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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>atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/developer/tools-software/tools/f/keil-forum/24419/atmega16-16pu-compatible-7-segment-led-driver</link><description> 
hello all, I am a newbee to embedded field.I need some good
suggetions and details regarding LED driver-ic.I want to know which
LED driver is suitable(or)compatible for atmega16-16pu mu-c and about
the shift register IC that is used in a LED.please</description><dc:language>en-US</dc:language><generator>Telligent Community 10</generator><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/142116?ContentTypeID=1</link><pubDate>Sun, 05 Oct 2008 15:36:18 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:9dd30372-308c-4442-87af-ac54426e3d51</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
If you post on any forum I read, I&amp;#39;m likely to respond.&lt;/p&gt;

&lt;p&gt;
But I don&amp;#39;t do private consultancy on the net. I have enough work
as it is.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/138923?ContentTypeID=1</link><pubDate>Sun, 05 Oct 2008 15:25:54 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:7890a0ff-336b-4526-95d8-566aed065542</guid><dc:creator>erik  malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
SITI 2221A and smilar offerings from Allegro, Rohm and more,&lt;/p&gt;

&lt;p&gt;
Erik&lt;/p&gt;

&lt;p&gt;
STILL, &lt;b&gt;this is the wrong place&lt;/b&gt; for ATmega references, where
does Keil come in?.&lt;/p&gt;

&lt;p&gt;
Erik&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/130376?ContentTypeID=1</link><pubDate>Sun, 05 Oct 2008 04:14:03 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:0481ce6c-3935-4908-a53b-cf9506eb8d4c</guid><dc:creator>Aloe Sree</dc:creator><description>&lt;p&gt;&lt;p&gt;
dear per, thanks for replying me.could I contact you further if I
got any doubts in the future regarding embedded.reply.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/124969?ContentTypeID=1</link><pubDate>Sun, 05 Oct 2008 03:09:17 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:5cdc6386-9e46-454a-9ac8-d905a2ec85a6</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
Are you shifting (no pun intended) question now?&lt;/p&gt;

&lt;p&gt;
Are you switching the question from LED drive chips to standard
shift registers? A normal shift register does not contain any logic
to control the drive current. If you use a normal shift register (for
example with 5V output) then you need to burn a significant
percentage of the voltage over a series resistor just to handle the
variances in the Vf of the individual diodes.&lt;/p&gt;

&lt;p&gt;
Multiplexing may work when you light individual diodes in an X/Y
matrix. When you have multi-diode segments then you either do need a
current-controlled driver, or you need to be able to drive the
individual diodes in the segment one-by-one or you need that the
diodes in the segment are in series and that you have high enough
drive voltage so you still have a significant amount of voltage to
burn over a series resistor.&lt;/p&gt;

&lt;p&gt;
Back to you again: Exactly what work have _you_ done. Have you at
least once tried Google for LED driver chips and taken a closer look
at some of the drivers? It is important that _you_ spend time
learning exactly how driver chips works. The quickest way is to
browse through the datasheets for 3-5 different chips. That would
give you ideas. That would also give you the background knowledge to
come back and ask specific questions about advantages of different
concepts. Requesting that &amp;quot;the net&amp;quot; should do all your homework is
not really a working solution. A 80-digit display board is expensive.
You really own it to yourself and whoever chips (still no pun
intended) in the money to make sure that _you_ learn how to drive
diodes, and that _you_ know enough to be able to motivate why _you_
selected a specific chip - even if that driver chip was recommended
on a web forum.&lt;/p&gt;

&lt;p&gt;
Why? It is _you_ who will have to explain why it doesn&amp;#39;t work, or
why the display burns out diodes, if you make an incorrect
design.&lt;/p&gt;

&lt;p&gt;
I mentioned multi-LED display segments earlier. But I still don&amp;#39;t
know if there are one, two, three, four, ... diodes/segment. Or if
the diodes have a common anode. Or if they have a common cathode. Or
if they are in series... On the web, you may get an example of a
perfect LED driver. But without the knowledge about how the LED
segments are built, that LED driver may still be unusable - even if
it is a golden-edition super-duper LED driver. Only you have the full
information about the requirements. The only thing people on this -
or other forums - can suggest is if the LED driver works with your,
or any other, uC with a specific signal level on the I/O pins.&lt;/p&gt;

