RE: RFC: detect and manage power cut on MLC NAND

From: Ricard Wanderlof <ricard.wanderlof@axis.com>
To: "Jeff Lauruhn (jlauruhn)" <jlauruhn@micron.com>
Cc: "Iwo Mergler" <Iwo.Mergler@netcommwireless.com>,
	"Qi Wang 王起 (qiwang)" <qiwang@micron.com>,
	"dedekind1@gmail.com" <dedekind1@gmail.com>,
	"Richard Weinberger" <richard@nod.at>,
	"Andrea Scian" <rnd4@dave-tech.it>,
	"Ricard Wanderlöf" <ricardw@axis.com>,
	mtd_mailinglist <linux-mtd@lists.infradead.org>
Subject: RE: RFC: detect and manage power cut on MLC NAND
Date: Thu, 26 Mar 2015 09:55:29 +0100	[thread overview]
Message-ID: <alpine.DEB.2.02.1503260954140.13892@lnxricardw1.se.axis.com> (raw)
In-Reply-To: <0D23F1ECC880A74392D56535BCADD7356B6CA7ED@NTXBOIMBX03.micron.com>

On Thu, 26 Mar 2015, Jeff Lauruhn (jlauruhn) wrote:

> Let me explain the read process a bit.  When we program and erase too, 
> we set a target value L0 and L1 in the case of SLC and we get a 
> ...
> registers a 0 for that cell.  The sense circuit is very simple because 
> there needs to be 2K of them so we can sense the whole page 
> simultaneously.  The type of circuitry required to measure an analog 
> value would make the die huge.  If it was possible, it would already be 
> designed in.

> Instead of measuring the cell voltage, it was easier to allow the end 
> user to move Vread to maybe compensate for the shift in distribution.

Makes perfect sense. Thanks for the response!

/Ricard
-- 
Ricard Wolf Wanderlöf                           ricardw(at)axis.com
Axis Communications AB, Lund, Sweden            www.axis.com
Phone +46 46 272 2016                           Fax +46 46 13 61 30