An 87% Power-Efficiency Hybrid of Voltage- and Current-Mode Line Driver with an Adaptive Amplitude Tuning

Abstract

This brief presents a hybrid of voltage- and current-mode line drivers for the turbo controller area network (CAN). The current-mode scheme prevents signal attenuation caused by source termination resistors, and it enhances signal power efficiency. On top of that, an adaptive amplitude tuning is implemented to mitigate non-linearity and closed-loop gain variations against load impedance variations. The proposed line driver achieves 87.0% power-efficiency and total harmonic distortion, plus noise (THD+N) of -49.0 dB at an input frequency of 40 MHz and output swing of 2.8 V-PP differential. The adaptive amplitude tuning allows load impedance variations from 80 Omega to 160 Omega. The total power consumption is 37.6 mW with a 1.8 V supply voltage in 180 nm CMOS, and it occupies 0.377 mm(2).