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US6046486A Expired / Lapsed US ⏱️ 0.0 years remaining

Heterojunction bipoplar mixer circuitry

Assignee: Fairchild Semiconductor Corp
•
Filing: 1998-08-21
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Granted: 2000-04-04
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Expires: 2018-08-21
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Abstract

Abstract Mixer circuitry having a semiconductor body formed therein mixer circuitry having an oscillator having a heterojunction bipolar transistor and a mixer having a Schottky diode. The heterojunction transistor has a collector region formed in one portion of doped layer of the semiconductor body and the diode has a metal electrode is Schottky contact with another portion of such doped layer. The mixer is includes a diode and a DC biasing circuit, comprising a constant current, for biasing such diode to predetermined operating point substantially invariant with power of an input signal fed to such mixer.

Inventors

  • 👤 Brian J. McNamara
  • 👤 John P. Wendler
  • 👤 Kamal Tabatabaje-Alavi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 19:54
CPC Classifications
H; H03; H03D; H03D7/00; H03D7/02; H10; H10D; H10D84/00; H10D84/01; H10D84/02; H10D84/05

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 100 words
Mixer circuitry comprising: a semiconductor body, such body having formed therein circuitry comprising: an oscillator having a heterojunction bipolar transistor and adapted to provide an output signal; and, a mixer having a Schottky diode coupled to receive the output signal, the heterojunction transistor having a collector region formed in one portion of a doped layer of the semiconductor body and the diode having a metal electrode in Schottky contact with another portion of such doped layer; and a bias circuit adapted to DC bias the Schottky diode to a predetermined operating condition substantially invariant with power of the output signal.
Claim 2
Dependent Claim 100 words
Mixer circuitry comprising: a semiconductor body, such body having formed therein circuitry comprising: an oscillator having a heterojunction bipolar transistor and adapted to provide an output signal; and, a mixer having a Schottky diode coupled to receive the output signal, the heterojunction transistor having a collector region formed in one portion of a doped layer of the semiconductor body and the diode having a metal electrode in Schottky contact with another portion of such doped layer; and a bias circuit adapted to DC bias the Schottky diode to a predetermined operating condition substantially invariant with power of the output signal.
Claim 3
Dependent Claim 98 words
The mixer circuitry recited in claim 1 wherein the body includes: a semi-insulating III-IV substrate; a subcollector layer disposed on the substrate; wherein the doped layer is an N type conductivity gallium arsenide collector layer disposed on the subcollector layer; a base layer disposed on the collector layer; and wherein, in one region of the body the transistor has the emitter layer thereof disposed on the base layer; and wherein, in another region of the body the Schottky diode has a cathode in contact with the subcollector layer and an anode in Schottky contact with the collector layer.
Claim 4
Dependent Claim 33 words
The mixer circuitry recited in claim 2 wherein the collector layer has a doping level in the range of 2×10 16 atoms per cm 2 to 5×10 16 atoms per cm 2 .
Claim 5
Dependent Claim 17 words
The mixer circuitry recited in claim 2 wherein the collector layer has a thickness of 0.5 micrometers.
Claim 6
Dependent Claim 13 words
The mixer circuitry recited in claim 4 wherein the substrate is gallium arsenide.
Claim 7
Dependent Claim 17 words
The mixer circuitry recited in claim 5 wherein the subcollector layer is N+ type conductivity gallium arsenide.
Claim 8
Dependent Claim 17 words
The mixer circuitry recited in claim 6 wherein the base layer is P+ type conductivity gallium arsenide.
Claim 9
Dependent Claim 19 words
The mixer circuitry recited in claim 7 wherein the emitter layer is indium gallium phosphide or aluminum gallium arsenide.
Claim 10
Dependent Claim 19 words
The mixer circuitry recited in claim 1 wherein the bias circuit provides a constant current to the Schottky diode.
Claim 11
Dependent Claim 23 words
The mixer circuitry recited in claim 9 wherein the predetermined operating condition is one of substantially minimum conversion loss of the Schottky diode.
Claim 12
Dependent Claim 40 words
Mixer circuitry comprising: a semiconductor body having a Schottky diode formed therein; and a bias circuit adapted to DC bias the Schottky diode to a predetermined operating condition substantially invariant with power of a signal received by the Schottky diode.
Claim 13
Dependent Claim 40 words
Mixer circuitry comprising: a semiconductor body having a Schottky diode formed therein; and a bias circuit adapted to DC bias the Schottky diode to a predetermined operating condition substantially invariant with power of a signal received by the Schottky diode.
Claim 14
Dependent Claim 19 words
The mixer circuitry recited in claim 1 wherein the bias circuit provides a constant current to the Schottky diode.
Claim 15
Dependent Claim 23 words
The mixer circuitry recited in claim 12 wherein the predetermined operating condition is one of substantially minimum conversion loss of the Schottky diode.
Claim 16
Dependent Claim 31 words
The mixer circuitry recited in claim 13 wherein the semiconductor body also has an oscillator, including a heterojunction bipolar transistor, formed therein that provides the signal received by the Schottky diode.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-04-04 2003-10-04 2004-04-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-04-04 2007-10-04 2008-04-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-04-04 2011-10-04 2012-04-04 $7700.00 Window Closed / Lapsed

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