A 0.85mm2 BLE Transceiver Using an On-Chip Harmonic-Suppressed RFIO Circuitry With T/R Switch

This article presents a small-area Bluetooth Low-Energy (BLE) transceiver (TRX) for short-range Internet-of-Things (IoT) applications in 65-nm CMOS. An integrated Radio-Frequency Input-Output (RFIO) circuitry embedded with transmitter/receiver (TX/RX) switch function and on-chip impedance matching is proposed. A hybrid-loop TRX structure based on a wide-bandwidth fractional-N digital phase-locked loop (DPLL) is implemented to achieve the maximum power reduction. A −94dBm receiver sensitivity is achieved with 2.3mW receiver power consumption, while a RF receiving bypass route integration enhances the input power tolerance. The BLE transceiver delivers −6dBm output power while consuming 2.6mW and delivers 0dBm output power while achieving 18.5% maximum TX efficiency. Thanks to the RFIO with harmonic suppression, −56dBc of 2 $^{\mathrm{ nd}}$ -order harmonic distortion (HD2) and −48dBc of 3 $^{\mathrm{ rd}}$ -order harmonic distortion (HD3) suppression are achieved with 0.85mm2 on-chip area. This transceiver satisfied the BLE radio specification without the need for external filters and with low-power consumption, which enables minimum size and long life-time modules.