Hwaling Technology Co., Ltd.



Product Name : 128Mb (2Mx4Banks×16) DDR2 SDRAM

Item No. : H2A31281656B


The H2A31281656B is a 128M bits DDR2 SDRAM, organized as 2,097,152words x 4 banks x 16 bits. The -25 grade parts are compliant to the DDR2 800 (6-6-6) specification . The -3 grade parts is compliant to the DDR2-667 (5-5-5) specification.
JEDEC specifications require the refresh rate to double when TCASE exceeds +85°C; this also requires use of the high-temperature self refresh option. Additionally, ODT resistance and the input/output impedance must be derated when TCASE is < 0°C or > +85°C. All of the control and address inputs are synchronized with a pair of externally supplied differential clocks. Inputs are latched at the cross point of differential clocks (CLK rising and CLK falling). All I/Os are synchronized with a single ended DQS or differential DQS- DQS pair in a source synchronous fashion.
H2A31281656B _DDR2_8Mx16 (1.8 MB)
  • Power Supply: VDD, VDDQ = 1.8 V ± 0.1V
  • Double Data Rate architecture: two data transfers per clock cycle
  • Burst Length: 4 and 8
  • Bi-directional, differential data strobes (DQS and DQS ) are transmitted / received with data
  • Edge-aligned with Read data and center-aligned with Write data
  • DLL aligns DQ and DQS transitions with clock
  • Differential clock inputs (CLK and CLK )
  • Data masks (DM) for write data
  • Commands entered on each positive CLK edge, data and data mask are referenced to both edges of DQS
  • Posted CAS programmable additive latency supported to make command and data bus efficiency
  • Read Latency = Additive Latency plus CAS Latency (RL = AL + CL)
  • Off-Chip-Driver impedance adjustment (OCD) and On-Die-Termination (ODT) for better signal quality
  • Auto-precharge operation for read and write bursts
  • Auto Refresh and Self Refresh modes
  • Precharged Power Down and Active Power Down
  • Write Data Mask
  • Write Latency = Read Latency - 1 (WL = RL - 1)
  • Interface: SSTL_18
  • Packaged in TFBGA 84 Ball (8X12.5 mm2 ), using Lead free materials with RoHS compliant