Manual of U.S. Patent Classification
as of June 30, 2000

Class
326
ELECTRONIC DIGITAL LOGIC CIRCUITRY

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Subclass		Title
ClassTitle		===> ELECTRONIC DIGITAL LOGIC CIRCUITRY
1		SUPERCONDUCTOR (E.G., CRYOGENIC, ETC.)
2		. Tunneling device
3		. . Josephson tunneling device
4		. . . Plural devices (e.g., distributive device, etc.)
5		. . . Interference device (i.e., SQUID)
6		. . Function of AND, OR, NAND, NOR, or NOT
7		. Function of AND, OR, NAND, NOR, or NOT
8		SECURITY (E.G., ACCESS OR COPY PREVENTION, ETC.)
9		RELIABILITY
10		. Redundant
11		. . Voter circuit (e.g., majority logic, etc.)
12		. . With flip-flop
13		. . With field effect-transistor
14		. Fail-safe
15		. Parasitic prevention in integrated circuit structure
16		WITH TEST FACILITATING FEATURE
17		ACCELERATING SWITCHING
18		. Bipolar transistor
19		. . With Schottky device
20		. . . Complementary transistors
21		SIGNAL SENSITIVITY OR TRANSMISSION INTEGRITY
22		. Input noise margin enhancement
23		. . With field effect-transistor
24		. . . Complementary FET`s
25		. . . Depletion or enhancement
26		. Output switching noise reduction
27		. . With field effect-transistor
28		. . . With clocking
29		. Pulse shaping (e.g., squaring, etc.)
30		. Bus or line termination (e.g., clamping, impedance matching, etc.)
31		. Signal level or switching threshold stabilization
32		. . Temperature compensation
33		. . Bias or power supply level stabilization
34		. . With field effect-transistor
35		THRESHOLD (E.G., MAJORITY, MINORITY, OR WEIGHTED INPUTS, ETC.)
36		. With field effect-transistor
37		MULTIFUNCTIONAL OR PROGRAMMABLE (E.G., UNIVERSAL, ETC.)
38		. Having details of setting or programming of interconnections or logic functions
39		. Array (e.g., PLA, PAL, PLD, etc.)
40		. . With flip-flop or sequential device
41		. . Significant integrated structure, layout, or layout interconnections
42		. . Bipolar transistor
43		. . . Emitter-coupled logic or emitter-follower logic
44		. . Field effect transistor
45		. . . Complementary FET`s
46		. Sequential (i.e., finite state machine) or with flip-flop
47		. Significant integrated structure, layout, or layout interconnections
48		. Bipolar transistor
49		. Field-effect transistor
50		. . Complementary FET`s
51		INHIBITOR
52		EXCLUSIVE FUNCTION (E.G., EXCLUSIVE OR, ETC.)
53		. Half-adder or quarter-adder
54		. Exclusive NOR
55		. With field-effect transistor
56		TRI-STATE (I.E., HIGH IMPEDANCE AS THIRD STATE)
57		. With field effect-transistor
58		. . Complementary FET`s
59		THREE OR MORE ACTIVE LEVELS (E.G., TERNARY, QUATENARY, ETC.)
60		. With conversion (e.g., three level to two level, etc.)
61		INSULATED GATE CHARGE TRANSFER DEVICE
62		INTERFACE (E.G., CURRENT DRIVE, LEVEL SHIFT, ETC.)
63		. Logic level shifting (i.e., interface between devices of different logic families)
64		. . Bi-CMOS
65		. . . TTL to/from CMOS
66		. . . ECL to/from CMOS
67		. . . ECL to/from TTL
68		. . Field-effect transistor (e.g., JFET, MOSFET, etc.)
69		. . . ECL to/from GaAs FET (e.g., MESFET, etc.)
70		. . . TTL to/from MOS
71		. . . . TTL to/from CMOS
72		. . . . . Using depletion or enhancement transistors
73		. . . ECL to/from MOS
74		. . . ECL to/from TTL
75		. . Bipolar transistor
76		. . . TTL to/from MOS
77		. . . ECL to/from MOS
78		. . . ECL to/from TTL
79		. . . Integrated Injection Logic (I2L)
80		. Supply voltage level shifting (i.e., interface between devices of a same logic family with different operating voltage levels)
81		. . CMOS
82		. Current driving (e.g., fan in/out, off chip driving, etc.)
83		. . Field-effect transistor
84		. . . Bi-CMOS
85		. . . . Having plural output pull-up or pull-down transistors
86		. . . Bus driving
87		. . . Having plural output pull-up or pull-down transistors
88		. . . With capacitive or inductive bootstrapping
89		. . Bipolar transistor
90		. . . Bus driving
91		. . . Having plural output pull-up or pull-down transistors
92		. . . With capacitive or inductive bootstrapping
93		CLOCKING OR SYNCHRONIZING OF LOGIC STAGES OR GATES
94		. Metastable state prevention
95		. Field-effect transistor
96		. . Two or more clocks (e.g., phase clocking, etc.)
97		. . . MOSFET
98		. . MOSFET
99		HAVING LOGIC LEVELS CONVEYED BY SIGNAL FREQUENCY OR PHASE
100		INTEGRATED INJECTION LOGIC
101		SIGNIFICANT INTEGRATED STRUCTURE, LAYOUT, OR LAYOUT INTERCONNECTIONS
102		. Field-effect transistor
103		. . Complementary FET`s
104		FUNCTION OF AND, OR, NAND, NOR, or NOT
105		. Decoding
106		. . With field-effect transistor
107		. . . Depletion or enhancement
108		. . . CMOS
109		. Bipolar and FET
110		. . Bi-CMOS
111		. Space discharge device (e.g., vacuum tube, etc.)
112		. Field-effect transistor (e.g., JFET, etc.)
113		. . Pass transistor logic or transmission gate logic
114		. . Wired logic (e.g., wired-OR, wired-AND, dotted logic, etc.)
115		. . Source-coupled logic (e.g., current mode logic (CML), differential current switch logic (DCSL), etc.)
116		. . Schottky-gate FET (i.e., MESFET)
117		. . . Depletion or enhancement
118		. . . Diode transistor logic
119		. . MOSFET (i.e., metal-oxide semiconductor field-effect transistor)
120		. . . Depletion or enhancement
121		. . . CMOS
122		. . Complementary FET`s
123		. . With semiconductor diode or negative resistance device
124		. Bipolar transistor (e.g., RTL, DCTL, etc.)
125		. . Wired logic or open collector logic (e.g., wired-OR, wired-AND, dotted logic, etc.)
126		. . Emitter-coupled or emitter-follower logic
127		. . . Current mode logic (CML)
128		. . Transistor-transistor logic (TTL)
129		. . . Complementary transistor logic (CTL)
130		. . Diode-transistor logic (DTL)
131		. . . With metal semiconductor junction diode (e.g., Schottky barrier, etc.)
132		. . With negative resistance device (e.g., tunnel diode, thyristor, etc.)
133		. Diode
134		. . Negative resistance diode (e.g., tunnel, gunn, etc.)
135		. Negative resistance device
136		MISCELLANEOUS

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Last Modified: 6 October 2000