LPC812 Current Consumption

[theodorosveryki]

Hi,

I am trying to replicate the current/power measurements of the LPC812 board. I have downloaded the AN11561 application note and source code from NXP and I downloaded the code for low power modes on my board.

However, I am getting ~3.2mA current consumption when in active mode and ~1.1mA when in sleep mode which is far off from the expected values. According to AN11561 and the datasheet of my microcontroller I would expect to see ~1mA when in active mode and ~0.7mA when in sleep mode.

Any suggestions on the cause behind the difference between the measured and the theoretical value?

Thanks in advance,
Theo

[Carlos_Mendoza]

Hi Theodoros,

Have you de-soldered the trimming potentiometer? It needs to be de-soldered to achieve the correct current consumption.

Hope it helps!

Best Regards,
Carlos Mendoza
Technical Support Engineer

[theodorosveryki]

Hi Carlos,

Thanks a lot for your reply - I really appreciate it. 

Yes, the trimming potentiometer has been removed and external power supply has been tested as well, giving the same results. Any other potential sources of error?

Thanks,
Theo

[Carlos_Mendoza]

Hi Theodoros,

Apologies for the delay. Are you modifying the example code or you are using the project as provided in the application note?

Thanks in advance for your response!

Best Regards,
Carlos Mendoza
Technical Support Engineer

[theodorosveryki]

Hi carlosmendoza‌,

Thank you very much for your reply. 

I am using the project provided in the application note without any alterations whatsoever.

Thanks,
Theo

[Carlos_Mendoza]

Hi Theodoros,

I have checked and I get the same results, this is because the current measured corresponds to both the the LPC812 MCU and the LPC-Link circuit.

Best Regards,
Carlos Mendoza
Technical Support Engineer