High-Speed High-Gain CMOS OTA for SC Applications

A fast settling multipath CMOS OTA for high speed switched capacitor applications is presented here. With the basic topology similar to folded-cascode, bandwidth and DC gain of the OTA are enhanced by adding extra paths for signal from input to output. Designed circuit is simulated with HSPICE using level 49 parameters (BSIM 3v3) in 0.35mm standard CMOS technology. DC gain achieved is 56.7dB and Unity Gain Bandwidth (UGB) obtained is 1.15GHz. These results confirm that adding extra paths for signal can improve DC gain and UGB of folded-cascode significantly.

Authors:

• M.Yousefi
• A.Vatanjou
• F.Nazeri

Keywords:

• OTA (Operational Transconductance Amplifier)
• DC gain
• Unity Gain Bandwidth (UGBW)

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