Lowest power 32-bit MCU with PCI, SDRAM?

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I have seen plenty of ARM MCUs out there with impressive power
consumption, but a very few offer SDRAM, and only one has PCI
interface.

The motorola types, Dragonball and coldfire have these features, but
are an order of magnitude more expensive on power. What is the least
power consuming 32-bit MCU with glueless SDRAM and PCI interfaces? I'd
prefer architectures that can use the PalmOS 4.0 or higher (ARM9 or
68k). I wonder if adding a PCI interface chip or SDRAM interface chip
to an ARM9 or even an ARM7 will take lower power than all current
offerings.

Re: Lowest power 32-bit MCU with PCI, SDRAM?
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Does it have to be ARM? Consider the PowerPC 405 or 440EP/GP series.

-->Neil



Re: Lowest power 32-bit MCU with PCI, SDRAM?
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Can be anything that runs Linux/NetBSD. Is the PPC lower on power than
the Dragonball series? I'm aiming for less than 100mW. Possible?

Re: Lowest power 32-bit MCU with PCI, SDRAM?
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An MPC870 @66MHz with 2 SDRAMs and some peripherals will require
approx. 2..3Watts. This PPC core has no PCI interface.

100mW sounds not possible for what you plan to do. If your application is
idle most of the time (say 99%) you can however look for a CPU with power-
saving sleep modes. This can reduce power over time significantly.

Yours
- Rene



Re: Lowest power 32-bit MCU with PCI, SDRAM?


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offerings.

Question is why you need PCI? PCI uses 50-60 pins
and toggles most of those pins at 33-66 MHz.
Does not sound like low power to me...

Most people building ARM will build a chip which contains
the things you normally put on PCI, and that will draw lower power.

If you need high speed connection to something,
the ARM options are typically USB or other serial interfaces.
You can run 100 Mbit per second on an Ethernet interface, so
if you have an FPGA, maybe you can connect directly to an MII?

--
Best Regards,
Ulf Samuelsson   ulf@a-t-m-e-l.com
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Re: Lowest power 32-bit MCU with PCI, SDRAM?
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low-cost computer. I'd be adding modules on it, like a soundcard,
various nics, and pcmcia options. High on the list is an embedded
graphics chip. I'm not sure if I can interconnect all these through
other busses, or afford their cores for FPGAs.

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I know PCI gets power hungry, but using a complete x86 system like the
STPC, Geode is more power demanding, and for reasons stated above, PCI
is necessary. So the aim is any good MCU with low power ratings
(nonx86), and PCI and SDRAM.

Re: Lowest power 32-bit MCU with PCI, SDRAM?
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An the whole stuff will require at least 3..4W, right? I thought the OP was
looking
for something in the 100mW range.

- Rene



Re: Lowest power 32-bit MCU with PCI, SDRAM?

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CPU

...

was

I think that the CPU uses about 60 mW (VccCORE) at 180 MHz but you can run
this at a much
lower speed if you want to so, you may be able to run it close to 10 mW.
Alternatively run at high speed, and then stop clock.
The AVR can handle events meanwhile at low power.
The CPU can turn off peripherals selectively, so anything you dont need only
draws leakage...

The SPI dataflash is not on the same bus as the SDRAM, so only the
capacitance of the SDRAM
(and the FPSLIC) is visible to the CPU. Most other CPUs put the Flash on the
same bus
as the SDRAM which increases the capacitance a lot, and thus also the power.
The dataflash can be powered down after U-boot has booted Linux.

If you are really out after low power, you can run the SDRAM at 1.8V while
the
rest of the I/O run at 3.3V. The Bus has its own I/O. The bus runs at 60
Mhz.

The Ethernet is going to be a Power Hog, due to some problem in the
implementation.
IIRC, th Ethernet does not power down unless the 50 MHz clock disappears,
which is doesnt.
I am pretty sure that an External PCI Ethernet is going to use a lot more
anyway.
For really low power it is best not used.

The AVR should use maybe 10 mW at 3.3V if you run it at slow speed.

The CPLD draws 40 mA @ 3V - terrible, but only when the SPI/Dataflash is
used.
If not, it powers down automatically to 5 uA.  Next year, bettewr parts
will reduce to < 20 mW. The SPI speed will affect power consutmpion
and if slower troughput is OK, then lower power results.

