MT48H8M32LFB5-75 IT:H Micron Technology Inc, MT48H8M32LFB5-75 IT:H Datasheet - Page 49

• Manufacturer Part Number: MT48H8M32LFB5-75 IT:H
• Description: DRAM Chip Mobile SDRAM 256M-Bit 8Mx32 1.8V 90-Pin VFBGA Tray
• Manufacturer: Micron Technology Inc
• Type: Mobile SDRAMr

Specifications of MT48H8M32LFB5-75 IT:H

• Density: 256 Mb
• Maximum Clock Rate: 133 MHz
• Package: 90VFBGA
• Address Bus Width: 14 Bit
• Operating Supply Voltage: 1.8 V
• Maximum Random Access Time: 8|6 ns
• Operating Temperature: -40 to 85 °C
• Format - Memory: RAM
• Memory Type: Mobile SDRAM
• Memory Size: 256M (8Mx32)
• Speed: 133MHz
• Interface: Parallel
• Voltage - Supply: 1.7 V ~ 1.95 V
• Package / Case: 90-VFBGA
• Organization: 8Mx32
• Address Bus: 14b
• Access Time (max): 8/6ns
• Operating Supply Voltage (typ): 1.8V
• Package Type: VFBGA
• Operating Temp Range: -40C to 85C
• Operating Supply Voltage (max): 1.95V
• Operating Supply Voltage (min): 1.7V
• Supply Current: 100mA
• Pin Count: 90
• Mounting: Surface Mount
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 18: Random READ Accesses
PDF: 09005aef834c13d2
256mb_mobile_sdram_y36n.pdf - Rev. I 11/09 EN
Note:
Command
Command
Data from any READ burst can be truncated with a subsequent WRITE command, and
data from a fixed-length READ burst can be followed immediately by data from a
WRITE command (subject to bus turnaround limitations). The WRITE burst can be initi-
ated on the clock edge immediately following the last (or last desired) data element
from the READ burst, provided that I/O contention can be avoided. In a given system
design, there is a possibility that the device driving the input data will go Low-Z before
the DQ go High-Z. In this case, at least a single-cycle delay should occur between the
last read data and the WRITE command.
The DQM input is used to avoid I/O contention, as shown in Figure 19 (page 50) and
Figure 20 (page 51). The DQM signal must be asserted (HIGH) at least two clocks prior
to the WRITE command (DQM latency is two clocks for output buffers) to suppress data-
out from the READ. After the WRITE command is registered, the DQ will go to High-Z
(or remain High-Z), regardless of the state of the DQM signal, provided the DQM was
active on the clock just prior to the WRITE command that truncated the READ com-
mand. If not, the second WRITE will be an invalid WRITE. For example, if DQM was
LOW during T4, then the WRITEs at T5 and T7 would be valid, and the WRITE at T6
would be invalid.
Address
Address
1. Each READ command can be issued to any bank. DQM is LOW.
CLK
CLK
DQ
DQ
T0
T0
READ
Bank,
READ
Bank,
Col n
Col n
CL = 2
T1
T1
READ
READ
Bank,
Bank,
Col a
Col a
256Mb: 16 Meg x 16, 8 Meg x 32 Mobile SDRAM
CL = 3
49
T2
T2
Bank,
Bank,
READ
READ
Col x
Col x
D
OUT
T3
T3
Micron Technology, Inc. reserves the right to change products or specifications without notice.
READ
Bank,
Col m
READ
Bank,
Col m
D
D
OUT
OUT
T4
T4
NOP
NOP
D
D
OUT
OUT
T5
T5
NOP
NOP
D
D
OUT
OUT
©2008 Micron Technology, Inc. All rights reserved.
T6
Don’t Care
READ Operation
NOP
D
OUT