A Highly-Efficient 4.3 GBaud Push-Pull LDMOS Based Pre-Driver with 6V Signal-Swing for GaN HEMTs in 22 nm FDSOI

The paper presents a highly power efficient push-pull LDMOS-based pre-driver, implemented in a 22 nm FDSOI CMOS process, generating an output voltage swing of 6 V for GaN-based switching power amplifier with an estimated capacitive load impedance of 0.35 pF. This is achieved by utilizing monolithical integrated LDMOS devices with a breakdown voltage of 6.5 V, available in this deep sub micron state-of-the-art CMOS process, which are driven by an inverter-chain consisting of 2 V thick-oxide devices with an active back-gate control, allowing duty-cycle adjustments to optimize the drivers efficiency. With a power consumption of 355 mW from a triple 2V, 4V and 6V power supply and a core area of 0.035 mm², a costand power-efficient alternative to typically utilized SiGe or integrated GaN solutions is presented. The proposed design was manufactured and bonded to a GaN MMIC to enable system performance evaluation. Achieving an error-free eye diagram with BER $<10^{-18}$ at the GaN MMIC output for data rates up to 4.3 GBaud.