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From: Joel on 29 Jan 2010 08:32
I've got eight 7-segment displays. I know I've multiplex four at once but
eight seems like a lot. It'd be slick to need just 16 pins. Can it be
done?

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From: Grant Edwards on 29 Jan 2010 09:14
On 2010-01-29, Joel <joelbenway(a)n_o_s_p_a_m.gmail.com> wrote:

> I've got eight 7-segment displays. I know I've multiplex four
> at once but eight seems like a lot. It'd be slick to need
> just 16 pins. Can it be done?

Yes.

--
Grant Edwards grante Yow! An Italian is COMBING
at his hair in suburban DES
visi.com MOINES!
From: JW on 29 Jan 2010 09:25
On Fri, 29 Jan 2010 07:32:12 -0600 "Joel"
<joelbenway(a)n_o_s_p_a_m.gmail.com> wrote in Message id:
<97udndywFsvBfv_WnZ2dnUVZ_u2dnZ2d(a)giganews.com>:

>I've got eight 7-segment displays. I know I've multiplex four at once but
>eight seems like a lot. It'd be slick to need just 16 pins. Can it be
>done?

Of course. Here's one for 16 digits:
http://www.maxim-ic.com/app-notes/index.mvp/id/3210
From: antedeluvian on 29 Jan 2010 13:13
>On Fri, 29 Jan 2010 07:32:12 -0600 "Joel"
><joelbenway(a)n_o_s_p_a_m.gmail.com> wrote in Message id:
><97udndywFsvBfv_WnZ2dnUVZ_u2dnZ2d(a)giganews.com>:
>
>>I've got eight 7-segment displays. I know I've multiplex four at once
but
>>eight seems like a lot. It'd be slick to need just 16 pins. Can it be
>>done?
>
>Of course. Here's one for 16 digits:
>http://www.maxim-ic.com/app-notes/index.mvp/id/3210
>

If you are looking for dedicated hardware also look at the ICM7218. It w2as
made by both Intersil and Maxim, but today...

If you are trying to do this as a roll your own- look up "charlieplexing"
on the Maxim web site and also EDN and Electronic Design. There was a
flurry of discussions recently and how to use the least number of bits.

I have a very old HP application book on optoelectronics (in electronic
format) that discusses this quite well. if you let me have an address, I
can try and figure out how to get the 120MB to you.

-Aubrey

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From: antedeluvian on 29 Jan 2010 14:29
>>On Fri, 29 Jan 2010 07:32:12 -0600 "Joel"
>><joelbenway(a)n_o_s_p_a_m.gmail.com> wrote in Message id:
>><97udndywFsvBfv_WnZ2dnUVZ_u2dnZ2d(a)giganews.com>:
>>
>>>I've got eight 7-segment displays. I know I've multiplex four at once
>but
>>>eight seems like a lot. It'd be slick to need just 16 pins. Can it be
>>>done?
>>
>>Of course. Here's one for 16 digits:
>>http://www.maxim-ic.com/app-notes/index.mvp/id/3210
>>
>
>If you are looking for dedicated hardware also look at the ICM7218. It
w2as
>made by both Intersil and Maxim, but today...
>
>If you are trying to do this as a roll your own- look up "charlieplexing"
>on the Maxim web site and also EDN and Electronic Design. There was a
>flurry of discussions recently and how to use the least number of bits.
>
>I have a very old HP application book on optoelectronics (in electronic
>format) that discusses this quite well. if you let me have an address, I
>can try and figure out how to get the 120MB to you.
>
>-Aubrey

You may want to check AN1216 and Application Brief D-0004 from Avago.

-Aubrey
>
>---------------------------------------
>Posted through http://www.EmbeddedRelated.com
>

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