Lpc2000

Hi,

first of all, I would like to thank Rick (redspy) for being persistent
enough to trigger more investigations on power usage on the LPC2000
devices. 

These measurements have been conducted with Vdd=1.8V on LPC2129
devices but are fairly representative for all the 64-pin devices.

A device coming from Reset has all peripherals enabled and running at
max speed 60 MHz with MAM and PLL enabled uses between 35 mA and 40 mA
when executing the Blinky program.

Going from here there are options to decrease or increase the power.
At reset all peripherals are enabled as mentioned above BUT there is a
divider for the peripheral clock implemented that slows down the clock
to the peripherals. It is called VPB divider and serves two purposes:

1. Enabling Philips to use slow peripherals if needed
2. To reduce power consumption if peripherals do not need to run full
speed. 

The divider is set to /4 at reset and reduces the power consumption of
the total peripheral block. If all peripherals remain active AND the
divider is set to /1, the power consumption increases by approx. 15mA
into a range between 50-55 mA. 
The other option to change power related to peripherals is by using
the PCONP register. Setting the PCONP register to all "0" reduces
power but leaves you stranded without peripherals. Please check the
User Manual for details which bits enable which peripheral. As a rule
for power saving, it is good practice to set the whole register to "0"
and enable the peripherals you want to use.
Depending on the setting of the VPB divider power usage of the
peripheral block with all peripherals active and max speed is between
15-20 mA but with VPB divider set to /4, it is between 3-5 mA.

Summary:
You can run the CPU at full speed, have all peripherals active and
still use around 40mA when the clock to the peripherals is divided by
a factor of 4.
The upper end of the power consumption we saw in the range of 55mA
with everything running at max. frequency and all peripherals active,
no divider. 

Hope this answers many questions that have come up in the past. 

How does this relate to the LPC2104/5/6.
All numbers are a lower by a few milliamps but in general the behavior
is very similar. 

Best regards, Robert

Hello Robert,

> A device coming from Reset has all peripherals enabled and running 
at
> max speed 60 MHz with MAM and PLL enabled uses between 35 mA and 40 
mA
> when executing the Blinky program.

how does this 40mA divide over the 3.3V and 1.8V rails?

bye,
G

I thought that I had replied to this earlier, but I don't see it in
the list.  


--- In lpc2000@yahoogroups.com, "philips_apps" <philips_apps@y...> wrote:
> Hi,
> 
> first of all, I would like to thank Rick (redspy) for being persistent
> enough to trigger more investigations on power usage on the LPC2000
> devices. 

It is my nature to be persistent, sometimes it gets results, other
times it ticks people off.  I am glad that you responded with
results... :)


> These measurements have been conducted with Vdd=1.8V on LPC2129
> devices but are fairly representative for all the 64-pin devices.

Will these numbers find their way into the data sheets?  Other
manufacturers publish the data so that it is easier to estimate power
consumption for various modes of operation.  If it is in the data
sheets, we don't have to bug you in the message groups.   

I am more interested in the 22xx, 144 pin parts since I would like to
use the external data bus.  So far I have not been able to get much
dependable info on the schedule.  My local sales contact is not
forthcoming with much info.  Is there a planned delivery date other
than just second half of the year?  Would it be at all practical for
me to plan production in July or August?  

The other issue I have with these parts is the size.  A 144 QFP is
just too large for this app.  Are any smaller packages planned for the
higher pin count parts?  BGA perhaps?

Hello G,

the 1.8V supplies all logic on the device, no matter whether it is the
CPU or peripherals. This is the power consumption of the chip. On the
other hand, the 3.3V supplies I/O drivers only (and the analog part of
the ADC). This supply is virtually "0" as long as you don't drive
external load. Driving externally 2 mA adds 2 mA to the 3.3V current.
In other words, the 3.3V power consumption is only limited by your
application and the max power dissapation of the whole
microcontroller, it is not something the the microcontroller per say
uses. It is the external components that use this power. Not included
in the power measurement or better, our tests would only find the
current necessary to drive the logic gates that in turns drive some LEDs. 

Hope I could make it clear why 3.3V is not really part of the
microcontroller power consumption.

Regards, Robert

--- In lpc2000@yahoogroups.com, "golssa" <golssa@y...> wrote:

> Hello Robert,
> 
> > A device coming from Reset has all peripherals enabled and running 
> at
> > max speed 60 MHz with MAM and PLL enabled uses between 35 mA and 40 
> mA
> > when executing the Blinky program.
> 
> how does this 40mA divide over the 3.3V and 1.8V rails?
> 
> bye,
> G

Hi Rick,


> > These measurements have been conducted with Vdd=1.8V on LPC2129
> > devices but are fairly representative for all the 64-pin devices.

Will these numbers find their way into the data sheets?  Other
manufacturers publish the data so that it is easier to estimate power
consumption for various modes of operation.  If it is in the data
sheets, we don't have to bug you in the message groups.   

