Title :
A new implementation of constant-gm op amp input stage for CMOS low voltage applications
Author :
Hwang, Changku ; Motamed, Ali ; Ismail, Mohammed
Author_Institution :
Dept. of Electr. Eng., Ohio State Univ., Columbus, OH, USA
Abstract :
In this paper we propose a new implementation method for the design of op amp input stage with rail-to-rail constant-gm. The new implementation is based on processing signal currents rather than handling DC tail currents. As a result, it is universal in that the constant-gm can be obtained independent of input transistor types (MOS or bipolar) and their operating regions (weak or strong inversion for MOS and active for bipolar). To demonstrate the idea, a new MOS-type input stage has been designed with a 2-μm CMOS process and simulation results of input stage transconductance are provided. The common mode input voltage can even exceed the positive and the negative rails by 300 mV
Keywords :
CMOS analogue integrated circuits; integrated circuit design; operational amplifiers; 2 micron; CMOS LV applications; constant transconductance input stage; implementation method; input stage transconductance; op amp input stage; signal current processing; Circuits; Design methodology; Equations; Low voltage; MOSFETs; Microelectronics; Rail to rail inputs; Signal processing; Tail; Transconductance;
Conference_Titel :
Circuits and Systems, 1995., Proceedings., Proceedings of the 38th Midwest Symposium on
Conference_Location :
Rio de Janeiro
Print_ISBN :
0-7803-2972-4
DOI :
10.1109/MWSCAS.1995.510344
