(12) United States Patent Cuk (45) Date of Patent: *Oct ... · Laguna Hills, CA (US) 92653 R.D. Middlebrook and Slobodan Cuk, A General Uni?ed Approach to Modelling Switching—Converter

US006304460B1

(12) United States Patent Cuk

(10) Patent N0.: (45) Date of Patent:

US 6,304,460 B1 *Oct. 16, 2001

(54)

(76)

(21) (22) (51)

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SWITCHING DC-TO-DC CONVERTER 5,790,005 8/1998 Santi et a1. . UTILIZING A SOFT SWITCHING 5,838,552 * 11/1998 Fraidlin et a1. ...................... .. 363/16 TECHNIQUE 5,999,417 * 12/1999 Schlecht ............................... .. 363/16

OTHER PUBLICATIONS Inventor: Slobodan Cuk, 27682 Gold Dust,

Laguna Hills, CA (US) 92653 R.D. Middlebrook and Slobodan Cuk, A General Uni?ed Approach to Modelling Switching—Converter Power Stages,

NOIiCeI This patent issued on a Continued PIOS- California Institute of Technology, PESC 76 Record, pp. ecution application ?led under 37 CFR 18_34 No date, 1.53(d), and 15 Subject I0 the twenty year Akio Nakamura, Junpei Ohta, “A New Reverse—Biased patent term provisions of 35 USC- Choke Coil”, TDK—Electronics Company Ltd., Tokyo, 154(21)(2)- Japan, Proceedings of Powercom 9, 1982, pp. 1—7 No

month. subleet_to any diselaimeri the term of this Satoshi Frank Shiraki, “Reducing Magnetic Component Patent 15 extended or adlusted under 35 SiZe with Reversed Biased Ferrite Core,” Hitachi Magnetics U-S~C~ 154(k)) by 12 days- Coporation, Edmore, Michigan, pp. 1—5 No date.

Appl. N0.: 09/566,045 * Cited by examiner

- _ Primary Examiner—Peter S. Wong F l d. M 5 2000 1 e ay ’ Assistant Examiner—Bao Q. Vu

Int. Cl.7 ......................... .. H02M 3/335; H02M 1/12; (74) Attorney, Agent, or Firm—A. M. Fernandez H02M 1/14

US. Cl. ............................... .. 363/16; 363/41; 363/55; (57) ABSTRACT

363/131 Soft switching DC-to-DC converter achieves simulta Field Of Search ................................ .. 363/16, 40, 55, neously ultra high ef?ciency and very small siZe owing to a

363/95, 97, 131, 41 new magnetic circuit structure and a corresponding novel _ converter circuit con?guration with special properties.

References Clted Unique magnetic design also provides an overload current

Us PATENT DOCUMENTS capability 'of several times the nominal load current. Despite its simple implementation requiring only proper drive timing

4,184,197 1/1980 Cuk et a1. . of the switching devices, the unique soft-switching methods 4,257,087 3/1981 Cuk- result in nearly complete elimination of switching losses 5,027,264 : 6/1991 DeDoncker et a1. ................ .. 363/16 Over the entire Operating range_ This, in mm, permits Opera_

DeDoncker Ct 8.1. ................ .. tion at even Switching frequencies, and leads to 5,166,869 11/1992 Hesterman. fu th d t. . . d . ht 5,313,382 * 5/1994 Farrington ............................ .. 363/16 r er re ‘16 10“ 1“ SlZe an Welg '

5,416,387 * 5/1995 Cuk et a1. ...................... .. 315/209 R

5,539,630 7/1996 Pietkiewicz et a1. . 82 Claims, 73 Drawing Sheets

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Fig. 1a (Prior Art)

ON OFF

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U.S. Patent 061. 16, 2001 Sheet 3 6f 73 US 6,304,460 B1

C A .w. + C D m.

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Fig. 3b (Prior Art)

U.S. Patent 061. 16, 2001 Sheet 4 6f 73 US 6,304,460 B1

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U.S. Patent Oct. 16, 2001 Sheet 5 6f 73 US 6,304,460 B1

Fig. 6a (Prior Art)

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U.S. Patent 061. 16, 2001 Sheet 6 6f 73 US 6,304,460 B1

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U.S. Patent 061. 16, 2001 Sheet 7 6f 73 US 6,304,460 B1

Fig. 8a (Prior Art)

Fig. 9a W92 N(l1+ '2) Ni (Prior Art) Fig 9b

U.S. Patent 061. 16, 2001 Sheet 8 6f 73 US 6,304,460 B1

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Fig. 10b (Prior Art)

U.S. Patent 061. 16, 2001 Sheet 9 6f 73 US 6,304,460 B1

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Fig. 11a (Prior Art)

Fig. 11b

U.S. Patent 0a. 16, 2001 Sheet 10 6f 73 US 6,304,460 B1

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U.S. Patent 061. 16, 2001 Sheet 11 6f 73 US 6,304,460 B1

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U.S. Patent 061. 16, 2001 Sheet 15 6f 73 US 6,304,460 B1

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U.S. Patent 061. 16, 2001 Sheet 16 6f 73 US 6,304,460 B1

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U.S. Patent 061. 16, 2001 Sheet 17 6f 73 US 6,304,460 B1

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U.S. Patent 061. 16, 2001 Sheet 18 6f 73 US 6,304,460 B1

Fig. 20a

Fig. 20b

U.S. Patent 061. 16, 2001 Sheet 19 6f 73 US 6,304,460 B1

Fig. 21