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I have this RF remote/receiver. Though the manual says battery life for the receiver is at least 12 months, I easily get 2 years of operation on a fresh set of batteries. The receiver 4 uses AAA batteries, so that should be 6V at 1200 mAh. Assuming there are external factors like self-discharging, the battery life is further decreased by 15%. I'm basing my calculations from this calculator.

Battery Life in years = Battery Capacity in mAh / Current in mAh / 24 / 365 * (1 -.85)

So based upon a 2 year life span (and assuming the .15 constant is correct) is it fair assume that the receiver is drawing on average around 58uA?

I realize I'm making some assumptions here, like the .15 constant. And I'm fairly sure the receiver is operating in sleep mode and waking up, but I want to make sure I understand this before addressing those assumptions.

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    \$\begingroup\$ Seems like a good estimate. If you need to know for sure, measure it. \$\endgroup\$
    – user57037
    Commented Dec 27, 2016 at 7:03
  • \$\begingroup\$ could be hard to measure if you don't have a data logger. \$\endgroup\$
    – Jasen Слава Україні
    Commented Dec 27, 2016 at 8:04
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    \$\begingroup\$ In the manual it says the receiver operates on AA batteries.Note that batteries have a voltage-mAh discharge curve,which means that as you consume the battery energy,their total voltage drops.The linked document says that the receiver must be supplied with at least 5.3V.Have you considered this? \$\endgroup\$
    – Daniel Tork
    Commented Dec 31, 2016 at 13:24
  • \$\begingroup\$ You have a mistake: "Current in mAh", unit of current is mA, not mAh \$\endgroup\$
    – Chupacabras
    Commented Feb 2, 2017 at 14:50
  • \$\begingroup\$ Self discharge is no external factor, it is internal of the battery. \$\endgroup\$
    – Uwe
    Commented Dec 4, 2022 at 8:18

2 Answers 2

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IMHO you are doing it wrong. your calculations are only correct if the RF remote is constantly working and sending signals. And I think the 12 months is estimated by the manufacturer for an average household usage of the product.

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    \$\begingroup\$ OP's calculation of 58 uA avg. is still correct when his personal use pattern of the remote control is the consideration, because a few bursts of high current consumption and long period of no current consumption is still equivalent to a very low constant current consumption on average. So the result can be described as entirely correct. Nevertheless, I agree that it's probably a bit misleading: If the remote is used more frequently by someone else, the calculated average current consumption should also increase. \$\endgroup\$
    – 比尔盖子
    Commented Nov 3, 2020 at 19:37
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The receiver seems to be a bad construction regarding battery life. Four AA cells are used but the minimum voltage is 5.3 V. So a cell may be discharged from 1.55 V to 1.325 V only. The remaining capacity from 1.325 V down to 0.8 or 0.9 V may not be used. Instead of 4 cells only the receiver should use 6 or even 7 cells together with a low drop high efficiency switching regulator. But for a rf receiver the switching regulator may be a problem. But 9 or even 10.5 V from fresh cells may be too much for the receiver. A linear regulator to 5.3 V would waste a lot of the battery capacity. To design a receiver to work with the full voltage swing from 10.5 down to 5.3 may be difficult and affect frequency stability. Using 6 or even 7 instead of only 4 batteries is very uncommon for those kind of electronics.

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