Author Topic: RFM69W and RFM69HW current consumption  (Read 2956 times)

selcouth

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RFM69W and RFM69HW current consumption
« on: March 16, 2015, 11:32:45 AM »
I've read that the RFM69W has ~45mA current consumption at 13dB and the RFM69HW has ~130mA current consumption at 20dB. If I lower the transmit power on the RFM69HW down to RFM69W levels (13 dB and lower) is the current consumption roughly the same between the models or is the RFM69HW always going to consume more?

Felix

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Re: RFM69W and RFM69HW current consumption
« Reply #1 on: March 16, 2015, 01:21:08 PM »
That measure of consumption is directly related to the transmit power. So lowering the TX power will decrease the consumption. You should expect the same consumption all other things equal.

selcouth

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Re: RFM69W and RFM69HW current consumption
« Reply #2 on: March 16, 2015, 01:48:11 PM »
Great, that was my assumption. I think I'll stick with the HW models for my project then as I can crank the power up if needed or keep them low if they're working just fine.

Thanks again!

TomWS

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Re: RFM69W and RFM69HW current consumption
« Reply #3 on: March 16, 2015, 03:05:14 PM »
<snip> I think I'll stick with the HW models for my project then as I can crank the power up if needed or keep them low if they're working just fine.
<snip>
Good decision. 

You might want to take a look at the library referenced in this post: https://lowpowerlab.com/forum/index.php/topic,966.msg6195.html#msg6195.  It provides automatic transmit power control so that the radio automatically adjusts the transmit level to meet your receive signal quality goal.  You can freely start with the RFM69HW set to max power and it will automatically dial back to a lower setting until the far end receives a sufficient, but not wasteful, signal level.

Tom