A 0.25-V 22-nS symmetrical bulk-driven OTA for low-frequency G_m-C applications in 130-nm digital CMOS process

This paper presents a 0.25-V supplied bulk-driven symmetrical OTA implemented in 130-nm CMOS process. By operating in weak inversion, and using a distributed layout approach, the OTA can benefit from the voltage reduction and high linearity enabled by halo-implanted transistors. The proposed circuit consumes only 10-nW, features a low transconductance of 22-nS, and a total harmonic distortion of 0.53 % for a 100-mV_pp input voltage, thus making it suitable for low-frequency and low-power (G_m) -C applications.