Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

How about decreasing vccint?

I would like to decrease power consumption of cylcone III . I made test to low down 1.2v vccint to 1.0v, which save almost 60mw and works well.

My question is,is this normal? I thought if the vatalage is not enough ，it will affect conduction and will consume more power.Thank you!

3 Replies

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

    You hardly won't get a specification for VCCINT operation outside the range of 1.15 to 1.25. Please notice, that VCCINT is monitored by the POR reset circuit. The actual threshold may vary between individual devices and with temperature. So - except for experimental purposes - don't do it.

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

    Have you considered using Cyclone IV E instead? The Cyclone IV E is extremely similar to Cyclone III and it comes in two voltage variations, 1.2V (speed grade 6, 7 or 8) and 1.0V (speed grade 8L or 9L).

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

    --- Quote Start ---

    Have you considered using Cyclone IV E instead? The Cyclone IV E is extremely similar to Cyclone III and it comes in two voltage variations, 1.2V (speed grade 6, 7 or 8) and 1.0V (speed grade 8L or 9L).

    --- Quote End ---

    Thanks.But here we need a long delivery for the new IV series.Do you mean if we use Cyclone IV E (speed grade 8L or 9L) ,can decrease power consumption while also decreaseing the speed?