Hello, I work on a product with LSM303AGR and STM300 module. The problem is : when the LSM303AGR goes to sleep, it works. After, I try to get EnOcean module to sleep, then the LSM303AGR consume 500µA. Any idea?

[Jérémy Da Silva]

The SPI works well. I can asleep the sensor but when I try to asleep the EnOcean module, I see that the sensor consume near 500µA. I have put two pull down on SDI/SDO and SCL and two pull up on the CS_ACC and CS_MAG.

[Miroslav BATEK]

Considering the high current consumption is only when the EnOcean module is in sleep mode and the GPIO are probably in high-Z, the problem could be cause by undefined level on the CS pins. The pull-up 10M are very week. You can try to decrease the value. But it is just my idea.

Btw. are you sure the high current is drawn by LSM303AGR?

[Jérémy Da Silva]

Hi,

I have decreased the value of the pull-up resistors but nothing happened.

I'm sure that high current is drawn by LSM303AGR because I have put one ammeter on the VCC of the EnOcean module and another of VCC of LSM303

[Miroslav BATEK]

I don't know which value of the pull-up you used, but please try following:

Put two 10k pull down resistors on SDI/SDO and SCL and two 10k pull up resistors on the CS_ACC and CS_MAG. Input pins must always be driven high/low (no floating).

[Jérémy Da Silva]

Hi,

I have the same behavior...

[Daniel.J]

Hi,

@Jérémy Da Silva​ , did you solve your problem?

I'm having what I guess is a similar problem.

When I put the accelerometer in power-down mode it starts consuming way too much power(~650 uA).

If I put it in low power mode it goes down to ~10uA(the whole system).

I'm figuring it has something to do with pin states as you've discussed.

Is it okay to have CS_X pins tied to VDD?

I've tried that in combination to pulling I2C pins high/low without success.

EDIT: I just solved my problem, the solution was to put the INT_MAG signal to a pullup.

[Miroslav BATEK]

OK, this is what I recommended in the thread.