Any very low power SPI flash?

Hi, i am developing a battery (CR2032) powered device that must log a fe
sensors for a minimum of 3 months every minute but longer would be better
The duty cycle is very low. In order to save the data i will be using a
SPI flash (16Mb). I was comparing at Atmel and SST (Microchip) and SS
seems to have the lowest current consumption device (max 15uA at standby
but it is still a bit high compared to the microcontroller (MSP430 fo
instance) and other sensors. Acceptable but high. Does any one knows an
other SPI flash with lower idle current and reasonble availability?

Second.. does any one knows if there is any problem on powering the flas
directly from the battery? Just asking becouse if there is a problem i wil
have to use a boost converter (more costly and less power efficient).

Thank you!

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

On 05/13/2012 08:38 PM, Sink0 wrote:
> Hi, i am developing a battery (CR2032) powered device that must log a few
> sensors for a minimum of 3 months every minute but longer would be better.
> The duty cycle is very low. In order to save the data i will be using an
> SPI flash (16Mb). I was comparing at Atmel and SST (Microchip) and SST
> seems to have the lowest current consumption device (max 15uA at standby)
> but it is still a bit high compared to the microcontroller (MSP430 for
> instance) and other sensors. Acceptable but high. Does any one knows any
> other SPI flash with lower idle current and reasonble availability?
>
> Second.. does any one knows if there is any problem on powering the flash
> directly from the battery? Just asking becouse if there is a problem i will
> have to use a boost converter (more costly and less power efficient).

How about turning off the power to the flash when you're not using it ?

> other SPI flash with lower idle current and reasonble availability?
MSP430 with embedded Ferromagnetic RAM
(FRAM)http://www.ti.com/ww/en/mcu/fram_ult...=Other+OT+FRAM

or
MSP430 with external FRAM (info:
http://www.fujitsu.com/global/servic...echnical/fram/) in
conjuction with GP MOSFET (2N7002) to control power line to the FRAM.

--
StoneThrower
www.dgmicrosys.com

"Sink0" <sink00@n_o_s_p_a_m.gmail.com> wrote in message
news: ...
> Hi, i am developing a battery (CR2032) powered device that must log a few
> sensors for a minimum of 3 months every minute but longer would be better.
> The duty cycle is very low. In order to save the data i will be using an
> SPI flash (16Mb). I was comparing at Atmel and SST (Microchip) and SST
> seems to have the lowest current consumption device (max 15uA at standby)
> but it is still a bit high compared to the microcontroller (MSP430 for
> instance) and other sensors. Acceptable but high. Does any one knows any
> other SPI flash with lower idle current and reasonble availability?
>
> Second.. does any one knows if there is any problem on powering the flash
> directly from the battery? Just asking becouse if there is a problem i
> will
> have to use a boost converter (more costly and less power efficient).
>
> Thank you!
>
> ---------------------------------------
> Posted through http://www.EmbeddedRelated.com

>> other SPI flash with lower idle current and reasonble availability?
>MSP430 with embedded Ferromagnetic RAM
>(FRAM)http://www.ti.com/ww/en/mcu/fram_ult...=Other+OT+FRAM
>
>or
>MSP430 with external FRAM (info:
>http://www.fujitsu.com/global/servic...echnical/fram/
in
>conjuction with GP MOSFET (2N7002) to control power line to the FRAM.
>
>--
>StoneThrower
>www.dgmicrosys.com
>
>"Sink0" <sink00@n_o_s_p_a_m.gmail.com> wrote in message
>news: m...
>> Hi, i am developing a battery (CR2032) powered device that must log
few
>> sensors for a minimum of 3 months every minute but longer would b
better.
>> The duty cycle is very low. In order to save the data i will be usin
an
>> SPI flash (16Mb). I was comparing at Atmel and SST (Microchip) and SST
>> seems to have the lowest current consumption device (max 15uA a
standby)
>> but it is still a bit high compared to the microcontroller (MSP430 for
>> instance) and other sensors. Acceptable but high. Does any one know
any
>> other SPI flash with lower idle current and reasonble availability?
>>
>> Second.. does any one knows if there is any problem on powering th
flash
>> directly from the battery? Just asking becouse if there is a problem i
>> will
>> have to use a boost converter (more costly and less power efficient).
>>
>> Thank you!
>>
>> ---------------------------------------
>> Posted through http://www.EmbeddedRelated.com
>
>

I liked the power down idea, Very simple adn reduce to 1uA current due t
the Mosfet. FRAM devices got very low memory or bulky packages so not th
best solution for now. Any comment on powering a 2.7V flash from 3.0V coi
battery? Thank you!

