IS43R32800B-6BLI ISSI, Integrated Silicon Solution Inc, IS43R32800B-6BLI Datasheet - Page 22

• Manufacturer Part Number: IS43R32800B-6BLI
• Manufacturer: ISSI, Integrated Silicon Solution Inc
• Type: DDR SDRAMr

Specifications of IS43R32800B-6BLI

• Organization: 8Mx32
• Density: 256Mb
• Address Bus: 14b
• Access Time (max): 700ps
• Maximum Clock Rate: 333MHz
• Operating Supply Voltage (typ): 2.5V
• Operating Temp Range: -40C to 85C
• Operating Supply Voltage (max): 2.7V
• Operating Supply Voltage (min): 2.3V
• Pin Count: 144
• Mounting: Surface Mount
• Operating Temperature Classification: Industrial
• Lead Free Status / Rohs Status: Compliant

IS43R32800B
22
EXTENDED MODE REGISTER
The Extended Mode Register controls functions beyond those controlled by the Mode Register; these additional
functions include DLL enable/disable, output drive strength selection (optional). These functions are controlled via
the bits shown in Figure EXTENDED MODE REGISTER.
The Extended Mode Register is programmed via the MODE REGISTER SET command (with BA0 = 1 and BA1 =
0) and will retain the stored information until it is programmed again or the device loses power. The Extended Mode
Register must be loaded when all banks are idle and no bursts are in progress, and the controller must wait the
specified time before initiating any subsequent operation. After tMRD from a MRS command the DDR SDRAM is
ready for a new command. Violating either of these requirements will result in unspecified operation.
DLL Enable/Disable
The DLL must be enabled for normal operation. DLL enable is required during power-up initialization, and upon
returning to normal operation after having disabled the DLL for the purpose of debug or evaluation (upon exiting
Self Refresh Mode, the DLL is enabled automatically). Any time the DLL is enabled a DLL Reset must follow and
200 clock cycles must occur before any executable command can be issued.
Output Drive Strength
The normal drive strength for all outputs is specified to be SSTL_2, Class II. The ISSI DDR SDRAM also supports a
weak driver strength option, intended for lighter load and/or point-to-point environments.
BA 1 B A0 A11 A 10 A9
0
1
0
EXTENDED MODE REGISTER
0
0
A8
0
A7
0
A6
0
A5
0
A4
0
A3
0
A2
0
Integrated Silicon Solution, Inc. — www.issi.com
A1
DS
Strength
Drive
A0
DD
DL L D isable
0
1
A11-A0
CL K
/CLK
/CS
/RAS
/CAS
/WE
BA 0
BA 1
0
1
Normal
Weak
DLL Disable
DLL Enable
V
Rev. 00D
03/19/08