EP0131337A1
Expired / Lapsed
EP
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Double-balanced mixer circuit
Assignee: Koninklijke Philips NV
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Filing: 1984-07-05
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Granted: —
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Expires: 2004-07-05
Abstract
Abstract Two cross-coupled differential amplifiers (T 1 . T 2 and T 3 , T.) have a common first (1) and a common second (2) base terminal to which an oscillator signal is applied. Via transformer (12) the radio-frequency signal from a source (10) having an impedance (11) is applied to a balanced common-base circuit comprising the transistors (T., T 6 ), whose collectors are coupled to the common-emitter terminals (3) and (4) of the differential amplifiers (T 1 , T 2 ; T 3 , T 4 ) respectively. With such a mixer circuit a better intermodulation and noise behaviour is obtained when compared with the usual differential amplifier instead of the balanced common-base circuit.
Inventors
- 👤 Abraham Jongepier
- 👤 Wolfdietrich Georg Kasperkovitz
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 06:41
CPC Classifications
H; H03; H03D; H03D7/00; H03D7/14; H03D7/1425; H03D7/1433; H03D7/1441; H03D7/1458; H03D7/1491
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
176 words
A double-balanced mixer circuit comprising a first differential pair of first and second transistors whose emitters are connected to a common first emitter terminal, a second differential pair of third and fourth transistors whose emitters are connected to a common second emitter terminal, the bases of the first and the fourth transistor and the bases of the second and the third transistor being coupled to a common first and a common second base terminal respectively, between which base terminals a mixing signal may be applied, and a voltage-current converter having an input for receiving an input signal and having first and second outputs which are coupled to the first and the second emitter terminal respectively, characterized in that the voltage-current converter comprises a balanced, common-base circuit comprising a fifth and a sixth transistor, whose bases are earthed for signal current, whose collectors are coupled to the first and the second emitter terminal respectively and whose emitters are coupled to a common power-supply terminal via respective current-supply elements, which emitters constitute the input of the voltage-current converter.
Claim 2
Dependent Claim
176 words
A double-balanced mixer circuit comprising a first differential pair of first and second transistors whose emitters are connected to a common first emitter terminal, a second differential pair of third and fourth transistors whose emitters are connected to a common second emitter terminal, the bases of the first and the fourth transistor and the bases of the second and the third transistor being coupled to a common first and a common second base terminal respectively, between which base terminals a mixing signal may be applied, and a voltage-current converter having an input for receiving an input signal and having first and second outputs which are coupled to the first and the second emitter terminal respectively, characterized in that the voltage-current converter comprises a balanced, common-base circuit comprising a fifth and a sixth transistor, whose bases are earthed for signal current, whose collectors are coupled to the first and the second emitter terminal respectively and whose emitters are coupled to a common power-supply terminal via respective current-supply elements, which emitters constitute the input of the voltage-current converter.
Claim 3
Dependent Claim
71 words
A double-balanced mixer circuit as claimed in Claim 1, characterized in that the input signal is applied to one terminal of the primary of a transformer, the other primary terminal being coupled to a terminal which is at a fixed voltage, which transformer has first and second secondary windings which have a common terminal and whose other terminals are coupled to the emitters of the fifth and the sixth transistor respectively.
Claim 4
Dependent Claim
56 words
A modification of a circuit as claimed in Claim 1 or 2 in which the emitters, collectors and bases are replaced by sources, drains and gates respectively, the emitter terminals are replaced by source terminals, the base terminals are replaced by gate terminals and the balanced common-base circuit is replaced by a balanced common gate circuit.
References Cited (Backward Citations)
DE2929918A1
Cited
GB2089156A
Cited
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