On-chip multiple tap transformer and inductor

• US 7,088,214 B2
• Filed: 12/04/2003
• Issued: 08/08/2006
• Est. Priority Date: 07/23/2002
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Rogougaran, Razieh, Castaneda, Jesus A., Yang, Hung Yu, Bhatti, Iqbal S.
• Primary Examiner(s): Nguyen, Tuyen T
• Application Number:
  US10/727,422
• Publication Number:
  US 20040108927A1
• Time in Patent Office: 978 Days
• Field of Search: 336/65, 336/83, 336/192, 336/200, 336/232
• US Class Current: 336/200
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• CPC Class Codes: H01F 2021/125 Printed variable inductor with taps, e.g. for VCO
• CPC Class Codes: H01F 21/12 discontinuously variable, e.g. tapped
• CPC Class Codes: H01L 27/08 including only semiconductor components of a single kind
• CPC Class Codes: H03H 7/42 Networks for transforming balanced signals into unbalanced signals and vice versa, e.g. baluns

Abstract

An on-chip multiple tap transformer balun includes a 1^st winding and a 2^nd winding having two portions. The 1^st winding is on a 1^st layer of an integrated circuit and is operably coupled for a single ended signal. The 1^st and 2^nd portions of the 2^nd winding are on a 2^nd layer of the integrated circuit. The 1^st portion of the 2^nd winding includes a 1^st node, a 2^nd node, and a tap. The 1^st node is operably coupled to receive a 1^st leg of a 1^st differential signal and the 2^nd node is coupled to a reference potential. The tap of the 1^st portion is operably coupled for a 1^st leg of a 2^nd differential signal. The 2^nd portion of the 2^nd winding includes a 1^st node, 2^nd node, and tap. The 1^st node is operably coupled to receive a 2^nd leg of the 1^st differential signal and the 2^nd node is operably coupled to the reference potential. The tap of the 2^nd portion is coupled for a 2^nd leg of the 2^nd differential signal. The 1^st and 2^nd portions of the 2^nd winding are symmetrical with respect to the 1^st and 2^nd nodes and with respect to the tap nodes.

Claims

1. An on-chip multiple tap transformer balun comprises:

first winding operably coupled for a single-ended signal; and

a second windings operably coupled for at least one of a first differential signal and a second differential signal, wherein a first portion of the second winding is symmetrical with a second portion of the second winding, and a third portion of the second winding is symmetrical with a fourth portion of the second winding, and when the first differential signal is coupled to the second winding, the first differential signal is coupled across the first portion and the second portion of the second winding, and when the second differential signal is coupled to the second winding, the second differential signal is coupled across the third portion and the fourth portion of the second winding;

wherein the second winding is electrically isolated from the first winding and electromagnetically coupled to the first winding.

2. The on-chip multiple tap transformer balun of claim 1, wherein the second winding comprises a substantially octagon interwound shape with a plurality of taps for coupling to the first and second differential signals.

3. The on-chip multiple tap transformer balun of claim 1 wherein the first winding is on at least one layer of an integrated circuit, the on-chip multiple tap transformer balun further comprises:

a shunt winding on a different layer of the integrated circuit from the at least one layer, wherein the shunt winding is coupled in parallel with the first winding.

4. The on-chip multiple tap transformer balun of claim 1, wherein the second winding further comprises:

fifth and sixths portions of the second winding operably coupled for a third differential signal, wherein the fifth portion of the second winding is symmetrical with the sixth portion of the second winding and wherein the third differential signal is coupled across the fifth portion and the sixth portion of the second winding.

5. The on-chip multiple tap transformer balun of claim 1 wherein the second winding is on at least one layer of an integrated circuit, the on-chip multiple tap transformer balun further comprises:

a shunt winding on a different layer of the integrated circuit from the at least one layer, wherein the shunt winding is connected in parallel to with the second winding.

6. The on-chip multiple tap transformer balun of claim 1 comprises:

the first winding being on a first layer of an integrated circuit;

the second winding being on a second layer of the integrated circuit, wherein the second layer is a metalization layer of the integrated circuit having lowest resistivity.

