Transformer-based distributed multicore oscillator and integrated circuit and terminal thereof

A transformer-based distributed multicore oscillator, used as a millimeter wave oscillator, comprises:

• four MOS transistors M1˜M4, two transformers T1 and T2, two coarse capacitors arrays CG1 and CG2, two fine capacitors array
• s CD1 and CD2, two tail inductances Ltail1 and Ltail2;
• wherein a first cross-coupled transistors pair is consisted by two MOS transistors M1 and M2, a second cross-coupled transistors pair is consisted by two MOS transistors M3 and M4;
• the two transformers T1 and T2 are set symmetrically with two inner coils Ld being defined inside and two outer coils Lg being defined outside;
• the two transformers T1 and T2 have the same construction and the same turns ratio of 1:1 between the inner coil Ld and the outer coil Lg;
• the inner coil Ld of the transformer T1, the fine capacitors array CD1, the inner coil Ld of the transformer T2, the fine capacitors array CD2 are connected in series successively;
• the outer coil Lg of the transformer T1, the coarse capacitors array CG1, the outer coil Lg of the transformer T2, the coarse capacitors array CG2 are connected in series successively;
• the two inner coils Ld are cross-linked;
• two drain regions of two MOS transistors M1 and M2 are connected with two ends of the fine capacitors array CD1 respectively, two drain regions of two MOS transistors M3 and M4 are connected with two ends of the fine capacitors array CD2 respectively;
• two grid regions of two MOS transistors M1 and M2 are connected with two ends of the coarse capacitors array CG1 respectively, two grid regions of two MOS transistors M3 and M4 are connected with two ends of the coarse capacitors array CG2 respectively;
• two source regions of two MOS transistors M1 and M3 are both connected to a ground VSS via the tail inductances Ltaii, two source regions of two MOS transistors M2 and M4 are both connected to the ground VSS via the tail inductances Ltail2 taps of the two transformers T1 and T2 are connected with a voltage source Vdd;
• two signal output ports are defined by two drain regions of any two MOS transistors from the two cross-coupled transistors pairs;
• the layout of the oscillator is designed as follows:
• a cross-coupled unit being defined by the two cross-coupled transistors pairs, and the two cross-coupled transistors pairs being adjacent and being set in centre of the layout;
• the two transformers T1 and T2 being set on the periphery of the cross-coupled unit;
• all capacitors arrays being set on the periphery of the cross-coupled unit, and the coarse capacitors arrays being outerside, the fine capacitors arrays being inside;
• a NT_N layer being arranged in a annular region distributed by the two transformers T1 and T2;
• the cross-coupled unit being located inside of the annular region and being out of touch with the NT_N layer;
• all capacitors arrays being located outside of the annular region.