Xref: utzoo comp.sys.m88k:562 comp.arch:20112 Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!crdgw1!crdos1!davidsen From: davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) Newsgroups: comp.sys.m88k,comp.arch Subject: Re: ECL 88k, an old posting Message-ID: <3106@crdos1.crd.ge.COM> Date: 9 Jan 91 19:22:11 GMT References: Reply-To: davidsen@crdos1.crd.ge.com (bill davidsen) Followup-To: comp.sys.m88k Organization: GE Corp R&D Center, Schenectady NY Lines: 27 In article pcg@cs.aber.ac.uk (Piercarlo Grandi) writes: | | In comp.arch I had asked if anybody could explain why currently it seems | much more difficult to get ECL *microprocessors* in production, and gave | examples of several that looked promising and have faded into obscurity. Let me say a few things about this... there are a lot more problems packaging ECL relative to CMOS. That is, ECL tends to be high power and needs to be physically larger in most cases to keep temperatures under control. Larger means longer delays so design rules all change. Market demand for a high power chip(set) is low unless the performance is really excellent. And there's the second part, the CMOS just keeps getting faster. People keep saying that the cutoff on CMOS is so many MHz or size no smaller than so many microns, and the designers keep proving those aren't the limits. Seems to me HP had some CMOS FIFO's or something last year that ran at a few GHz. And several people have told me of CMOS with "4000 angstrom design rules." What is holding ECL back, then, is a combination of things which limit the instances in which it's cost effective. If you want a faster version of an existing processor, wait a year and the original vendor will sell you one, still in CMOS, smaller, faster, lower power, and cheaper per MIP. -- bill davidsen (davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen) VMS is a text-only adventure game. If you win you can use unix.