nRF51422-QFAA-R v2 NRF51422-QFAA-R_REV3 NRF51422-QFAA-R7 nRF51422-QFAA-Rv2 NRF51422-QFAA-T NRF51422-QFAA-T REV2 NRF51422-QFAB-R NRF51422-QFAB-R7 NRF51422-QFAB-T NRF51422-QFAC