Author Topic: inAir9b Sleep Current  (Read 1691 times)

kiwironnie

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inAir9b Sleep Current
« on: July 29, 2016, 04:34:10 PM »
So far I can find no way to reduce the current draw of the inAir9b below about 300uA, in sleep mode with Vswitch off.
Indeed the module consumes pretty much that current by hooking up just its power pins.
When in sleep mode I've checked the sx1276 RegOpMode register to ensure that the radio is actually in sleep mode and also confirmed an expected increase in current by shifting to standby mode, then a corresponding decrease by shifting back into sleep.
The apparently high current doesn't seem right as the sx1276 itself is supposed to draw less than 1uA in sleep mode.
Tested this with a different inAir9b module, same thing.
Can anybody suggest what might be the issue?
Many thanks, Ron

PS - So, with no response to the above, I can only assume that the minimum current draw of the inAir9b is around 300uA.
« Last Edit: August 07, 2016, 12:07:18 PM by kiwironnie »

modtro2

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Re: inAir9b Sleep Current
« Reply #1 on: August 21, 2016, 06:06:31 PM »
Hi, the inAir4, inAir9 and inAir9B boards consist of just the SX1276 or SX1278 chip and the voltage switch (vswitch). Only these two items will consume power. And, when the voltage switch is disabled, it is only the SX1276/8 chip that consumes power. Our inAir4, inAir9 and inAir9B modules consume exactly the currents given in the SX1276/8 datasheet. You must be doing something wrong if you are getting 300uA. Do you have all inputs of the SX1276/8 chip connected to 0 or 3.3V? Leaving an input floating can cause it to oscillate, consuming a lot of power. Also note the the SX1276/8 chip is very complex, and you have to ensure your software is configuring it for the correct low power mode.