LPC15xx SET_POWER API - what does this really control?

[nsmith17044]

I'm trying to get an understanding of the 4 different set_power mode options in the LPC1518.  Per UM10736 (V1.1) page 584:

/* set_power mode options */
#define PWR_DEFAULT 0
#define PWR_CPU_PERFORMANCE 1
#define PWR_EFFICIENCY 2
#define PWR_LOW_CURRENT 3

Section 34.4.2.2 seems to elude to this effecting only the M3 core. The LPCOpen documenation nor the rom_pwr_15xx.h file in the LPCOpen library code is of any help.

I do see about a 1.5 to 2 mA reduction in consumption at 24MHz core speed between PWR_LOW_CURRENT and PWR_DEFAULT.  I would like to know what really is being effected.  Are any peripherals or bus behaviors effected?  Anyone have any experience with these settings?  Is there better documentation on this somewhere? 

[nsmith17044]

Update: I found out (the hard way) that use of PWR_EFFICIENCY mode / profile appears to impact the IAP Chip_IAP_CopyRamToFlash() function.  With PWR_DEFAULT, the operation of that function works.  With PWR_EFFICIENCY the operation appears to be successful based on the response code, however the flash is not updated.  This is at a system frequency of 24MHz.

From that behavior I surmise that the power profile setting appears to effect the flash block some how.

[Carlos_Mendoza]

Hi Nathan,

Please take a look to the following thread:

Power-saving 

Best Regards!
Carlos Mendoza
Technical Support Engineer