Enhanced slew rate, constant-gm rail-to-rail OpAmp using 1:2 current mirror biasing technique

A constant-gm, rail-to-rail operational amplifier circuit topology is presented in this paper. The amplifier input stage is realized using single NMOS pair at 0.13μm bulk-CMOS process technology. The overall gain variation is within the range of ±2.338% for the rail-to-rail common mode input range. The proposed design is able to reject the common mode input response with 115dB of common mode rejection ratio (CMRR). High slew rate is achieved and the simulated value is +19/−43 (V/μs) of an unity gain buffer op-amp at 5pF of CL. The variation in overall gm and gain are also simulated at different corner temperatures. The circuit simulation is done in Tanner EDA at 1.8 V of power supply which dissipates the power of 6.1mW.

[1]  J. Francisco Duque-Carrillo,et al.  Transconductance enhancement in bulk-driven input stages and its applications , 2011 .

[2]  Edgar Sánchez-Sinencio,et al.  A constant-g/sub m/ rail-to-rail op amp input stage using dynamic current scaling technique , 2005, 2005 IEEE International Symposium on Circuits and Systems.

[4]  G. Torelli,et al.  1-V rail-to-rail bulk-driven CMOS OTA with enhanced gain and gain-bandwidth product , 2005, Proceedings of the 2005 European Conference on Circuit Theory and Design, 2005..

[5]  C.-W. Lu,et al.  1 V rail-to-rail constant-g m CMOS op amp , 2009 .

[6]  Shouli Yan,et al.  Novel and robust constant-g/sub m/ technique for rail-to-rail CMOS amplifier input stages , 2005, 2005 IEEE International Symposium on Circuits and Systems.

[7]  Rasoul Dehghani,et al.  A process and temperature robust constant-gm input/output rail-to-rail op-amp , 2015, Microelectron. J..

[8]  J.L. Ausin,et al.  Constant-g/sub m/ constant-slew-rate high-bandwidth low-voltage rail-to-rail CMOS input stage for VLSI cell libraries , 2003, Proceedings of the 2003 International Symposium on Circuits and Systems, 2003. ISCAS '03..

[9]  Khayrollah Hadidi,et al.  A 1.5-V, Constant-Gm, Rail-to-Rail Input Stage Operational Amplifier , 2006, 2006 13th IEEE International Conference on Electronics, Circuits and Systems.

[10]  Boram Lee,et al.  1.2V constant-gm rail-to-rail CMOS Op-Amp input stage with new overlapped transition regions technique for ECG amplifier , 2013, 2013 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC).

[11]  Johan H. Huijsing,et al.  Low-voltage operational amplifier with rail-to-rail input and output ranges , 1989 .

[12]  Shouli Yan,et al.  A Robust Rail-to-Rail Input Stage with Constant-gm and Constant Slew Rate Using a Novel Level Shifter , 2007, 2007 IEEE International Symposium on Circuits and Systems.

[13]  Jonny Johansson,et al.  Constant gm, rail-to-rail input transconductance stage with output common mode current compensation , 2006, 2006 13th IEEE International Conference on Electronics, Circuits and Systems.

[14]  Edgar Sanchez-Sinencio,et al.  A rail-to-rail amplifier input stage with ±0.35%g m fluctuation. , 2005 .