Do DDR2 chips and controllers have on-die termination?

Question

I am going to try to interface a low-speed 8-bit DDR2 chip with an FPGA, and I've got some questions crucial to make it work:

Is that correct that there is on-die termination on both DDR2 memory and controllers (an Altera Cyclone 3 FPGA in my case), so no additional termination resistors are required?

A DDR2 Chip - As in a Dram IC, or a DDR *Card*, as in the kind of memory module you see in a desktop computer (which are not, and will never really be "chips", even if some uneducated people like to call them so)? — Connor Wolf, Mar 02 '11 at 07:25
Single DDR2 IC. Interfacing to whole DIMM is pretty hardcore for beginners :-) — BarsMonster, Mar 02 '11 at 09:02

score 3 · Accepted Answer · answered Mar 01 '11 at 16:20

3

Yes, all DDR2 chips have it on-board. It is a required part of the standard.

answered Mar 01 '11 at 16:20

Brian Carlton

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DDR2 is controlled by JEDEC, which has gratis standards, right? What is the number of the relevant standard? – Kevin Vermeer Mar 01 '11 at 20:00
I don't have the standard; check Micron's web site for DDR2 data sheets and application notes. – Brian Carlton Mar 02 '11 at 16:31
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JESD79-2F is the JEDEC standard number for DDR2. The chips must have an ODT pin which enables/disables on-board termination. – Fizz Jan 08 '15 at 01:31
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Also, you can control the strength: infinite-ohms, 75-ohms, and 150-ohms are required. Some chips support 50-ohms too. – lamont cranston Jul 07 '15 at 21:14

Do DDR2 chips and controllers have on-die termination?

1 Answers1