Lpc2000

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