<R> It is a little difficult to get typical numbers into data sheet
because they are not tested for each device. 

I am more interested in the 22xx, 144 pin parts since I would like to
use the external data bus.  
<R> Power numbers are pretty much identical (less than 1 mA
difference) because the only additional "logic" are port pins and
control pins for the bus. Otherwise same peripherals, same CPU.
  
So far I have not been able to get much dependable info on the
schedule.  My local sales contact is not forthcoming with much info. 
Is there a planned delivery date other than just second half of the
year?  Would it be at all practical for me to plan production in July
or August?  
<R> Well, can't really comment too much on this one. I do know that we
have multiple lots in production flow but I don't know how many orders
are already in the system. By July / August we will have delivered >>
100k pieces, nevertheless, I can't tell you where they go to. There is
one promise though, they will be spread widely.

The other issue I have with these parts is the size.  A 144 QFP is
just too large for this app.  Are any smaller packages planned for the
higher pin count parts?  BGA perhaps?

<R> Plans exist but it is going to be midterm, not within the next 4-6
months.

Regards, Robert

--- In lpc2000@yahoogroups.com, "philips_apps" <philips_apps@y...> wrote:
> Hi Rick,
> 
> 
> > > These measurements have been conducted with Vdd=1.8V on LPC2129
> > > devices but are fairly representative for all the 64-pin devices.
> 
> Will these numbers find their way into the data sheets?  Other
> manufacturers publish the data so that it is easier to estimate power
> consumption for various modes of operation.  If it is in the data
> sheets, we don't have to bug you in the message groups.   
> 
> <R> It is a little difficult to get typical numbers into data sheet
> because they are not tested for each device. 

Trying to be persistent without being annoying - if you don't put them
in the data sheet, how will users get the info?  I see all sorts of
numbers in data sheets that are neither tested or guaranteed.  

"[1] Typical ratings are not guaranteed. The values listed are at room
temperature (+25 °C), nominal supply voltages.

[2] Pin capacitance is characterized but not tested."

I think if you omit power consumption info from your data sheets, you
will be disappointing a lot of users who need this info to begin
designs.  Even if user's designs are not running from batteries, they
need to be able to calculate requirements for the power supplies. 
 

It does not matter much to me since I don't think I can use the
Philips parts.  But I am sure I am not the only user who would need
the power info in the data sheet.  :)

It would also be of interest to have some power measurements in other 
configurations:
- Idle mode with peripherels enabled and disabled
- 10 MHz without PLL


--- In lpc2000@yahoogroups.com, "philips_apps" <philips_apps@y...> 
wrote:
> Hi,
> 
> first of all, I would like to thank Rick (redspy) for being 
persistent
> enough to trigger more investigations on power usage on the LPC2000
> devices. 
> 
> These measurements have been conducted with Vdd=1.8V on LPC2129
> devices but are fairly representative for all the 64-pin devices.
> 
> A device coming from Reset has all peripherals enabled and running 
at
> max speed 60 MHz with MAM and PLL enabled uses between 35 mA and 40 
mA
> when executing the Blinky program.
> 
> Going from here there are options to decrease or increase the power.
> At reset all peripherals are enabled as mentioned above BUT there is 
a
> divider for the peripheral clock implemented that slows down the 
clock
> to the peripherals. It is called VPB divider and serves two 
purposes:
> 
> 1. Enabling Philips to use slow peripherals if needed
> 2. To reduce power consumption if peripherals do not need to run 
full
> speed. 
> 
> The divider is set to /4 at reset and reduces the power consumption 
of
> the total peripheral block. If all peripherals remain active AND the
> divider is set to /1, the power consumption increases by approx. 
15mA
> into a range between 50-55 mA. 
> The other option to change power related to peripherals is by using
> the PCONP register. Setting the PCONP register to all "0" reduces
> power but leaves you stranded without peripherals. Please check the
> User Manual for details which bits enable which peripheral. As a 
rule
> for power saving, it is good practice to set the whole register to 
"0"
> and enable the peripherals you want to use.
> Depending on the setting of the VPB divider power usage of the
> peripheral block with all peripherals active and max speed is 
between
> 15-20 mA but with VPB divider set to /4, it is between 3-5 mA.
> 
> Summary:
> You can run the CPU at full speed, have all peripherals active and
> still use around 40mA when the clock to the peripherals is divided 
by
> a factor of 4.
> The upper end of the power consumption we saw in the range of 55mA
> with everything running at max. frequency and all peripherals 
active,
> no divider. 
> 
> Hope this answers many questions that have come up in the past. 
> 
> How does this relate to the LPC2104/5/6.
> All numbers are a lower by a few milliamps but in general the 
behavior

> is very similar. 
> 
> Best regards, Robert