k4t51163qi-hpf7 Samsung Semiconductor, Inc., k4t51163qi-hpf7 Datasheet - Page 42

• Manufacturer Part Number: k4t51163qi-hpf7
• Description: 512mb I-die Ddr2 Sdram
• Manufacturer: Samsung Semiconductor, Inc.

44. For tAOFD of DDR2-667/800, the 1/2 clock of nCK in the 2.5 x nCK assumes a tCH(avg), average input clock HIGH pulse width of 0.5 relative to
K4T51163QI
For example, if an input clock has a worst case tCH(avg) of 0.48, the tAOF,min should be derated by subtracting 0.02 x tCK(avg) from it, whereas if an
Note that these deratings are in addition to the tAOF derating per input clock jitter, i.e. tJIT(duty) and tERR(6-10per). However tAC values used in the
tCK(avg). tAOF,min and tAOF,max should each be derated by the same amount as the actual amount of tCH(avg) offset present at the DRAM input
with respect to 0.5.
input clock has a worst case tCH(avg) of 0.52, the tAOF,max should be derated by adding 0.02 x tCK(avg) to it. Therefore, we have;
equations shown above are from the timing parameter table and are not derated. Thus the final derated values for tAOF are;
tAOF,min(derated) = tAC,min - [0.5 - Min(0.5, tCH(avg),min)] x tCK(avg)
tAOF,max(derated) = tAC,max + 0.6 + [Max(0.5, tCH(avg),max) - 0.5] x tCK(avg)
tAOF,min(derated) = Min(tAC,min, tAC,min - [0.5 - tCH(avg),min] x tCK(avg))
tAOF,max(derated) = 0.6 + Max(tAC,max, tAC,max + [tCH(avg),max - 0.5] x tCK(avg))
where tCH(avg),min and tCH(avg),max are the minimum and maximum of tCH(avg) actually measured at the DRAM input balls.
tAOF,min(derated_final) = tAOF,min(derated) + { - tJIT(duty),max - tERR(6-10per),max }
tAOF,max(derated_final) = tAOF,max(derated) + { - tJIT(duty),min - tERR(6-10per),min }
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Industrial
Rev. 1.0 August 2009
DDR2 SDRAM