for a project I'm designing I am currently using a simple parallel Resistor Termination on the DDR2-Traces. But I'm wondering, what is the advantage of using a voltage regulator with serial-termination?
- Lower BOM/placement-cost?
- Lower power requirements?
- Something I'm totally missing?
My current design with 4 chips employs 54 terminations in total. This is done with 100 Ohm resistors. So we've got 1.8V/200Ohms = 9mA. 9mA*54 = 486mA plus reference voltage generation etc. it's more than 500mA unless my calculation is totally off. That results in nearly 1W of power dissipation just for the termination.
Are there any good guesstimates what the effect of an active regulation would be in a real world scenario?