Ultra low-voltage CMOS transconductance amplifiers

Simple and symmetrical ultra low-voltage current mode analog circuits and autozeroing amplifiers are presented. The low-voltage analog circuits are based on low-voltage inverters resembling precharge digital logic. Ultra low-voltage analog circuits can be operated at supply voltages down to 250?mV with rail-to-rail input and output swing. The output current of the ultra low-voltage symmetrical transconductance amplifier can be quite large due to a current boost technique. Ultra low-voltage analog circuits can be operated at supply voltages down to 250?mV with rail- to-rail input and output swing. The current headroom is 3???A and the supply voltage is 300?mV. For supply voltages down to 300?mV simulated data shows that the maximum clock frequency is approximately 600?MHz.