Low Power Ticker

https://os.mbed.com/docs/v5.6/reference/lowpowerticker.html

Has anyone successfully implemented the LowPowerTicker? I tried this example above but it has build errors (230). I have used Ticker without issue but when using LowPowerTicker I get errors when trying it outside the above example as well. I get … Identifier “LowPowerTicker” is undefined… error. I have #include “LowpowerTicker.h”. So I not sure why it wont recognize it. And I tried updating as well.

I am using Nordic nrf51xxx series.

thanks