I’m worried about the power consumption of my DWM1001 devices.
A tag with update rate of 100ms needs around 14 mA
A tag with update rate of 10 seconds needs 27 mA
I expected that at a lower refresh rate consumption would be lower
What is this behavior due to?
Suboptimal software and/or protocols.
The DW1000 chip is capable of operating at those rates at very low average power. A short beacon every 10 seconds with SLEEP or DEEPSLEEP between packets should average under 10 uA from a 3.3 volt supply. Yes, that’s microamps. What you are observing is very far from what the hardware is capable of and it is particularly peculiar that power usage goes up at the slower rate.
Low power operation is a complex interplay of hardware, firmware, and protocol design. The key is to design the protocol so that transmit or receive only occurs during precise and short intervals so the DW1000 can be sleeping almost all the time. It is possible to design tags that last many years this way. Tags can still have good update rates when combined with other techniques, such as wake on shake that uses accelerometers to increase tag rates during movement, and then slow them down during static conditions.
Mike Ciholas, President, Ciholas, Inc
3700 Bell Road, Newburgh, IN 47630 USA
+1 812 962 9408
I’ve faced a similar issue. We work with DWM1001 so I don’t really know if we have control over the sleep or deep sleep state. We measured the power consumption in active mode, so I assume neither the tag nor the anchor will be on sleep state.
We also saw that the power consumption went high when lowing the update rate.
Assuming you are using PANS on the MDEK1001: have you tried turning of the LEDs and Bluetooth? Also note that there is a Low Power mode that can be activated in order to keep the power consumption down, see the System Overview.
My explanation for seeing a higher consumption when using a lower update rate would be the LEDs: the lower update rate causes the LEDs to be on for a higher proportion of the time.
Hi @seppe we are using PANS Release 2 on the DWM1001. We have BLE off and LEDs on. We can expec some conpsumtion encrease because of this, that we assume it. What we would like to understand is why, given the same Leds/BLE conditions, when we are variating the update rate to slower ones we don’t see a decrease in consumption.
Hope this explanation is more helpul,
As I explained before, the behavior of the LEDs could be different depending on the update rate. Please have a look at disabling the LEDs and ensuring the tag is configured in low power mode, which should ensure the DW1000 chip is put in low power mode like @mciholas describes.
Not doing this will prevent the system from going to lower power sleep modes and this explains the higher current consumption you are seeing.
Please note the DWM1001 refers to the the module itself. The module mounted on the development board is referenced as DWM1001-DEV, which is what I now assume you are using.
Hello again @seppe yes, we are using DWM1001-DEV. I’ve disabled the leds using the android app, there’s still one that is on while the device is on, that is how I developed the consumption tests. All the test were carried on the same device, with the same led /ble configuration. The only thing we changed was the update rate so that’s why I can’t understand the described behaviour
Hi @seppe any more omfp about why we observe such a high power consumption?
Please understand that we are using the evaluation kit out-of-the-box using PANS R2, the android app and the web manager tool to visualize our system. We don’t have control over the code that runs on the device.