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

[This followup was posted to comp.arch.embedded and a copy was sent to
the cited author.]

In article <>, sink00
@n_o_s_p_a_m.gmail.com says...
>
> >> other SPI flash with lower idle current and reasonble availability?
> >MSP430 with embedded Ferromagnetic RAM
> >(FRAM)http://www.ti.com/ww/en/mcu/fram_ult...=Other+OT+FRAM
> >
> >or
> >MSP430 with external FRAM (info:
> >http://www.fujitsu.com/global/servic...echnical/fram/)
> in
> >conjuction with GP MOSFET (2N7002) to control power line to the FRAM.
> >
> >--
> >StoneThrower
> >www.dgmicrosys.com
> >
> >"Sink0" <sink00@n_o_s_p_a_m.gmail.com> wrote in message
> >news: m...
> >> Hi, i am developing a battery (CR2032) powered device that must log a
> few
> >> sensors for a minimum of 3 months every minute but longer would be
> better.
> >> The duty cycle is very low. In order to save the data i will be using
> an
> >> SPI flash (16Mb). I was comparing at Atmel and SST (Microchip) and SST
> >> seems to have the lowest current consumption device (max 15uA at
> standby)
> >> but it is still a bit high compared to the microcontroller (MSP430 for
> >> instance) and other sensors. Acceptable but high. Does any one knows
> any
> >> other SPI flash with lower idle current and reasonble availability?
> >>
> >> Second.. does any one knows if there is any problem on powering the
> flash
> >> directly from the battery? Just asking becouse if there is a problem i
> >> will
> >> have to use a boost converter (more costly and less power efficient).
> >>
> >> Thank you!
> >>
> >> ---------------------------------------
> >> Posted through http://www.EmbeddedRelated.com
> >
> >
>
> I liked the power down idea, Very simple adn reduce to 1uA current due to
> the Mosfet. FRAM devices got very low memory or bulky packages so not the
> best solution for now. Any comment on powering a 2.7V flash from 3.0V coin
> battery? Thank you!
>
> ---------------------------------------

I think you would do better to find a SPI Flash Chip that is specified
in the data sheet to operate over a range of voltages that includes the
range of voltages you are likely to see from your battery. Do note that
some coin cells, when new, will show a higher voltage than the nominal
3.0 volts. I have seen some as high as almost 3.3V.

The Micron M25P15 part is specified to work correctly with a supply
voltage range of 2.7 -> 3.6 volts. This should work well with a coin
cell lithium battery as long as you make sure that your circuit shuts
down operation when the battery voltage nears 2.7V at dischard of the
batteryy.

http://www.micron.com/parts/nor-flash/serial-nor-flash/
~/media/Documents/Products/Data%20Sheet/NOR%20Flash/5976M25P16.ashx

--

Michael Karas
Carousel Design Solutions
http://www.carousel-design.com

"Arlet Ottens" <usenet+> wrote in message
news:4fb00052$0$6922$ ...
> On 05/13/2012 08:38 PM, Sink0 wrote:
>> Hi, i am developing a battery (CR2032) powered device that must log a few
>> sensors for a minimum of 3 months every minute but longer would be
>> better.
>> The duty cycle is very low. In order to save the data i will be using an
>> SPI flash (16Mb). I was comparing at Atmel and SST (Microchip) and SST
>> seems to have the lowest current consumption device (max 15uA at standby)
>> but it is still a bit high compared to the microcontroller (MSP430 for
>> instance) and other sensors. Acceptable but high. Does any one knows any
>> other SPI flash with lower idle current and reasonble availability?
>>
>> Second.. does any one knows if there is any problem on powering the flash
>> directly from the battery? Just asking becouse if there is a problem i
>> will
>> have to use a boost converter (more costly and less power efficient).
>
> How about turning off the power to the flash when you're not using it ?
>
>

Yep - power from a spare uC pin. It'a worked for me.

