IS43R32400D-5BL ISSI, Integrated Silicon Solution Inc, IS43R32400D-5BL Datasheet - Page 55

• Manufacturer Part Number: IS43R32400D-5BL
• Manufacturer: ISSI, Integrated Silicon Solution Inc
• Type: DDR SDRAMr

Specifications of IS43R32400D-5BL

• Organization: 4Mx32
• Density: 128Mb
• Address Bus: 14b
• Access Time (max): 700ps
• Maximum Clock Rate: 200MHz
• Operating Supply Voltage (typ): 2.6V
• Operating Temp Range: 0C to 70C
• Operating Supply Voltage (max): 2.7V
• Operating Supply Voltage (min): 2.5V
• Supply Current: 185mA
• Pin Count: 144
• Mounting: Surface Mount
• Operating Temperature Classification: Commercial
• Lead Free Status / RoHS Status: Compliant

IS43R32400D, IS43R16800D
REFRESH REQUIREMENTS
DDR SDRAM devices require a refresh of all rows in any 64ms(x16) or 32ms(x32). Each refresh is generated in one
of two ways: by an explicit AUTO REFRESH command, or by an internally timed event in SELF REFRESH mode.
Dividing the number of device rows into the rolling 64ms or 32ms interval defines the average refresh interval (tREFI),
which is a guideline to controllers for distributed refresh timing.
AUTO REFRESH
AUTO REFRESH command is used during normal operation of the DDR SDRAM. This command is non persistent, so
it must be issued each time a refresh is required.
The refresh addressing is generated by the internal refresh controller. The DDR SDRAM requires AUTO REFRESH
commands at an average periodic interval of tREFI.
Integrated Silicon Solution, Inc.
Rev. 00D
06/22/09
Notes:
* = ”Don’t Care”, if AP is HIGH at this point; AP must be HIGH if more than one bank is active (i.e., must precharge all active
PRE = PRECHARGE, ACT = ACTIVE, RA = Row Address, BA = Bank Address, AR = AUTOREFRESH
NOP commands are shown for ease of illustration; other valid commands may be possible after tRFC.
DM, DQ and DQS signals are all ”Don’t Care”/High--Z for operations shown
banks)
AUTO REFRESH command
55