About DW3000 power supply via 3.7V lithium battery

Wireless Connectivity Ultra-Wideband
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Hi everyone，

I am designing a PCB for a portable DW3000 product.

But the lithium battery voltage is not fixed（4.2V-2.8V，Nominal voltage：3.7V）.

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I know I need to adjust the voltage of VDD3 to 1.6V via DC-DC.

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I have no idea what level should I adjust the voltage of VDD1&2.

2.5V 、2.8V 、3.0V or 3.3V？Which voltage level has the best efficiency and lower power consumption？

Can you give me some power supply solutions?

THX :heart:
KK

1 Like
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  1. You cannot connect dw3000 directly to li-po
  2. Depending on your product, if cost is tooimportant, then use 1 dc-dc 2.8/3.0V, the same you would use for your MCU.
    If cost/simplicity not too important, use 2 or 3 DC-DC. 1.8V, (2,6V) and 3.0V

Please note, the phase noise on the power rail is quite important, so if you not sure, or have small quantities, then use DWM3000.
I also would recommend to not use too sophisticated dc-dc with PFM/PWM automatic switch, as usage these parts could be really tricky - you can experience all the fun and scream “not working” just by selecting wrong HW components.

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Hi @alliv

Thank you very much for your advice.

Because I’ve never worked on a DW1000 product.

I want to make a product similar to Apple AIRTAG.
【Priority:
Lv1：Low power consumption (TWR ~10 times a day, can work for several months)
Lv2：PCB Size
Cost is not important】

There are too few reference circuits for this type of product.

I don’t know the power supply circuit for UWB watches or electronics tags.

How many 100uF tantalum capacitors are needed for UWB peak current，if use CR2032 as power supply?

The DW3000 has a lot of LDO inside.Can counteract the noise problems caused by DC-DC？

Hope for more advice.

Thx
KK

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Typical AirTag does not range 10 times a day.
It typically does not do UWB ranging until called.

So your target is to have the lowest possible BLE advertisement current consumption for as long as you can, then, when the time comes - activate UWB and do TWR.

If your target is CR2032, it has a very low peak current consumption allowance (20mA). It is better to use a Li-Pol battery.
Both, but CR2032 more may require several caps to coop with peak current consumption connected to DW3000. I would recommend adding a power switch that is driven by MCU and disconnecting the whole uwb circuit from the battery. - that would give you the longest possible battery life, as that would remove unwanted leakages from all the circuits.

Qorvo has reference SW which supports Apple Nearby Interaction with 3rd party accessories Beta program - but that SW is not low-powered. Search Qorvo website.

I think they should work on a low-power version and you need to request close to your location sales for more information.