A Highly Linear Low-Voltage Source-Degeneration Transconductor Based on Unity-Gain Buffer

• Published in: Tsinghua science and technology 2009-12, Vol.14 (6), p.698-702
• Main Author: 孔耀晖 刘爱荣 杨华中
• Format: Article
• Language: English
• Subjects: CMOS工艺; high linearity; low power; low voltage; transconductor; unity gain buffer; 互补金属氧化物半导体; 单位增益; 电压源; 电源电压; 缓冲器; 高线性
• ISSN: 1007-0214; 1878-7606; 1007-0214
• DOI: 10.1016/S1007-0214(09)70137-3

A complementary metal oxide semiconductor （CMOS） transconductor based on a high performance unity-gain buffer driving the degeneration resistor was used to obtain a highly linear voltage-to-current conversion with considerable reduction of the supply voltage. Simulations show that the transconductor using an 0.18-μm standard CMOS process with a 1.2-V supply voltage has less than -80 dB total harmonic distortion （THD） for a 1-MHz 0.4-Vp-p differential input signal. The third-order intermodulation is less than -63 dB for 0.25 Vp-p differential inputs at 1 MHz. The DC power consumption in the transconductor core is 240 μW. This topology is a feasible solution for low voltage and low power applications.