Title :
300mV 50kHz 75.9dB SNDR CT ΔΣ Modulator with Inverter-based Feedforward OTAs
Author :
Lishan Lv ; Qiang Li
Author_Institution :
Integrated Syst. Lab., Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
A low voltage low power continuous-time (CT) ΔΣ modulator is presented. To obtain a high linearity and power efficient modulator, a novel inverter-based feedforward OTA is proposed. A gain-enhancement technique is utilized to relax the load effect. With a novel complementary differential-difference common mode feedback circuit, the CMRR of OTA achieves 81.8 dB. The circuits were implemented in a 0.13 μm CMOS technology. The post layout simulation demonstrates that the modulator consumes 29.58 μW from a 300 mV supply and achieves a peak SNDR of 75.9 dB, a dynamic range of 79.5 dB, with a 50 kHz bandwidth under 64 oversampling ratio.
Keywords :
CMOS integrated circuits; feedforward; invertors; operational amplifiers; sigma-delta modulation; 0.13 μm CMOS technology; CMRR; SNDR CT ΔΣ modulator; complementary differential-difference common mode feedback circuit; frequency 50 kHz; gain-enhancement technique; high linearity modulator; inverter-based feedforward OTA; low voltage low power continuous-time ΔΣ modulator; oversampling ratio; post layout simulation; power 29.58 muW; power efficient modulator; voltage 300 mV; Feedforward neural networks; Gain; Inverters; Linearity; Low voltage; Modulation; Transistors;
Conference_Titel :
Circuits and Systems (ISCAS), 2015 IEEE International Symposium on
Conference_Location :
Lisbon
DOI :
10.1109/ISCAS.2015.7168633
