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CC2652R: Maximal statistical sleep current consumption under different temperature conditions

Part Number: CC2652R

Hello,

We are currently designing a small battery powered wireless IoT device. We are still in early design stage and are investigating several microcontrollers part-numbers. And I would like to know if you have additional data for some parts.

Because our sleep/wake duty cycle will be high, in our first estimation sleep current was the most critical characteristic. Our first estimation was based on an MCU with around 2µA sleep current, but lower is of course better. We have found several MCU which could work including several from TI. However I would like to know if you can provide maximal (in addition to typical) data regarding the power consumption of your devices and at higher temperature since our device will live at a certain range of temperatures? Ideally, something similar to what STMicroelectronics provides in their datasheet, for instance for the STM32WB15 (www.st.com/.../stm32wb15cc.pdf). In section 6.3.7, they provide tables not only with typical consumption, but also with maximum (+-4 sigmas) and at 25°C, 55°C, 85°C, and 105°C (though in our case 105°C is outside of the working range). These characteristics show that there is a substantial difference between typical and maximal, especially in the low power sleep modes, which I assume would be similar for TI parts and we want to be able to account for the worst with a good confidence level. You do provide data of evolution over temperature as a graph, but this is for typical and not maximal.

I chose CC2652R for this support ticket as it seems to be one of the lowest current in sleep mode, but we are still open to other BLE components with good compromise on power consumption and price if you have any recommandations.

Best regards,

François L.

  • Hello Francois,

    The SimpleLink CC13X2 and CC26X2 devices will offer the lowest power consumption during BLE operation.  Current vs. Temperature graphs are provided in the CC2652R datasheet for standby, RX, and TX modes.  SWRA487 is also provided for further current consumption recommendations and measurement methods.  Can you please specify which needs are not met by these resources?

    Regards,
    Ryan

  • Hello Ryan,

    Thanks for the quick reply. I am aware of these current vs temperature graphs in the datasheets, but these are for typical characteristics (I agree that it gives an idea of how the processor evolves with temperature, but we would like more than this).

    As I explained, in our specific case, the sleep current will account for most of the consumption as we have an extremely low duty cycle (our device will wake up at most once every 10 minutes or even less, we also plan to set advertising pretty low). I noticed through the datasheet provided by STMicroelectronics (for which they do provide typical AND maximal characteristics) that the relative difference for typical and maximal in ultra low power sleep modes is really high, and I suspect this is the same for TI's chips. For instance for the STM32WB15, the current consumption in shutdown mode with RTC enabled at 3V at 25°C is 0.55µA typ and 2310 max. Granted this is for +-4 sigmas but this is a factor of 4 in consumption. There doesn't seem to be such information in the datasheets of TI's chips, which means it could be more or it could be less. We would like to have at least some quantifiable idea of this impact, especially since the device we are designing will be made in a large enough quantity for it to be significant, and we would like to characterise it well. We will make our own measurement when the design is done as well, but it would make the choice of ICs easier if we had such information before hand.

    Best regards,

    François

  • Hi François,

    I don't believe we have other data aside from what Ryan has already provided. Your best bet might be to perform your own measurements for the specific use-case that you're seeking on a LAUNCHXL-CC2652R1 using the methods described in  SWRA487.

    Thanks,

    Alexis