&lt;p&gt;
There are other important criteria too. How expensive is the
driver - and does the cost matter, compared to the cost of the other
parts in the project. Will the driver chip be available in your part
of the world? How many driver chips do you nead, and what lead times
can you accept for such a quantity? Are any second-sources available?
Expected life-time of the product? Any mounting requirements? Most
probably RoHS. ...&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/114304?ContentTypeID=1</link><pubDate>Sun, 05 Oct 2008 02:38:16 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:514c9458-16dd-466a-a35c-9c841044ddf4</guid><dc:creator>Aloe Sree</dc:creator><description>&lt;p&gt;&lt;p&gt;
I too have a thought of using shift register to drive all these in
a multiplexed passion,tell me which IC(s) is better so that it could
be used for shift register and multiplexer&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/101146?ContentTypeID=1</link><pubDate>Sun, 05 Oct 2008 02:30:28 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:dad35b74-c93a-4419-b27b-630e8838b5f3</guid><dc:creator>ImPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
Read lesson 2 again.&lt;/p&gt;

&lt;p&gt;
If the LED driver has compatible signal levels, then it will be
compatible.&lt;/p&gt;

&lt;p&gt;
In this case - since you have quite a lot of LEDs - you should
look at either a multiplexed solution, but better a LED driver with
shift-register and current control. Current control is extra
important since I have to assume that there are multiple LED in each
segment of these 7-segment digits. A multiplexed display requires
that the individual diodes are very closely matched to make sure that
they get an uniform intensity and that some LEDs are not burned to
cinders.&lt;/p&gt;

&lt;p&gt;
Responder #1 - Erik Malund - is probably ready to supply a number
of favourite driver chips, since working with display boards is what
he does for a living.&lt;/p&gt;

&lt;p&gt;
What solutions have you looked at yourself?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/101154?ContentTypeID=1</link><pubDate>Sun, 05 Oct 2008 02:18:02 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:e00c1754-ebf7-4c53-b0af-b9494c7284a8</guid><dc:creator>Aloe Sree</dc:creator><description>&lt;p&gt;&lt;p&gt;
Dear per westermark, thankyou for replying my message.I want to
drive a LED display board that have 7 segment LEDs in both 2 inches
and 1 inch length. 2 inch LEDs in upper part of the board and 1 inch
LEDs on the lower side.There is a provision for digital clock,that
would come in between 2 and 1 inch LEDs on the sides.Total LEDs
constitutes 80 digits.I am using atmega16 to send signals to all
these LEDs.I want to what type of driver that I should have to use
that is compatible for Atmega16 to drive all these LEDs.Is this info
is enough to you? kindly reply.&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/89302?ContentTypeID=1</link><pubDate>Fri, 03 Oct 2008 13:15:19 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:b3bd3f2e-bc40-4c79-b85d-bbcb0ff5c04d</guid><dc:creator>Andy Neil</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;a href="http://www.avrfreaks.net/"&gt;http://www.avrfreaks.net/&lt;/a&gt;&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/89303?ContentTypeID=1</link><pubDate>Fri, 03 Oct 2008 10:38:36 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:9be9e341-90c1-4553-bab6-487a1c02f9ff</guid><dc:creator>edPer Westermark</dc:creator><description>&lt;p&gt;&lt;p&gt;
Second lesson:&lt;/p&gt;

&lt;p&gt;
If the processor has 3.3V signaling, then most peripherial chips
with 3.3V signal levels are compatible.&lt;/p&gt;

&lt;p&gt;
If the processor hsa 5V signaling, then most peripherial chips
with 5V signal levels are compatible.&lt;/p&gt;

&lt;p&gt;
Third lesson:&lt;/p&gt;

&lt;p&gt;
It isn&amp;#39;t enough to say that you need a LED driver IC. You also
have to describe what problem you are going to solve. Are you going
to drive a number of high-intensity LED for illumination? Or are you
going to build a full-color 720x480 pixel LED TV? Or something in
between?&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item><item><title>RE: atmega16-16PU compatible 7 segment LED driver</title><link>https://community.arm.com/thread/52569?ContentTypeID=1</link><pubDate>Fri, 03 Oct 2008 10:24:03 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:80c0b870-53a4-43eb-a020-5106607bb47d</guid><dc:creator>erik  malund</dc:creator><description>&lt;p&gt;&lt;p&gt;
&lt;i&gt;I am a newbee to embedded field&lt;/i&gt;&lt;br /&gt;
first lesson:&lt;br /&gt;
Keil does not support atmega and thus you are in the wrong place&lt;/p&gt;

&lt;p&gt;
the atmegas are discussed in a place named something like
avrphreaks&lt;/p&gt;

&lt;p&gt;
Erik&lt;/p&gt;
&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>