7. The on-chip multiple tap transformer balun of claim 1, wherein the first winding further comprises multiple turns.

8. The on-chip multiple tap transformer balun of claim 1, wherein the second winding further comprises:

a rectangular octagonal shape having a first dimension lengthened with respect to a square octagonal reference shape and having a second dimension shortened with respect to the square octagonal reference shape, wherein area of the rectangular octagonal shape is similar to area of the square octagonal reference shape.

9. The on-chip multiple tap transformer balun of claim 1 further comprises:

an integrated circuit size based on a balancing of inductance values of the on-chip multiple tap transformer balun, turns ratio of the on-chip multiple tap transformer balun, quality factor of the on-chip multiple tap transformer balun, and capacitance of the on-chip multiple tap transformer balun.

14. The on-chip multiple tap transformer balun of claim 1, wherein the second winding further comprises:

a rectangular octagonal shape having a first dimension lengthened with respect to a square octagonal reference shape and having a second dimension shortened with respect to the square octagonal reference shape, wherein area of the rectangular octagonal shape is similar to area of the square octagonal reference shape.

10. An on-chip multiple tap transformer balun comprises:

first winding on at least one layer of an integrated circuit, operably coupled for a single-ended signal;

a second winding operably coupled for at least one of a first differential signal and a second differential signal, wherein a first portion of the second winding is symmetrical with a second portion of the second winding, and a third portion of the second winding is symmetrical with a fourth portion of the second winding, and when the first differential signal is coupled to the second winding, the first differential signal is coupled across the first portion and the second portion of the second winding, and when the second differential signal is coupled to the second winding, the second differential signal is coupled across the third portion and the fourth portion of the second winding; and

a shunt winding on a different layer of the integrated circuit from the at least one layer, wherein the shunt winding is coupled in parallel with the first winding.

11. The on-chip multiple tap transformer balun of claim 10, wherein the second winding comprises a substantially octagon interwound shape with a plurality of taps for coupling to the first and second differential signals.

12. The on-chip multiple tap transformer balun of claim 10, wherein the second winding further comprises:

fifth and sixth portions of the second winding operably coupled for a third differential signal, wherein the fifth portion of the second winding is symmetrical with the sixth portion of the second winding and wherein the third differential signal is coupled across the fifth portion and the sixth portion of the second winding.

13. The on-chip multiple tap transformer balun of claim 10 comprises:

the first winding being on a first layer of an integrated circuit;

the second winding being on a second layer of the integrated circuit, wherein the second layer is a metalization layer of the integrated circuit having lowest resistivity.

15. An on-chip multiple tap transformer balun comprises:

first winding operably coupled for a single-ended signal;

a second winding on at least one layer of an integrated circuit, operably coupled for at least one of a first differential signal and a second differential signal, wherein a first portion of the second winding is symmetrical with a second portion of the second winding, and a third portion of the second winding is symmetrical with a fourth portion of the second winding, and when the first differential signal is coupled to the second winding, the first differential signal is coupled across the first portion and the second portion of the second winding, and when the second differential signal is coupled to the second winding, the second differential signal is coupled across the third portion and the fourth portion of the second winding; and

a shunt winding on a different layer of the integrated circuit from the at least one layer, wherein the shunt winding is coupled in parallel with the second winding.

16. The on-chip multiple tap transformer balun of claim 15, wherein the second winding comprises a substantially octagon interwound shape with a plurality of taps for coupling to the first and second differential signals.

17. The on-chip multiple tap transformer balun of claim 15, wherein the second winding further comprises:

fifth and sixth portions of the second winding operably coupled for a third differential signal, wherein the fifth portion of the second winding is symmetrical with the sixth portion of the second winding and wherein the third differential signal is coupled across the fifth portion and the sixth portion of the second winding.

18. The on-chip multiple tap transformer balun of claim 15 comprises:

the first winding being on a first layer of an integrated circuit;

the second winding being on a second layer of the integrated circuit, wherein the second layer is a metalization layer of the integrated circuit having lowest resistivity.

19. The on-chip multiple tap transformer balun of claim 15, wherein the second winding further comprises:

a rectangular octagonal shape having a first dimension lengthened with respect to a square octagonal reference shape and having a second dimension shortened with respect to the square octagonal reference shape, wherein area of the rectangular octagonal shape is similar to area of the square octagonal reference shape.