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Altera_Forum
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17 years ago

stratix III with DDR2 temination

hi my design include stratix III device with 2 ddr2 hp core. each core is facing 5 DDR2 components when 1 of the 5 is for ECC. i looked at the termination schemes in AN408 and not found my ans...
Altera_Forum's avatar
Altera_Forum
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17 years ago

Well, the VTT power should be low impedance, both DC and AC. Low AC impedance is achieved by capacitors, for low DC impedance a termination regulator as the said LP2997 is the most simple solution. Even without DQ/DQS external termination, e. g. 0.5 A may be drawn at worst case, hardly to achieve with a resistive divider or a general purpose OP.