mb Low-Power . . . . . . . . . . .26
Deep Power-Down Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Output Load Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Asynchronous READ Cycle Timing Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Burst READ Cycle Timing Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Asynchronous WRITE Cycle Timing Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Burst WRITE Cycle Timing Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Initialization Timing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Asynchronous READ Timing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Asynchronous READ Timing Parameters Using ADV#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Asynchronous READ Timing Parameters—Page Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Burst READ Timing Parameters—Single Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Burst READ Timing Parameters—4-Word Burst . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Burst READ Timing Parameters—4-Word Burst with LB#/UB#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Burst READ Timing Parameters—Burst Suspend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Burst READ Timing Parameters—BCR[8] = 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Asynchronous WRITE Timing Parameters—CE#-Controlled. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Asynchronous WRITE Timing Parameters—LB#/UB#-Controlled . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Asynchronous WRITE Timing Parameters—WE#-Controlled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
Asynchronous WRITE Timing Parameters Using ADV#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Burst WRITE Timing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Burst WRITE Timing Parameters—BCR[8] = 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47
WRITE Timing Parameters—Burst WRITE Followed by Burst READ . . . . . . . . . . . . . . . . . . . . . . . . . . .48
READ Timing Parameters—Burst WRITE Followed by Burst READ . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
WRITE Timing Parameters—Async WRITE Followed by Burst READ . . . . . . . . . . . . . . . . . . . . . . . . . .49
READ Timing Parameters—Async WRITE Followed by Burst READ . . . . . . . . . . . . . . . . . . . . . . . . . . .49
Asynchronous WRITE Timing Parameters—ADV# LOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Burst READ Timing Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Burst READ Timing Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Asynchronous WRITE Timing Parameters—WE# Controlled. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
Burst READ Timing Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Asynchronous WRITE Timing Parameters Using ADV#. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
WRITE Timing Parameters—ADV# LOW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
READ Timing Parameters—ADV# LOW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
WRITE Timing Parameters—Async WRITE Followed by Async READ . . . . . . . . . . . . . . . . . . . . . . . . . .54
READ Timing Parameters—Async WRITE Followed by Async READ . . . . . . . . . . . . . . . . . . . . . . . . . . .54
09005aef80be1fbd pdf/09005aef80be2036 zip
Burst CellularRAMLOT.fm - Rev. E 11/04 EN
4
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
4 MEG x 16
ASYNC/PAGE/BURST CellularRAM MEMORY
Micron
CellularRAM™ products are high-speed,
CMOS PSRAM memories developed for low-power,
portable applications. The MT45W4MW16BFB is a
64Mb DRAM core device organized as 4 Meg 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 offerings.
To operate seamlessly on a burst Flash bus, Cellular-
RAM products incorporate a transparent self refresh
mechanism. The hidden refresh requires no additional
support from the system memory controller and has
no significant impact on device read/write perfor-
mance.
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 coun-
terpart on burst mode Flash devices. The refresh con-
General Description
figuration 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 cur-
rent consumption during self refresh. CellularRAM
products include three system-accessible mechanisms
used to minimize standby current. Partial array refresh
(PAR) limits refresh to only that part of the DRAM array
that contains essential data. Temperature compen-
sated refresh (TCR) is used to adjust the refresh rate
according to the case temperature. The refresh rate
can be decreased at lower temperatures to minimize
current consumption during standby. Deep power-
down (DPD) halts the refresh operation altogether and
is used when no vital information is stored in the
device. These three refresh mechanisms are accessed
through the RCR.
Figure 1: Functional Block Diagram—4 Meg x 16
A[21:0]
Address Decode
Logic
4,096K 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 truth table, ball descriptions, and
timing diagrams for detailed information.
09005aef80be1fbd pdf/09005aef80be2036 zip
Burst CellularRAM_2.fm - Rev. E 11/04 EN
5
Micron Technology, Inc., reserves the right to change products or specifications without notice.
©2003 Micron Technology, Inc. All rights reserved.
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