US 7,239,209 B2Granted

Serially RC coupled quadrature oscillator

AssigneeSharp Kabushiki Kaisha

InventorAlberto O. Adan

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Abstract

The oscillator includes: a first oscillator circuit in which first and second transistors cross-connected to each other are connected to a resonant circuit; and a second oscillator circuit in which third and fourth transistors cross-connected to each other are connected to a resonant circuit, wherein a coupling capacitor and coupling resistor are serially provided between a collector terminal of the first transistor and a base terminal of the fourth transistor, and a coupling capacitor and coupling resistor are serially provided between a collector terminal of the second transistor and a base terminal of the third transistor, and a coupling capacitor and coupling resistor are serially provided between a collector terminal of the third transistor and a base terminal of the first transistor, and a coupling capacitor and coupling resistor are serially provided between a collector terminal of the fourth transistor and a base terminal of the second transistor. On this account, it is possible to suppress noises and reduce power consumption.

Claims13

Dependent claims

An oscillator, comprising:

a first oscillator circuit which has a resonant circuit and a plurality of transistors;
and a second oscillator circuit which has a resonant circuit and a plurality of transistors, wherein:
the first oscillator circuit is provided with first and second transistors so that a first conductive terminal of the first transistor is connected to a first conductive terminal of the second transistor and a second conductive terminal of the first transistor and a second conductive terminal of the second transistor are respectively connected to the resonant circuit, and the second conductive terminal of the first transistor is connected to a control terminal of the second transistor directly or via a capacitor, and a control terminal of the first transistor is connected to the second conductive terminal of the second transistor directly or via a capacitor, and
the second oscillator circuit is provided with third and fourth transistors so that a first conductive terminal of the third transistor is connected to a first conductive terminal of the fourth transistor and a second conductive terminal of the third transistor and a second conductive terminal of the fourth transistor are respectively connected to the resonant circuit, and the second conductive terminal of the third transistor is connected to a control terminal of the fourth transistor directly or via a capacitor, and a control terminal of the third transistor is connected to the second conductive terminal of the fourth transistor directly or via a capacitor, and
a coupling capacitor and a coupling resistor are serially provided between the second conductive terminal of the first transistor and the control terminal of the fourth transistor, and
a coupling capacitor and a coupling resistor are serially provided between the second conductive terminal of the second transistor and the control terminal of the third transistor, and
a coupling capacitor and a coupling resistor are serially provided between the second conductive terminal of the third transistor and the control terminal of the first transistor, and
a coupling capacitor and a coupling resistor are serially provided between the second conductive terminal of the fourth transistor and the control terminal of the second transistor.

5 more elements

An oscillator, comprising:

a first oscillator circuit which has a resonant circuit and a plurality of transistors;
and a second oscillator circuit which has a resonant circuit and a plurality of transistors, wherein:
the first oscillator circuit is provided with (i) first and second MOS transistors so that a first conductive terminal of the first MOS transistor is connected to a first conductive terminal of the second MOS transistor and a second conductive terminal of the first MOS transistor is connected to a second conductive terminal of the second MOS transistor and (ii) third and fourth MOS transistors so that a first conductive terminal of the third MOS transistor is connected to a first conductive terminal of the fourth MOS transistor and a second conductive terminal of the third MOS transistor is connected to a second conductive terminal of the fourth MOS transistor, and the first conductive terminal of the second MOS transistor is connected to the first conductive terminal of the third MOS transistor, and the second conductive terminal of the second MOS transistor and the second conductive terminal of the third MOS transistor are respectively connected to the resonant circuit, and the second conductive terminal of the second MOS transistor is connected to a control terminal of the third MOS transistor, and a control terminal of the second MOS transistor is connected to the second conductive terminal of the third MOS transistor, and
the second oscillator circuit is provided with (i) fifth and sixth MOS transistors so that a first conductive terminal of the fifth MOS transistor is connected to a first conductive terminal of the sixth MOS transistor and a second conductive terminal of the fifth MOS transistor is connected to a second conductive terminal of the sixth MOS transistor and (ii) seventh and eighth MOS transistors so that a first conductive terminal of the seventh MOS transistor is connected to a first conductive terminal of the eighth MOS transistor and a second conductive terminal of the seventh MOS transistor is connected to a second conductive terminal of the eighth MOS transistor, and the first conductive terminal of the sixth MOS transistor is connected to the first conductive terminal of the seventh MOS transistor, and the second conductive terminal of the sixth MOS transistor and the second conductive terminal of the seventh MOS transistor are respectively connected to the resonant circuit, and the second conductive terminal of the sixth MOS transistor is connected to a control terminal of the seventh MOS transistor, and a control terminal of the sixth MOS transistor is connected to the second conductive terminal of the seventh MOS transistor, and
a coupling capacitor and a coupling resistor are serially provided between (a) the second conductive terminals of the fifth and sixth MOS transistors and (b) the control terminal of the first MOS transistor, and
a coupling capacitor and a coupling resistor are serially provided between (c) the second conductive terminals of the seventh and eighth MOS transistors and (d) the control terminal of the fourth MOS transistor, and
a coupling capacitor and a coupling resistor are serially provided between (e) the second conductive terminals of the third and fourth MOS transistors and (f) the control terminal of the fifth MOS transistor, and
a coupling capacitor and a coupling resistor are serially provided between (g) the second conductive terminals of the first and second MOS transistors and (h) the control terminal of the eighth MOS transistor.

