A Multi-Mode Transmitter Supporting BT/BLE and 802.11b/g/n/ax for IoT Applications

A multi-mode 2.4GHz transmitter is presented to support Bluetooth classic (BT), Bluetooth low energy (BLE) and 802.11b/g/n/ax. The proposal features two separately optimized signal paths with a single RF port. Through a multilevel buck converter, PA power supply is designed adaptive to operation modes ensuring high power efficiency. In WiFi mode, 21.5dBm mask compliant output power can be measured with 22%/20% PA/Tx efficiency. With 40MHz 1024-QAM (MCS11) signals, the transmitter achieves -35dB EVM at 16dBm output power without digital pre-distortion (DPD). At BT basic rate, the output power is 15.8dBm and PA/Tx efficiency can be up to 27%/25%, respectively. The output power reaches 13dBm with EDR3 signals. The transmitter can deliver 10.5dBm power in BLE mode with 28%/21% PA/Tx efficiency. Implemented in 22nm CMOS technology, the transmitter (including phase modulator PLL) occupies 0.7mm² silicon area.