IS43/46DR81280A, IS43/46DR16640A  

Integrated Silicon Solution, Inc. – www.issi.com –

1

Rev. D, 08/30/2011

1Gb (x8, x16) DDR2 SDRAM

FEATURES 

 Clock frequency up to 400MHz 

 8 internal banks for concurrent operation 

 4‐bit prefetch architecture 

 Programmable CAS Latency: 3, 4, 5, 6 and 7 

 Programmable Additive Latency: 0, 1, 2, 3, 4, 5 

and 6 

 Write Latency = Read Latency‐1 

 Programmable Burst Sequence: Sequential or 

Interleave 

 Programmable Burst Length: 4 and 8 

 Automatic and Controlled Precharge Command 

 Power Down Mode 

 Auto Refresh and Self Refresh 

 Refresh Interval: 7.8 s (8192 cycles/64 ms) 

 OCD (Off‐Chip Driver Impedance Adjustment) 

 ODT (On‐Die Termination) 

 Weak Strength Data‐Output Driver Option 

 Bidirectional differential Data Strobe (Single‐

ended data‐strobe is an optional feature) 

 On‐Chip DLL aligns DQ and DQs transitions with 

CK transitions 

 DQS# can be disabled for single‐ended data 

strobe 

 Read Data Strobe supported (x8 only) 

 Differential clock inputs CK and CK# 

 VDD and VDDQ = 1.8V ± 0.1V 

 PASR (Partial Array Self Refresh) 

 SSTL_18 interface 

 tRAS lockout supported 

 Operating temperature: 

105°C)

 

OPTIONS  

 

 Configuration: 

 128Mx8 (16M x 8 x 8 banks) 

 64Mx16 (8M x 16 x 8 banks)  

 Package: 

 60‐ball TW‐BGA for x8 

 84‐ball TW‐BGA for x16 

 

ADDRESS TABLE 

Parameter

128Mx8 

64Mx16

Row Addressing

A0‐A13 

A0‐A12

Column Addressing

A0‐A9 

A0‐A9

Bank Addressing

BA0‐BA2 

BA0‐BA2

Precharge Addressing

A10 

A10

Clock Cycle Timing 

 

‐37C 

‐3D 

‐25E 

‐25D 

Units 

Speed Grade 

DDR2‐533C 

DDR2‐667D

DDR2‐800E

DDR2‐800D  

CL‐tRCD‐tRP 

4‐4‐4 

5‐5‐5

6‐6‐6

5‐5‐5

tCK 

tCK (CL=3) 

5 

5

5

5

ns 

tCK (CL=4) 

3.75 

3.75

3.75

3.75

ns 

tCK (CL=5) 

3.75 

3

3

2.5

ns 

tCK (CL=6) 

3.75 

3

2.5

2.5

ns 

tCK (CL=7) 

3.75 

3

2.5

2.5

ns 

Frequency (max) 

266 

333

400

400

MHz 

Note: The ‐37C device specification is shown for reference only. 

SEPTEMBER 2011 

Copyright © 2011 Integrated Silicon Solution, Inc. All rights reserved. ISSI reserves the right to make changes to this specification and its products at any time

without notice. ISSI assumes no liability arising out of the application or use of any information, products or services described herein. Customers are advised to

obtain the latest version of this device specification before relying on any published information and before placing orders for products.

Integrated Silicon Solution, Inc. does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can

reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such

applications unless Integrated Silicon Solution, Inc. receives written assurance to its satisfaction, that:

a.) the risk of injury or damage has been minimized;

b.) the user assume all such risks; and

c.) potential liability of Integrated Silicon Solution, Inc is adequately protected under the circumstances