The current efficiency of MOS transconductance amplifiers

The current efficiency of several amplifiers is studied using the IDAC amplifier synthesis program. The possibilities and features of IDAC are briefly discussed and some important simulation results are presented. A current excess factor is defined to compare performance independently of gain-bandwidth product and capacitive load. Experimental results of integrated amplifiers are compared with the performances predicted by IDAC and SPICE2. Finally, it is shown how the current efficiency can be further improved.