Quasi Rail-to-Rail Very Low-Voltage OPAMP With a Single pMOS Input Differential Pair.

In this brief, a quasi-rail-to-rail low-voltage operational amplifier ( V_DD- V_SS- V_DSATP- V_DSATN) is introduced. A common-mode adapter that uses the common-mode voltage present at the common-source node of the available differential pair to accommodate the large common-mode input signal is proposed. The common-mode adapter operates properly at 300 kHz while driving a load capacitor of 15 pF and employs only 95 μW of static power. The amplifier was fabricated in a standard AMI 0.5-μm CMOS process (V_tn = 0.7 V and V_tp = -0.9 V) and achieves an IM3 of - 48 dB at 300 kHz for a two-tone input signal of 0.8 V_pk-_pk. A 1-V total supply voltage was used. [ABSTRACT FROM AUTHOR]