Low voltage bulk driven OTA with enhanced transconductance and dc gain
A novel low voltage bulk driven operational transconductance amplifier (OTA) with enhanced transconductance and dc gain is presented. Based on the current recycling structure and partial positive feedback technique, the effective transconductance of the bulk driven input stage is improved. Also, the bulk biasing technique is proposed to the composite transistor to achieve the dc gain enhancement. The proposed OTA is designed to operate with a 1 V supply using the CSMC 0.18 um CMOS process. Results confirm that the gain bandwidth achieves 29.6 MHz and the dc gain is higher than 86.1 dB when the load is 25.0 pF. The figure of merit is above 370, which demonstrates the proposed OTA has a significant boost compared to prior arts.