MT49H16M18CBM-25 Micron Technology Inc, MT49H16M18CBM-25 Datasheet - Page 36

• Manufacturer Part Number: MT49H16M18CBM-25
• Manufacturer: Micron Technology Inc
• Type: RLDRAMr

Specifications of MT49H16M18CBM-25

• Organization: 16Mx18
• Density: 288Mb
• Address Bus: 23b
• Maximum Clock Rate: 400MHz
• Operating Supply Voltage (typ): 1.8V
• Package Type: uBGA
• Operating Temp Range: 0C to 95C
• Operating Supply Voltage (max): 1.9V
• Operating Supply Voltage (min): 1.7V
• Supply Current: 779mA
• Pin Count: 144
• Mounting: Surface Mount
• Operating Temperature Classification: Commercial
• Lead Free Status / RoHS Status: Compliant

AUTO REFRESH (AREF)
Figure 15:
PDF: 09005aef815b2df8/Source: 09005aef811ba111
288Mb_RLDRAM_II_SIO_Core2.fm - Rev. O 1/11 EN
AUTO REFRESH Command
AREF is used to perform a REFRESH cycle on one row in a specific bank. Because the row
addresses are generated by an internal refresh counter for each bank, the external
address balls are “Don’t Care.” The bank addresses must be provided during the AREF
command. The bank address is needed during the AREF command so refreshing of the
part can effectively be hidden behind commands to other banks. The delay between the
AREF command and a subsequent command to the same bank must be at least
Within a period of 32ms (
device, the RLDRAM requires 64K cycles at an average periodic interval of 0.49µs MAX
(actual periodic refresh interval is 32ms/8K rows/8 banks = 0.488µs). To improve effi-
ciency, eight AREF commands (one for each bank) can be posted to the RLDRAM at peri-
odic intervals of 3.9µs (32ms/8K rows = 3.90µs). Figure 28 on page 51 illustrates an
example of a refresh sequence.
ADDRESS
ADDRESS
BANK
WE#
REF#
CK#
CS#
CK
DON’T CARE
BA
288Mb: x18 2.5V V
t
REF), the entire device must be refreshed. For the 288Mb
39
Micron Technology, Inc., reserves the right to change products or specifications without notice.
EXT
, 1.8V V
DD
, HSTL, SIO, RLDRAM II
©2003Micron Technology, Inc. All rights reserved.
Commands
t
RC.