CLA-2 CO:R:C:M 089881 AJS

Mr. W.J. Dolbeer
Manager-Contracts
Avex Electronics Inc.
4807 Bradford Drive
Huntsville, Alabama 35805

RE: Dual surge suppressor; Heading 8536; Heading 8541; Chapter 85, note 5(b)(iii); Van Nostrand's Scientific Encyclopedia; Basic Electronics Theory, with Projects and Experiments; IEEE Standard Dictionary of Electrical and Electronics Terms; Subheading 8541.10.00; ENs 85.41 (A)(I); Subheading 8542.11.00; Chapter 85, note 5(b)(i); Chapter 85, note 5; ENs 85.36(c); H. Conf. Rep. No. 576.

Dear Mr. Dolbeer;

This is in reply to your letter of June 27, 1991, requesting the tariff classification of a dual surge suppressor.

FACTS:

The merchandise at issue is a dual surge suppressor (DSS). It is a molded module containing two back-to-back zener diodes with one lead common to both. The DSS can be used as a limitor, pulse shaper or a clipper in applications where a dual unit could be utilized with a common ground.

ISSUE:

Whether the DSS is properly classifiable within heading 8536, Harmonized Tariff Schedule of the United States (HTSUS), which provides for "[e]lectrical apparatus for switching or protecting electrical circuits, or making connections to or in electrical circuits (for example, switches, relays, fuses, surge suppressors, plugs, sockets, lamp-holders, junction boxes), for a

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voltage not exceeding 1,000 V."; or classifiable within heading 8541, HTSUS, which provides for diodes; or classifiable within heading 8542, HTSUS, which provides for electronic integrated circuits and microassemblies.

LAW AND ANALYSIS:

Heading 8542, HTSUS, provides for electronic micro- assemblies. These are microassemblies of the molded module, micromodule or similar types, consisting of discrete, active or both active and passive, components which are combined and interconnected. Chapter 85, note 5(b)(iii). The DSS satisfies this description. It is a molded module consisting of two zener diodes (i.e., active components) which are interconnected to a common lead. A zener diode is a type of silicon diode. Van Nostrand's Scientific Encyclopedia (VN), 7th ed., p. 3062, vol. II (1988). See also Delton T. Horn, Basic Electronics Theory, with Projects & Experiments, p. 228 (1981); IEEE Standard Dictionary of Electrical and Electronics Terms, p. 653 (1972). Zener diodes act like rectifiers until the applied voltage reaches the avalanche breakdown voltage (zener voltage). VN p. 3062. At this point, the diode becomes conducting. VN p. 3062. They are used in voltage-limiting and power supplies. VN p. 3062. Accordingly, the subject DSS satisfies the terms of heading 8542, HTSUS. More specifically, the DSS is described within subheading 8542.80.00, HTSUS, as an "other" electronic integrated circuit and microassembly.

You request classification of the DSS within subheading 8541.10.00, HTSUS, which provides for diodes. Diodes are described as two-terminal devices with a single p n junction. Harmonized Commodity Description and Coding System Explanatory Notes (ENs) 85.41 (A)(I), p. 1397. While a zener diode itself satisfies this description, the subject DSS does not satisfy this description. The DSS is not merely a two-terminal device with a single p n junction. It consists of two two-terminal devices interconnected to a common lead in a molded module. You claim that this distinction is not substantive. However, heading 8542, HTSUS, specifically provides for molded modules consisting of diodes which are combined and interconnected. Therefore, the fact that an article contains two diodes instead of one is substantive. Consequently, the subject DSS is not classifiable within heading 8541, HTSUS, as merely a diode.

You also request classification of the DSS within subheading 8542.11.00, HTSUS, which provides for digital monolithic integrated circuits. These are described as circuits in which the circuit elements (diodes, transistors, resistors, capacitors, interconnections, etc.) are created in the mass

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(essentially) and on the surface of a semiconductor material (doped silicon, for example) and are inseparably associated. Chapter 85, note 5(b)(i). The subject DSS does not satisfy this description. It does not consist of diodes created in the mass and on the surface of a semiconductor material. The diodes are created separately and interconnected within the DSS. In addition, the diodes in the DSS are not inseparably associated. They are separate back-to-back diodes connected to a common lead. Thus, the DSS does not satisfy the terms of this subheading and cannot be classified therein.

Heading 8536, HTSUS, provides for electrical apparatus for protecting electrical circuits. It is stated that this device was previously classified under subheading 8536.30.00, HTSUS. Surge suppressors are listed as an exemplar of devices classifi- able within heading 8536, HTSUS. As stated previously, the DSS is a microassembly described within heading 8542, HTSUS. For the classification of microassemblies, heading 8542 takes precedence over any other heading in the tariff schedule which might cover microassemblies by reference to, in particular, their function. Chapter 85, note 5. The subject DSS satisfies this description. While it performs the function of a surge suppressor, it is a microassembly described within heading 8542, HTSUS. Accordingly, the DSS is precluded from classification within heading 8536, HTSUS, by the application of this legal note.

This conclusion is also supported by the ENs to heading 85.36. They state that this heading excludes the semiconductor diodes of heading 85.41 used as voltage controllers. ENs 85.36 (c). The subject DSS consists of semiconductor diodes used as a voltage controller. While the ENs are not dispositive, they provide a commentary on the scope of each heading, and offer guidance for interpretation of the HTSUS. H. Conf. Rep. No. 576, 100th Cong., 2d Sess., p. 549, reprinted in 1988 U.S. CODE CONG. & ADMIN. NEWS p. 1582. Accordingly, we find this language instructive in determining that the subject DSS is not classifiable within heading 8536, HTSUS.

HOLDING:

The subject DSS is classifiable within 8542.80.00, HTSUS, which provides for "other" electronic integrated circuits and microassemblies dutiable at the General Column 1 rate of 3.9 percent ad valorem.


Sincerely,


John Durant, Director
Commercial Rulings Division