5 more elements

A communication device, comprising an oscillator which includes:

a first oscillator circuit which has a resonant circuit and a plurality of transistors;
and a second oscillator circuit which has a resonant circuit and a plurality of transistors, wherein:
the first oscillator circuit is provided with first and second transistors so that a first conductive terminal of the first transistor is connected to a first conductive terminal of the second transistor and a second conductive terminal of the first transistor and a second conductive terminal of the second transistor are respectively connected to the resonant circuit, and the second conductive terminal of the first transistor is connected to a control terminal of the second transistor directly or via a capacitor, and a control terminal of the first transistor is connected to the second conductive terminal of the second transistor directly or via a capacitor, and
the second oscillator circuit is provided with third and fourth transistors so that a first conductive terminal of the third transistor is connected to a first conductive terminal of the fourth transistor and a second conductive terminal of the third transistor and a second conductive terminal of the fourth transistor are respectively connected to the resonant circuit, and the second conductive terminal of the third transistor is connected to a control terminal of the fourth transistor directly or via a capacitor, and a control terminal of the third transistor is connected to the second conductive terminal of the fourth transistor directly or via a capacitor, and
a coupling capacitor and a coupling resistor are serially provided between the second conductive terminal of the first transistor and the control terminal of the fourth transistor, and
a coupling capacitor and a coupling resistor are serially provided between the second conductive terminal of the second transistor and the control terminal of the third transistor, and
a coupling capacitor and a coupling resistor are serially provided between the second conductive terminal of the third transistor and the control terminal of the first transistor, and
a coupling capacitor and a coupling resistor are serially provided between the second conductive terminal of the fourth transistor and the control terminal of the second transistor.

5 more elements

A communication device, comprising an oscillator which includes:

a first oscillator circuit which has a resonant circuit and a plurality of transistors;
and a second oscillator circuit which has a resonant circuit and a plurality of transistors, wherein:
the first oscillator circuit is provided with (i) first and second MOS transistors so that a first conductive terminal of the first MOS transistor is connected to a first conductive terminal of the second MOS transistor and a second conductive terminal of the first MOS transistor is connected to a second conductive terminal of the second MOS transistor and (ii) third and fourth MOS transistors so that a first conductive terminal of the third MOS transistor is connected to a first conductive terminal of the fourth MOS transistor and a second conductive terminal of the third MOS transistor is connected to a second conductive terminal of the fourth MOS transistor, and the first conductive terminal of the second MOS transistor is connected to the first conductive terminal of the third MOS transistor, and the second conductive terminal of the second MOS transistor and the second conductive terminal of the third MOS transistor are respectively connected to the resonant circuit, and the second conductive terminal of the second MOS transistor is connected to a control terminal of the third MOS transistor, and a control terminal of the second MOS transistor is connected to the second conductive terminal of the third MOS transistor, and
the second oscillator circuit is provided with (i) fifth and sixth MOS transistors so that a first conductive terminal of the fifth MOS transistor is connected to a first conductive terminal of the sixth MOS transistor and a second conductive terminal of the fifth MOS transistor is connected to a second conductive terminal of the sixth MOS transistor and (ii) seventh and eighth MOS transistors so that a first conductive terminal of the seventh MOS transistor is connected to a first conductive terminal of the eighth MOS transistor and a second conductive terminal of the seventh MOS transistor is connected to a second conductive terminal of the eighth MOS transistor, and the first conductive terminal of the sixth MOS transistor is connected to the first conductive terminal of the seventh MOS transistor, and the second conductive terminal of the sixth MOS transistor and the second conductive terminal of the seventh MOS transistor are respectively connected to the resonant circuit, and the second conductive terminal of the sixth MOS transistor is connected to a control terminal of the seventh MOS transistor, and a control terminal of the sixth MOS transistor is connected to the second conductive terminal of the seventh MOS transistor, and
a coupling capacitor and a coupling resistor are serially provided between (a) the second conductive terminals of the fifth and sixth MOS transistors and (b) the control terminal of the first MOS transistor, and
a coupling capacitor and a coupling resistor are serially provided between (c) the second conductive terminals of the seventh and eighth MOS transistors and (d) the control terminal of the fourth MOS transistor, and
a coupling capacitor and a coupling resistor are serially provided between (e) the second conductive terminals of the third and fourth MOS transistors and (f) the control terminal of the fifth MOS transistor, and
a coupling capacitor and a coupling resistor are serially provided between (g) the second conductive terminals of the first and second MOS transistors and (h) the control terminal of the eighth MOS transistor.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/253,732Filed 20 Oct 2005
Priority: JP 2004-30720321 Oct 2004
Published: US 2006/0097801 A111 May 2006
Granted: 3 Jul 2007
Term ends: Not estimatedThe source records don’t support an estimate.

Classification7 codes

H03B 27/00
Generation of oscillations providing a plurality of outputs of the same frequency
H03B 5/1215
The amplifier comprising a pair of transistors, wherein an output terminal of each being connected to an input terminal of the other, e.g. a…
H03B 5/1231
Active element in amplifier being semiconductor device: the amplifier comprising one or more bipolar transistors
H03B 5/1243
The means comprising a voltage dependent capacitance: the means comprising voltage variable capacitance diodes