US 6,982,588 B1
Inverse function method for semiconductor mixer linearity enhancement
Heng-Chih Lin, Plano, Tex. (US); Chien-Chung Chen, Plano, Tex. (US); and Ranjit Gharpurey, Ann Arbor, Mich. (US)
Assigned to Texas Instruments Incorporated, Dallas, Tex. (US)
Filed on Jun. 16, 2004, as Appl. No. 10/869,680.
Int. Cl. G06G 7/44 (2006.01); G06G 7/16 (2006.01)
U.S. Cl. 327—359 6 Claims
OG exemplary drawing
 
1. A mixer circuit comprising:
a differential rf input driver;
a differential local oscillator input circuit coupled to the differential rf input driver;
a non-linear load coupled to the differential local oscillator input circuit wherein the non-linear load compensates for non-linearity of the differential rf input driver;
wherein the non-linear load comprises a first diode-connected PMOS transistor coupled to the differential local oscillator input circuit and a second diode-connected PMOS transistor coupled to the differential local oscillator input circuit;
wherein the non-linear load further comprises two cross-coupled PMOS transistors.