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Is it possibly to use a Bluetooth receiver as an on/off switch in a circuit board?

Ideally, I would set the Bluetooth receiver into a low energy/sleep mode and use it simply as an on/off switch on a device. There is a small battery connected to the circuit board and an LED light at the other end, just to test if this will work.

Ideally it works like so:

Android/iPhone sends signal to Bluetooth receiver Bluetooth receiver accepts the signal, then the LED light turns on/off I know many people use bluetooth devices to maintain a constant connection with their phone and/or constantly feed information, however this isn't my intention.

I simply want to use it as an on/off switch that my phone can communicate with at all times.

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You are looking for Bluetooth 4.0 I think. Lower BT versions are not made for energy efficient systems. Notice you probably want to stay connected to the BT device because:

  • Polling/inquiring is were BT normally wastes more power.
  • You may want to have "real time" response (you don't want to wait until the BT devices are synchronized). Going from standby to connected status may take from more than half a second (known address) to several seconds (unknown address) which is definitively a non real time response.

There are also low power modes for the BT (park, hold and sniff), which you can use to quickly change to the active (connected) status for data transmission.

Sorry for the mixed up ideas in the response, it is better if you read a little bit about BT versions and architecture if you are interested. Otherwise my advise is, again, go for BT version 4.

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  • \$\begingroup\$ thanks for the answer, so bluetooth 4.0 is my best bet and using a low power mode like (park, hold, and/or sniff) are my ideal options? Are there any benchmarks for how long you can leave a bluetooth device "open" for under certain battery conditions? While I'm asking my questions about bluetooth specifically, I just want to be able to send a signal from my phone to a device wirelessly and believe that bluetooth would be the most ideal connection type ? \$\endgroup\$ – user3226576 Apr 27 '14 at 23:43
  • \$\begingroup\$ Yes, it seems that Bluetooth Low Energy is currently your best bet. Firstly, BLE is optimised for low data throughput, such as your application. Secondly, BLE is extremely low energy, theoretically lasting for year/s on coin cell batteries. However, practically this depends on your data throughput and your duty cycle. \$\endgroup\$ – Youssif Saeed Apr 28 '14 at 8:02
  • \$\begingroup\$ Note that if you're using an android phone that it needs Android version 4.3 and needs to have Bluetooth low energy hardware integrated. When you use an iPhone you'll need the iPhone 4s or newer. Both your MCU and Bluetooth module needs to run on 3.3V. Known android phones compatible for BLE are the Sony Xperia z and HTC ONE m6 (these are 2 devices I'm sure of that they support BLE) \$\endgroup\$ – Handoko May 27 '14 at 15:05

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