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Altera_Forum's avatar
Altera_Forum
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11 years ago

Can't power down HPCII DDR2, Cyclone III

I am trying to get the auto power-down function of the HPC II DDR2 controller to work. I'm trying to cut down static power in an older design, so if at all possible I don't want to bump the Quartus rev (9.1sp2).

The relevant settings are in the image below:

https://www.alteraforum.com/forum/attachment.php?attachmentid=8951

I get no decrease in static power at all. The DDR2 ram is a pair of Micron MT47H84M16-3ITH, configured as 64MBx32 @150MHz. The DDR2 works as memory.

(Note: I get the same results with Quartus 11.1sp2, although there are timing issues created I'd rather not deal with)

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    Apparently I want self-refresh off and user refresh on (but never requested). But even with nothing going on on the control lines to the RAM (all signals but clock inactive), I still don't see power down happening.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    Never mind. Termination issue. Needed to drive off-die termination based on power-down active indicator.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    Hi,

    Old post but can someone explain this issue to me? I am facing similar problem.

    Auto power-down function of the HPC II DDR2 has no effect in power consumption. When DDR2 controller is included in design board power consumption increases by 25% even when DDR2 is idling.

    I tried to hold controller in reset, disable clock also auto power down function from megawizard, nothing helps. Only when DDR2 controller is removed completely from top level file power consumption decreases.

    DDR2 controller is not required to work all the time, and I want to be able to completely shut it down to save power.