Patent ID: 7139547

Claim:
An integrated tuner, comprising: a substrate; a signal input on said substrate; a local oscillator (LO) generation circuit, disposed on said substrate, that is configured to generate a differential local oscillator signal; a differential direct conversion mixer, disposed on said substrate, and coupled to said signal input and said differential LO oscillator signal; a differential tunable lowpass filter, disposed on said substrate, and coupled to an output said differential direct conversion mixer; and a LO correction circuit, coupled between said LO generation circuit and said differential direct conversion mixer, that is configured to adjust an amplitude level of said differential LO oscillator signal to improve performance of said differential direct conversion mixer, said LO correction circuit including a variable amplifier that variably amplifies said differential local oscillator signal according to a control signal; and a level detect circuit, connected to the output of said variable amplifier, that generates said control signal based on an output level of said variable amplifier.