Re: SRAM with multiplexed bus

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Thanks for all the replies. I am aware of the PSD devices, but I just need
SRAM.
It indeed strange, there *seems* to be a market demand for these types of
SRAM. Heck, some companies are still making 8k x 8 and 32k x 8 chips for
small embedded applications. There must be quite a lot of these applications
using muxed buses.

Meindert



Re: SRAM with multiplexed bus
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  True, but it's also a tough market, and Latched EPROMS are not what
you'd call at critical mass. They still exist, and in small packages,
( like the 27C520 from Atmel & Winbond ( and Fairchild for a while ) )

  The 27LV1026 is a good example of what CAN be done with smarter-bus
memory.

  Dallas do have a CLK/RAM with 2-4-8K with ALE BUS, but that's not
what would be called a generic part.

  With the growth of DATA Flash, and the drive now to push up the
read bandwidth, multiplexed BUS would be a good solution.

-jg


Re: SRAM with multiplexed bus

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Do

It is not longer a good idea to use "Many mainstream  microcontrollers"  in
applications requiring
medium sized SRAMs, since the 0,18u and lower embedded flash processes
allows
you to cost effectively integrate 32-64 kB of SRAM.
The AT91SAM7S series will be available in
32kF+8kR,64kF+16kR, 128kF+32kR, 256kF+64kR etc.
Philips LPC has similar combinations, although the flash size seems to be
fixed to 128kB in most parts.

With low cost ARM toolsets around the corner it is maybe time to to move on
guys :-)

--
Best Regards
Ulf at atmel dot com
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Re: SRAM with multiplexed bus
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in

Let me see: my application requires appr. 6000-8000 units/year.
The Mega162 costs me 2.35 euro, the latch appr. 0.10 euro and the SRAM 0,75
euro. That adds up to 3.20 euro. I haven't had an offer for an ARM type
controller for that price yet.

Meindert



Re: SRAM with multiplexed bus
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be
0,75


3,20 Euro * 1,3 = = $4,16.
Might work for the AT91SAM7S64 w 16 kB.
If you can fit the latch in your design, why complain?

--
Best Regards,
Ulf Samuelsson   ulf@a-t-m-e-l.com
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Re: SRAM with multiplexed bus
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I know. After my post I remembered an e-mail I recently received from our
local distributor: 3.16 euro for the AT91SAM7S32 and 4.57 euro for the
AT91SAM7S64, both in 100 units. So that's a good and cheap solution.

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Well, I can fit it in, but the routing requires as much extra board space as
required by the latch and SRAM. And it leaves me no room for expansion of
the design. But these new ARM mcu's are just the solution I was looking for.
The moment they're available here in the Netherlands, I'll design them in.

Regards,
Meindert



Re: SRAM with multiplexed bus

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as

So having it integrated is worth some money then :-)

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No need to wait, the parts are sampling and there is a development board as
well..

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--
Best Regards
Ulf at atmel dot com
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Re: SRAM with multiplexed bus
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as

Well, if they're sampled right now, who will guarantee I can run production
in 4 weeks (we have very short development times in our small company :-)) ?

Meindert



Re: SRAM with multiplexed bus
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I read the datasheet briefly and I vaguely rember a post in this ng about
it: does the LPC have no form of code protection?

Meindert



Re: SRAM with multiplexed bus
snipped-for-privacy@NOcustomSPAMware.nl says...
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Yes and no.  The 2104, 2105 and 2106 variants to not.  AFAIK the rest do.

Robert

Re: SRAM with multiplexed bus
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be
about

I wonder how Philips is going to get some market share with this.....

Meindert



Re: SRAM with multiplexed bus
Hi Ulf,

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Just so you know, we are looking very hard at these parts in our
migration away from horrible legacy 8-bit micros. I'm trying to get
managerial permission to port one or two simple projects to ARM in
order to pave the way for other projects.

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We hate Philips :)

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Is there something new coming out soon? If you want to forward me any
info, you know my email address...

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