stm32l072rz higher stop mode current then stm32l072rb

[andrea-al2tech]

Hello,

we have a validated project based on the stm32l072rb (FLASH 128KB) microcontroller and in stop mode the entire system consumes 3.5uA.

We have updated to the stm32l072rz (FLASH 192KB) and the stop mode current raised to 23uA. 

In standby mode both boards consume 3uA.

Are there different actions we have to take to enter stop mode between the two uC which differ only in flash size?

Thanks for your help,

Andrea

[Andrew Neil]

---

@andrea-al2tech wrote:

Are there different actions we have to take to enter stop mode between the two uC which differ only in flash size?

---

No.

Are you sure the code is identical?

Are the boards identical?

Remember, at this level the leakage from other components - eg, capacitors - can become significant ...

[andrea-al2tech]

Boards are Identical and we have flashed the same code!

[Andrew Neil]

There's still scope for (some/most of) the extra leakage to be from things outside the STM32 ...

[andrea-al2tech]

One thing I forgot to mention is that in STANDBY MODE both boards consumes around 3uA. That is why I think it is is something inside the uC!!!

[waclawek.jan]

Which revision is the 'L072RZ? There's a FLASH-related erratum for rev.A, and while it does not mention increased power supply, you can try the workaround mentioned there, i.e. setting FLASH_ACR.RUN_PD before entering Stop (it probable needs to be done while running code from RAM, together with going to Stop; and it needs an unlock described in the RM).

JW