Patent ID: 7508264

Claim:
An RF amplifier including N gain stages, the RF amplifier comprising: an Nth gain stage including: a first inductor and a first gain transistor connected in series between a first voltage source and a second voltage source; and a second inductor and a second gain transistor connected in series between the first voltage source and the second voltage source; and an N−1 gain stage including: a third gain transistor and a third inductor connected in series between the first voltage source and a first bias node; a fourth gain transistor and a fourth inductor connected in series between the first voltage source and the first bias node; and a first bias transistor connected between the first bias node and the second voltage source, the first bias transistor having a gate connected to the first bias node, wherein the first gain transistor, the second gain transistor, and the first bias transistor are first type transistors, wherein the third gain transistor and the fourth gain transistor are second type transistors, wherein a first node between the first inductor and the first gain transistor provides a negative differential output signal, wherein a second node between the second inductor and the second gain transistor provides a positive differential output signal, wherein a third node between the third gain transistor and the third inductor directly drives a gate of the first gain transistor, and wherein a fourth node between the fourth gain transistor and the fourth inductor directly drives a gate of the second gain transistor.