On May 13, 11:41*am, Arlet Ottens <usene...@c-scape.nl> wrote:
> On 05/13/2012 08:38 PM, Sink0 wrote:
>
> > Hi, i am developing a battery (CR2032) powered device that must log a few
> > sensors for a minimum of 3 months every minute but longer would be better.
> > The duty cycle is very low. In order to save the data i will be using an
> > SPI flash (16Mb). I was comparing at Atmel and SST (Microchip) and SST
> > seems to have the lowest current consumption device (max 15uA at standby)
> > but it is still a bit high compared to the microcontroller (MSP430 for
> > instance) and other sensors. Acceptable but high. Does any one knows any
> > other SPI flash with lower idle current and reasonble availability?
>
> > Second.. does any one knows if there is any problem on powering the flash
> > directly from the battery? Just asking becouse if there is a problem i will
> > have to use a boost converter (more costly and less power efficient).
>
> How about turning off the power to the flash when you're not using it ?

And buffer it to internal FLASH and/or EEPROM first.

On 2012-05-13 20:38, Sink0 wrote:
> Hi, i am developing a battery (CR2032) powered device that must log a few
> sensors for a minimum of 3 months every minute but longer would be better.
> The duty cycle is very low. In order to save the data i will be using an
> SPI flash (16Mb). I was comparing at Atmel and SST (Microchip) and SST
> seems to have the lowest current consumption device (max 15uA at standby)
> but it is still a bit high compared to the microcontroller (MSP430 for
> instance) and other sensors. Acceptable but high. Does any one knows any
> other SPI flash with lower idle current and reasonble availability?
>
> Second.. does any one knows if there is any problem on powering the flash
> directly from the battery? Just asking becouse if there is a problem i will
> have to use a boost converter (more costly and less power efficient).
>

The idea of using the internal memory falls apart when you consider
24 x 60 x 90 = 129600. With 3 sensors * 16 bit you need 7-800 kB.
An internal controller is going to be expensive...

I don't think that there are SPI flashes available with wide voltage
ranges. If I were you, I would regulate the system to 1.8V, using an
1.8V SPI Flash.

If you power the SPI flash from an I/O Port, then you may run into
a problem with power on reset times, forcing the SPI flash to be turned
on for an extended time eating power.

You can overcome this by caching some data before you turn on the
SPI flash. With 3 sensors @ 16 bit, and caching for an hour,
you need 360 bytes of RAM which is probably OK.
Writing to internal EEPROM/FRAM, might also be OK-

Not sure if you can get FRAM parts with 1.8V.
There are 0.9V parts in the AVR series which can run
from std AA batteries, and contain a boost to 3.3V.

Best Regards
Ulf Samuelsson



> Thank you!
>
> ---------------------------------------
> Posted through http://www.EmbeddedRelated.com

Winbond W25Q16BV? Supply voltage operating range 2.7 to 3.6 volts,
typical power-down current 1 µA (achievable by using the SPI "power
down" command).

Chris

On Sun, 13 May 2012 20:41:22 +0200
Arlet Ottens <usenet+> wrote:

> On 05/13/2012 08:38 PM, Sink0 wrote:
> > Hi, i am developing a battery (CR2032) powered device that must log
> > a few sensors for a minimum of 3 months every minute but longer
> > would be better. The duty cycle is very low. In order to save the
> > data i will be using an SPI flash (16Mb). I was comparing at Atmel
> > and SST (Microchip) and SST seems to have the lowest current
> > consumption device (max 15uA at standby) but it is still a bit high
> > compared to the microcontroller (MSP430 for instance) and other
> > sensors. Acceptable but high. Does any one knows any other SPI
> > flash with lower idle current and reasonble availability?
> >
> > Second.. does any one knows if there is any problem on powering the
> > flash directly from the battery? Just asking becouse if there is a
> > problem i will have to use a boost converter (more costly and less
> > power efficient).
>
> How about turning off the power to the flash when you're not using
> it ?
>
>

On 5/13/2012 2:38 PM, Sink0 wrote:
>
> Second.. does any one knows if there is any problem on powering the flash
> directly from the battery? Just asking becouse if there is a problem i will
> have to use a boost converter (more costly and less power efficient).
>
Haven't tried this with flash, but a serial EEPROM had a separate
battery power pin the would lock the device if Vcc wasn't a diode
drop higher. As a previous poster noted, the 3.0 on the data sheet
is a MINIMUM voltage, and they don't give a max, which made my
devices useless until I switched power pin from 3.3 to 5 V.