I have a MC68000 accelerator card for the Apple that uses the Mostek DRAM MK4564N15
A 64M by 1 bit. Is the 4164-15 a drop-in replacement? Or is there a place that still sells the MK4564N14 DRAMs?
Basically, I want to make sure if the 4164 is drop in pin-for-pin and internal functionality identical to the Mostek.
Hopefully someone on this site may have datasheets on both and/or knowledgeable to help.
No Jameco wouldn't carry this part. I checked anyway. The reason is that this DRAM was made in the early eighties by a now defunct company Mostek. Mostek went bamkrupt (or sold off) in the eighties.
I hope someone here have the knowledge about that Mostek part equivalence like the 4164-150 --also a 64k by 1 DRAM.
Oops! I meant to say: "I hope someone here HAS the knowledge of the Mostek part to recommend an equivalence.
Whats a wittle gwammer among fwiends? lol
I by no means am an authoritative source, but after this thread caught my eye I googled for a few minutes, and based on what I'm seeing I suspect that you should be able to swap the Mostek part for another "industry standard" 64kx1 NMOS DRAM, 150 ms or faster.
Here's a web page that's a copy of an old Mostek press release which says: "MK4564: This device is the industry standard for the 64K dynamic RAM..."
This website talking about an obscure rare species of Commodore says with regard to memory expansion "...The chips required were the once-standard 64K by 1-bit dynamics (4164, 4564, 4864 etc.) at around 150nS...."
Another commodore page suggesting direct equivalence.
I also found an eBay auction for the chips in question (which unfortunately I misplaced the URL to) saying they'd been pulled from a Commodore PCB and claiming the were "standard" 64kx1 DRAMs. (Unfortunately the auction was in Malaysia.)
So my wild guess is you're probably save using a different chip. But of course I assume no responsibility for things going "boom".
Tbanks for this information. I had tried to bring up some of those documents but got "server error". At the time of the MK4564, there were several flavors u of DRAM that offered special functions like on chip RAS address counter refresh cycles.. You didn't need a refresh counter on your PC board as long as you followed certain RAS/CAS strobing sequences. Do you remember those nibble read modes? or column read modes on DRAMs then. Those features just complicated which flavors worked and didn't upon swap-outs..
Anyway, I spoke with Rob at Unicorn Electronics, he says they'tr identical. ***CASE SETTLED***
Thanks again for your invaluable input.
i have 14 of the original chips .brand new never used.if you need them or know anybody who dose send me an e-mail: firstname.lastname@example.org
have a merry christmas and happynew year
billg eng/owner audiolabs