Power STOP mode

[cgrenier]

Posted on March 26, 2008 at 11:23

Power STOP mode

[cgrenier]

Posted on May 17, 2011 at 12:27

Hello,

I tried to get working power stop mode, I reach always ~485uA when I execute PWR_EnterSTOPMode(PWR_Regulator_ON, PWR_STOPEntry_WFI)... The MCU is a Cortex STM32F101... I used an external trig to wake up the MCU and it works. It comes back in power save mode at 480 uA. So, I have to reach 20uA in this mode. I would like to have to help to see what could be the problem. I don't use any external crystal. I use the RC internal oscillator and an external 32KHz pour RTC. Do I have to disable the internal oscillator before to go in sleep mode? This oscillator is used to controlled the operating system (Free RTOS). Do I have to do something with JTAG? I/O, peripherals, clock, etc. I hope to get an answer as soon as possible. Best regards Christian

[16-32micros]

Posted on May 17, 2011 at 12:27

Hi Christian,

Yoy can refer to our AN2629 Application note entitled : ''STM32F101xx and STM32F103xx low-power modes''

http://www.st.com/stonline/products/literature/an/13922.pdf

and its associated Firmware to run STOP Mode

http://www.st.com/stonline/products/support/micro/files/an2629.zip

, Hope this helps you :) Cheers, STOne-32

[cgrenier]

Posted on May 17, 2011 at 12:27

I have already read this application note.

But I have still the HSI clock enabled during STOP mode. I read document and I think the HSI must be disabled when STOP mode is enabled. I don't understand why HSI is still enabled. It's true that I don't have HSE enabled. I output HSI clock through MCO pin. I see a 8 MHz signal during STOP mode. Do you have an example to put MCU in STOP mode properly? Regards Christian

[cgrenier]

Posted on May 17, 2011 at 12:27

Hello,

So, in stop mode... the current could come back at expected value if I put I/O in good state? So now I have 350 uA... I will do what you said in last post. I let you know! Christian

[cgrenier]

Posted on May 17, 2011 at 12:27

I wrote bad information.

When I execute STOP mode, HSI clock is stopped. I output it and I don't see any signal. The current is about 350uA in STOP mode. And in Stand by mode is dropped to 10 uA. I would like to know the next step to find out the problem. If the MCU goes to 10uA in standby, that means each I/O is set correctly. Regards Christian

[gdp123a]

Posted on May 17, 2011 at 12:27

Hi Christian,

you say in your last message: ''If the MCU goes to 10uA in standby, that means each I/O is set correctly.'' One or more of your IOs could still be causing the extra current drain. Standby mode sets all the IOs to high impedance and is fairly immune to what is connected to the IOs. My suggestion would be to still investigate which pins might be causing the extra current drain. Make sure all pins are set to output and set to 0. If you have no luck with that, try setting them to inputs with a pull-down (or pull-up) - it might help you isolate where the current is going, Greg.

[cgrenier]

Posted on May 17, 2011 at 12:27

I modified I/O config to input pull-up and pull-down. The current is presently to 83 uA. I'm not too far of expected sleep current.

Thanks