The ADMV4928 from Analog Devices is a 5G SOI (Silicon on Insulator) Beamformer IC that operates from 37 to 43.5 GHz. This dual polarized RFIC has 16 configurable transmit and receive channels with support for eight horizontal and eight vertical polarized antennas via independent RFV and RFH input/outputs. In transmit mode, both the RFV input and RFH input signals feed into separate amplifiers. Each path after amplification splits into eight independent channels via 1:8 power splitters. In receive mode, input signals pass through either the vertical or horizontal receive channels and combine via two independent 8:1 combiners to the common RFV pin or RFH pin.
The transmit channels contain individual transmit power detectors to detect either modulated or continuous wave signals to calibrate for each channel gain as well as a channel to channel gain mismatch. Each receive channel contains an RF power overload circuit (receive channel overload detection circuit) to prevent potential damage to the device.
The ADMV4928 has an integrated high resolution 6-bit vector modulator (VM) for phase control and two high resolution 6-bit and 5-bit digital variable gain amplifiers (DVGAs) for amplitude control. The VM provides a full 360° phase adjustment range in either transmit or receive mode to provide 6 bits of resolution for 5.625° phase steps. In Tx mode, the total DVGA dynamic range is 34.5 dB, which provides 6 bits of resolution in 0.5 dB steps and 5 bits of resolution in 1 dB steps. In Rx mode, the total dynamic range is 28 dB, which provides 5 bits of resolution with 0.5 dB steps and 5 bits of resolution with 1 dB steps.
The ADMV4928 has a non-volatile memory (NVM) for phase and gain calibration, on-chip memory that can store up to 2048 shared transmit/receive beam positions, and an on-chip LDO voltage regulator for 1 V. It requires a dual DC supply of 1.8 and 1.2 V. This beamformer is available in a 239-ball CSP BGA package that measures 10 x 7 mm and is ideal for mmWave 5G and broadband communication applications.
