A 59-dB SFDR CFOA with adaptive transimpedance and driver-transistor-negative feedback for line driver in B-PLC applications

This paper presents a highly linear current-feedback operational amplifier (CFOA), featuring wide bandwidth and large amplitude for line driver in broadband power line communication (B-PLC) systems. The proposed CFOA employs an adaptive transimpedance (ATI) architecture to enhance linearity across the entire amplitude range, and a driver-transistor-negative feedback (DTNF) technique to minimize crossover distortion introduced by the output stage. The prototype of the line driver chip is fabricated in a silicon-on-insulator complementary bipolar junction transistor (SOI-CBJT) process. The measured circuit bandwidth is 120 MHz, with a DC power consumption of 276 mW under a typical supply voltage of 12 V. Measurement results show that the spurious-free dynamic range (SFDR) is 59 dB for a 16- V p p output at 1-MHz input, and 48 dB for an 8-V p p output at 12-MHz input, driving a 100- Ω load. Over the typical amplitude and frequency range of B-PLC applications, the attenuation rates are 2.43 dB/ V p p and 2.45 dB/MHz, respectively.