topic Running code from SRAM instead of on-chip Flash to save power? in LPC Microcontrollers

Running code from SRAM instead of on-chip Flash to save power?

lpcware — Wed, 15 Jun 2016 18:34:13 GMT

Content originally posted in LPCWare by Kaveh.Firouzi on Wed Jul 16 09:11:11 MST 2014
Hello,

Does running the code from SRAM instead of the on-chip flash on a processor such as LPC4357 make any significant difference on the power consumption level?

Regards

Re: Running code from SRAM instead of on-chip Flash to save power?

lpcware — Wed, 15 Jun 2016 18:34:14 GMT

Content originally posted in LPCWare by nerd herd on Wed Jul 16 11:00:00 MST 2014
Hi,

On a theoretical level, if the flash is not being used then it may be turned off to save power. The same can not be said for the SRAM as that is volatile memory. That said, I'm currently working on a project that involves measuring the current consumed by an LPC18xx experiment board and I can tell you that the flash seems to have higher current consumption compared to SRAM.

Re: Running code from SRAM instead of on-chip Flash to save power?

lpcware — Wed, 15 Jun 2016 18:34:15 GMT

Content originally posted in LPCWare by Kaveh.Firouzi on Fri Jul 18 10:48:59 MST 2014
Hi,

Thank you. So I went ahead and tested it on a LPC4357 processor, the reduction in current consumption was not significant

Re: Running code from SRAM instead of on-chip Flash to save power?

lpcware — Wed, 15 Jun 2016 18:34:15 GMT

Content originally posted in LPCWare by nerd herd on Fri Jul 18 12:32:00 MST 2014
Hi,

After collecting some numerical data through testing, the reduction of current seemed to be about a few mA, but I was unsure if on-chip flash was fully turned off. Are you trying to lower power consumption for active mode in your application? If so, we can try other things to save power. :)

Re: Running code from SRAM instead of on-chip Flash to save power?

lpcware — Wed, 15 Jun 2016 18:34:16 GMT

Content originally posted in LPCWare by Kaveh.Firouzi on Fri Jul 18 12:55:30 MST 2014
Hi,

Yes, I am trying to reduce power consumption for active mode, where should I start?!

Re: Running code from SRAM instead of on-chip Flash to save power?

lpcware — Wed, 15 Jun 2016 18:34:17 GMT

Content originally posted in LPCWare by nerd herd on Fri Jul 18 14:02:38 MST 2014
Hi,

So what I would start with is disabling any peripherals that you are not using in your application through the clock generation unit (CGU). So for example, if your application only requires UART0 and an SPI (SSP) connection, try to disable any of the other peripheral clocks to reduce the current consumption. Chapter 12 in the user's manual has information on the CGU and what the relevant registers are:

http://www.nxp.com/documents/user_manual/UM10503.pdf

Let me know if you have any questions about this!