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<?xml-stylesheet type="text/xsl" href="https://community.arm.com/utility/feedstylesheets/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/"><channel><title>dimming</title><link>https://community.arm.com/developer/tools-software/tools/f/keil-forum/31846/dimming</link><description> 
hi:friend 
i have a led project ,need linear dimming, use ARM K60N512VMD100 ADC
to control PWM dimming. 
the ADC is 0.5V-5V, pwm ratio 2% to 100%. step need greater than
200. 
if me use read table , the curve is not linear . 
have you one tell me ,how</description><dc:language>en-US</dc:language><generator>Telligent Community 10</generator><item><title>RE: dimming</title><link>https://community.arm.com/thread/140719?ContentTypeID=1</link><pubDate>Tue, 06 May 2014 15:05:34 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:c4a31273-d384-4203-b793-8a0bf3a20240</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;i have a led project ,need linear dimming&lt;/i&gt;&lt;br /&gt;
more than a million LEDs have are dimmed relative to ambient by my
code&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/137124?ContentTypeID=1</link><pubDate>Tue, 06 May 2014 08:38:11 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:54415045-a9a1-49ba-afc7-3ce2319e4740</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
Yes, when the quotient between ambient and LED output is the same,
the eyes will be happy as long as we are within the supported
adjustment range of the eyes. Cameras would have a hard time
capturing data if it wasn&amp;#39;t enough to adjust aperture/time/ISO to
adjust the light level of all parts of the photo with the same number
of stops and have the viewer accept the capture.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/128569?ContentTypeID=1</link><pubDate>Tue, 06 May 2014 07:34:19 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:49bf704d-ef95-4636-821b-3c1110e537f0</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
if you reduce ambient, the eye &amp;#39;likes&amp;#39; you to reduce your sign or
whatever by the same percentage&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/120316?ContentTypeID=1</link><pubDate>Tue, 06 May 2014 06:07:09 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:88a26637-6a38-453b-912e-12b116f851a0</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
&amp;quot;correct; however the &amp;#39;percieved&amp;#39; intensity vs ambient is.&amp;quot;&lt;/p&gt;

&lt;p&gt;
Not really sure I understand what you mean with that.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/107663?ContentTypeID=1</link><pubDate>Tue, 06 May 2014 05:57:36 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:588208d9-5976-4572-b218-f74a13242555</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;But the human eye&amp;#39;s perception is not?&lt;/i&gt;&lt;br /&gt;
correct; however the &amp;#39;percieved&amp;#39; intensity vs ambient is.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/107659?ContentTypeID=1</link><pubDate>Tue, 06 May 2014 00:39:35 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:c58f5911-a0db-4452-a014-7299881c6aa7</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
No - most of our senses requires exponentially stronger
stimuli.&lt;/p&gt;

&lt;p&gt;
So to dim display in the dark needs to be very, very, very much
weaker than a strong display in daylight.&lt;/p&gt;

&lt;p&gt;
I have 10000 intensity steps in the displays I have programmed.
And that is still not really dark when viewed in a dark room.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/93182?ContentTypeID=1</link><pubDate>Tue, 06 May 2014 00:07:40 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:4a2e8cfa-a12d-4c47-8e91-8561ab1a7f43</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;&amp;quot;what curve LED intensity vs pulse width is pretty
linear&amp;quot;&lt;/i&gt;&lt;/p&gt;

&lt;p&gt;
But the human eye&amp;#39;s &lt;b&gt;perception&lt;/b&gt; is not?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/107664?ContentTypeID=1</link><pubDate>Mon, 05 May 2014 23:23:13 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:840f7e9f-254c-488e-938c-5ffc3ce709aa</guid><dc:creator>jamen lamen</dc:creator><description>&lt;p&gt;&lt;p&gt;
friend-&amp;gt;thanks&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/93180?ContentTypeID=1</link><pubDate>Sat, 03 May 2014 05:54:25 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:018ec4c8-8498-4d3f-98d7-fcfd75815d39</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;is the ARM powerful for the job,&lt;/i&gt;&lt;br /&gt;
the above can be done with any processor (8051 to pentium) that has
an ADC and PWM&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: dimming</title><link>https://community.arm.com/thread/62785?ContentTypeID=1</link><pubDate>Sat, 03 May 2014 05:50:30 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:7650c59e-4b09-4b48-b1aa-99922480056d</guid><dc:creator>&amp;#178;erik malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;the curve is not linear&lt;/i&gt;&lt;br /&gt;
what curve LED intensity vs pulse width is pretty linear, I have
worked 10+ years with LED (dimming) and never had to &amp;#39;correct&amp;#39;&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>