FPSLIC will use minimum 100 uA leakage, but the power consumption
of this will of course be depending on what is inside the FPGA.

No clue what the RS-232, CAN drivers or so will draw.
As long as you run USB only internally, you do not have to provide 100/500
mA.
Only what the other end needs.

You make your own judgement if this results in 3 Watts or if it is closer to
100 mW

--
Best Regards,
Ulf Samuelsson   ulf@a-t-m-e-l.com
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Re: Lowest power 32-bit MCU with PCI, SDRAM?
Hi,

take a look at the ALCHEMY Au1500 made by AMD on:
http://www.amd.com/us-en/ConnectivitySolutions/ProductInformation/0,,50_2330_6625,00.html

This has the features you want and is very low power.
Based on an enhanced MIPS core.
Pricing is in between 20 and 25 euros

Cheers,
    Lou

Re: Lowest power 32-bit MCU with PCI, SDRAM?
Have you seen the NetSilicon ARM's

regards JG

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Re: Lowest power 32-bit MCU with PCI, SDRAM?
On 31 Oct 2004 20:30:42 -0800, snipped-for-privacy@gmail.com (Ghazan Haider)

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Take a look at AMD's 32-bit Alchemy, moree specifically the Au1500
which has a PCI interface.....very low power.

Cheers,
    Lou

Re: Lowest power 32-bit MCU with PCI, SDRAM?
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interfaces?

Well, if it doesn't have to be an ARM, why not consider a MIPS RISC
device? VR4133 from NEC is quite interesting. It includes an SDRAM
interface, Ethernet Macs and PCI. Power consumption at 266 MHz is
200mA (typ.) at 1.5V and 30mA (typ.) at 3.3V. It will be less if you
run it a reduced speed. Performance costs power, so the question is
basically which kind of performance you have in mind for the 100mW
that you want to spend. And also look for on-chip memory or caches.
Accesses to external memory are very costly for the power budget.

Michael

Re: Lowest power 32-bit MCU with PCI, SDRAM?
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Now this looks VERY interesting. I'm not too bothered about power,
something like 100MIPS, or a 133MHz Pentium1 with 32mb ram is good.
The idea is a simplistic Linux based computer, but with the full array
of tools like web browser, office tools etc. I understand PCI takes
both power, and requires 3.3v at least. External ram will also be
costly, so I'll try to do one chip of 32mb, maybe at reduced clock,
and the MCU itself at 100MHz or so, possibly running at dynamic speed.

The device will hopefully be able to run with disposable batteries,
and should run for at least 10 hours straight (full use), unlike
current laptops. So the higher the power usage gets, the more
batteries I'll have to add, the less attractive it will seem compared
to a laptop. It will also kill my remote hope for a solar powered
802.11-run laptop.

The PCI is necessary. None of the MCUs have a good video device (3d
accelerated), none have 802.11a/b/g, few have pcmcia controller etc.
Best would be to have an x86-based chip, next ARM, next anything else
since the software support for ARM and x86, at least in Linux, is
good. This mips devices gives me a good alternative to look at beside
the x86 and arm, at the cost of wrestling with linux/netbsd to make
things go.

Re: Lowest power 32-bit MCU with PCI, SDRAM?

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This will become a problem for you since MIPS is not x86 compatible
and most 3D video drivers are binary only...

Andmost recent 3D boards have fans to remove heat...

I think you will have some trouble buying a good video board:
* for PCI
* with open source drivers
* low power consumption
* at a reasonable price

But an older ATI Radeon board could fit... (newer ones are not open source)

/RogerL

Re: Lowest power 32-bit MCU with PCI, SDRAM?
Guess some more homework is needed. If you plan to have a 3D
accelerator, have a look at that power consumption rather than the
main CPU. These things are compact heaters. Simplify you graphics,
have a look at the highend Sharp ARM microcontrollers. So let's assum
your graphics can be done with the embedded controller, the LH7A404,
ARM9 based micro might be your best bet.

Schwob

snipped-for-privacy@gmail.com (Ghazan Haider) wrote in message
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