Lumped Elements for RF and Microwave Circuits phần 8 pps

Transformers and Baluns 349

Figure 11.24 shows the simulated and measured performance of a planar￾transformer balun. The amplitude and phase imbalances between the two bal￾anced ports are less than 1.5 dB and 10 degrees, respectively, over the 1.5- to

6.5-GHz frequency band. The simulated results shown were obtained using

EM analysis.

We have described several kinds of transformers in this chapter. The

selection of a particular type depends on the application, performance, and cost

limitations.

Figure 11.24 Comparison between simulated and measured performances of a planar-trans￾former balun. (From: [24].  1991 IEEE. Reprinted with permission.)

References

[1] Balabanian, N., Fundamentals of Circuit Theory, Boston, MA: Allyn and Bacon, 1961.

[2] RF Transformer Designer’s Guide, Brooklyn, NY: Mini Circuits.

[3] van der Puije, P. D., Telecommunication Circuit Design, New York: John Wiley, 1992.

[4] Sevick, J., Transmission Line Transformers, Atlanta, GA: Noble Publishing, 1996.

350 Lumped Elements for RF and Microwave Circuits

[5] Abrie, P. D., Design of RF and Microwave Amplifiers and Oscillators, Norwood, MA: Artech

House, 1999.

[6] Mongia, R., I. Bahl, and P. Bhartia, RF and Microwave Coupled-Line Circuits, Norwood,

MA: Artech House, 1999, Chaps. 10, 11.

[7] Davis, W. A., and K. K. Agarwal, Radio Frequency Circuit Design, New York: John Wiley,

2001.

[8] Trask, C., ‘‘Wideband Transformers: An Intuitive Approach to Models, Characterizations

and Design,’’ Applied Microwave Wireless, November 2001, pp. 30–41.

[9] Song, B. W., S. J. Kim, and H. Y. Lee, ‘‘Vertical Integrated Transformers Using Bondwires

for MMICs,’’ IEEE MTT-S Int. Microwave Symp. Dig., 2000, pp. 1341-1344.

[10] Niclas, K. B., R. R. Pereira, and A. P. Chang, ‘‘Transmission Lines Accurately Model

Autotransformers,’’ Microwaves and RF, Vol. 31, November 1992, pp. 67–75.

[11] Krauss, H. L., C. W. Bostian, and F. H. Raab, Solid State Radio Engineering, New York:

John Wiley, 1980, Chap. 12.

[12] Rotholz, E., ‘‘Transmission-Line Transformers,’’ IEEE Trans. Microwave Theory Tech.,

Volume MTT-29, April 1981, pp. 327–331.

[13] Martin, M., ‘‘Ferrite Transformers Minimize Losses in RF Amplifiers,’’ Microwave and

RF, Vol. 29, May 1990, pp. 117–126.

[14] MacDonald, M., ‘‘Design Broadband Passive Components with Ferrites,’’ Microwaves and

RF, Vol. 32, October 1993, pp. 81–132.

[15] McClure, D. A., ‘‘Broadband Transmission-Line Transformer Family Matches a Wide

Range of Impedances,’’ RF Design, February 1994, pp. 62–66.

[16] Hamilton, N., ‘‘RF Transformers Part I: The Windings,’’ RF Design, June 1995,

pp. 36–44.

[17] Carpentieri, E., ‘‘Model Characterizes Transmission-Line Transformers,’’ Microwaves and

RF, Vol. 35, November 1996, pp. 73–80.

[18] Carpentieri, E., ‘‘Equations Model Transmission-Line Transformers,’’ Microwaves and RF,

Vol. 36, June 1997, pp. 94–98.

[19] Long, J. R., ‘‘Monolithic Transformers for Silicon RF IC Design,’’ IEEE J. Solid-State

Circuits, Vol. 35, September 2000, pp. 1368–1381.

[20] Ferguson, D., et al., ‘‘Transformer Coupled High-Density Circuit Technique for MMIC,’’

IEEE GaAs IC Symp. Dig., 1984, pp. 34–36.

[21] Howard, G. E., et al., ‘‘The Power Transfer Mechanism of MMIC Spiral Transformers

and Adjacent Spiral Inductors,’’ IEEE MTT-S Int. Microwave Symp. Dig., 1989,

pp. 1251–1254.

[22] Boulouard, A., and M. LeRouzic, ‘‘Analysis of Rectangular Spiral Transformers for MMIC

Applications,’’ IEEE Trans. Microwave Theory Tech., Vol. 37, August 1989, pp. 1257–1260.

[23] Chow, Y. L., G. E. Howard, and M. G. Stubbs, ‘‘On the Interaction of the MMIC and

its Packaging,’’ IEEE Trans. Microwave Theory Tech.,Vol. 40, August 1992, pp. 1716–1719.

Transformers and Baluns 351

[24] Chen, T-H, et al., ‘‘Broadband Monolithic Passive Baluns and Monolithic Double￾Balanced Mixer,’’ IEEE Trans. Microwave Theory Tech., Vol. 39, December 1991,

pp. 1980–1986.

[25] Marx, K. D., ‘‘Propagation Modes, Equivalent Circuits, and Characteristic Terminations

for Multiconductor Transmission Lines with Inhomogeneous Dielectrics,’’ IEEE Trans.

Microwave Theory Tech., Vol. MTT-21, July 1973, pp. 450–457.

[26] Djordjevic, A., et al., Matrix Parameters for Multiconductor Transmission Lines, Norwood,

MA: Artech House, 1989.

12

Lumped-Element Circuits

Lumped elements have been in use in microwave circuits for more than 30

years. This chapter deals exclusively with these circuits where lumped elements,

in addition to size reduction, provide distinct benefits in terms of bandwidth

and electrical performance. Such circuits are classified into two categories: passive

circuits and control circuits, as discussed in this chapter.

12.1 Passive Circuits

12.1.1 Filters

The basic theory of filters [1–10] is based on a combination of lumped elements

such as inductors and capacitors as shown in Figure 12.1. This configuration

is a lowpass filter, and we can develop a prototype design with 1-V input–output

impedance and a 1-rad cutoff frequency. From here, it is simply a matter of

scaling the g values for various elements to obtain the desired frequency response

and insertion loss. In addition, other filter types such as highpass, bandpass,

and band-stop merely require a transformation in addition to the scaling to

obtain the desired characteristics.

At RF frequencies and the lower end of the microwave frequency band,

filters have been realized using lumped elements (chip/coil inductors and parallel

plate chip capacitors) and employ printed circuit techniques or PCBs to connect

them. Several hybrid MIC technologies such as thin film, thick film, and cofired

ceramic are being used to develop such circuits. Lumped-element filters can be

implemented easily, and using currently available surface-mounted components

one can meet size and cost targets in high-volume production. Due to the low

353