Stacked amplifier with diode-based biasing

An integrated circuit comprising:

• an amplifier comprising a plurality of metal oxide semiconductor (MOS) transistors coupled in a stack and to receive and amplify an input signal and provide an output signal, and at least one diode-connected MOS transistor having a variable voltage drop operatively coupled in series to a gate of at least one MOS transistor in the stack, each diode-connected MOS transistor provides a variable bias voltage to an associated MOS transistor in the stack and each of the plurality of MOS transistors further biased by a common bias circuit.

A method of amplifying an input signal, comprising:

• amplifying the input signal with a plurality of transistors coupled in a stack to obtain an output signal;
• and generating at least one variable bias voltage for at least one transistor in the stack based on at least one diode having a variable voltage drop operatively coupled in series to a gate of the at least one transistor in the stack and each of the plurality of transistors further biased by a common bias circuit.

An apparatus for amplifying an input signal, comprising:

• means for amplifying the input signal to obtain an output signal, the means for amplifying comprising a plurality of transistors coupled in a stack;
• and means for generating at least one variable bias voltage for at least one transistor in the stack, the means for generating comprising at least one diode having a variable voltage drop operatively coupled in series to a gate of the at least one transistor in the stack and each of the plurality of transistors further biased by a common bias circuit.