Cheapest nrf51822 peripheral available ?

[Mohib]

Hi, CAn anyone plz help me getting the cheapest possible nrf51822 small module that i can use in my project as peripheral ?

Or any other module that can work as slave with nrf51822 ek that is central ?

Any help will be appreciable .

[Mahesh Venkitachalam]

You can find several nrf51822 modules for under 6 USD on Aliexpress. For example:

www.aliexpress.com/.../32281199327.html

But if you are buying in volume (1000 pcs) you can find better modules for around 3.5 USD.

The central/peripheral roles can be switched by just changing the softdevice, as far as I understand.

Update #1:

Based on RK's comment below, here is a link to Nordic docs on chip versions:

www.nordicsemi.com/.../39119

[RK]

They're not - that's one of the issues with 3rd party module manufacturers - you have no idea how many they made and how many they sold and whether or not they are sitting with a pile of rev 1's to ship, so regrettably you have to ask them and hope they are honest.

Fairly recently one poor chap on the list here did ask seeed micro what they were using, and was assured it was rev 2, however when he actually bought them (from a distributor in Germany) they turned out to be rev 1, and he had a bunnyload of problems.

I'd love there to be a better way to do this - perhaps sticking to Nordic's 3rd party list might be a good idea, however most of them also don't say, so you still have to ask.