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I am using JenNet-IP stack and JN5148-J01 MCU for smart home application. As per JenNet-IP stack my MCU will not be in sleep mode because it is working as router in WPAN.

But I have to reduce current consumption using sleep mode. My results are as follows:

  • Without Sleep Current - 18 mA.
  • In sleep mode - 1.05 mA.

Problem is, in sleep mode my radio will be turned OFF. So, I will not get any interrupt when any RF packet received.

So how can I reduce current consumption with radio ON?

if anyone has used wake up timers , then please provide me sample code of wake timer for JN5148-J01.

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You cannot.

Unfortunately, to have the radio capable of receiving signals, it has to be powered up. The datasheet states a typical consumption of 17.5 mA for the radio in receive mode, even with the CPU sleeping.

You can do some tricks with turning the radio off for short periods of time, though.

For example, if you run the radio until you see the other node you want to talk to, you could have the two nodes agree to queue transmissions between the nodes for a period of time, and then both reactivate their radio after a set period of time.

Basically, if both nodes agree to sleep for say 10 ms, and then activate their radios for 1 ms, you can reduce power consumption by 90%, at the cost of a equivalent loss of data bandwith. Since this is smart-home stuff, I'd assume it's much lower bandwith then the theoretical radio throughput, it will likely not be an issue.

You would want the nodes to resynchronize at every interval, to minimize clock drift.

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  • \$\begingroup\$ It seems like , by using wake timers i will be able to reduce power consumption. \$\endgroup\$ – Dhaval Chauhan May 3 '14 at 8:29
  • \$\begingroup\$ I have NXP jennic EK-040 development kit.I am using carrier board-DR1174 , and MCU - JN5148-J01.In deep sleep mode i am getting 1.05 mA , which is not desirable. So how can i get deep sleep current less than 50 uA? \$\endgroup\$ – Dhaval Chauhan May 3 '14 at 8:33
  • \$\begingroup\$ @DhavalChauhan - Assuming you have the DR1174 in low-power mode (it describes how to set it in that mode in the docs), start turning off all the MCU's internal peripherals. Look for things like connected voltage regulators, etc... that are still powered, and don't need to be. \$\endgroup\$ – Connor Wolf May 3 '14 at 9:24

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