CLA-2 CO:R:C:M 089881 AJS
Mr. W.J. Dolbeer
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.
Dear Mr. Dolbeer;
This is in reply to your letter of June 27, 1991, requesting
the tariff classification of a dual surge suppressor.
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.
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
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
(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.
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.
John Durant, Director
Commercial Rulings Division