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 22nm FDSOI CMOS process, generating an output voltage swing of 6V for GaN-based switching power amplifier with an estimated capacitive load impedance of 0.35 pF. This is achieved by utilizing integrated LDMOS devices with a breakdown voltage of 6.5V, available in this CMOS process, which are driven by an inverter-chain consisting of 2V thick-oxide devices with an active back-gate control, allowing duty-cycle adjustments to optimize the drivers efficiency. With a power consumption of 355mW from a triple 2V, 4V and 6V power supply and a core area of 0.035m2, a cost- and power-efficient alternative to 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 for data rates up to 4.3 GBaud.