Phase shift amplifier and its applications to a recombining circuit

• US 5,877,643 A
• Filed: 08/19/1997
• Issued: 03/02/1999
• Est. Priority Date: 12/22/1993
• Status: Expired due to Fees

• Current Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Drogi, Serge
• Primary Examiner(s): Wells, Kenneth B.
• Application Number:
  US08/916,748
• Time in Patent Office: 560 Days
• Field of Search: 327/231, 327/232, 327/233, 327/234, 327/238, 327/240, 327/242, 327/245, 327/250, 327/254, 327/256, 327/260, 327/252, 327/258, 327/355, 327/356, 327/357, 327/359, 330/261, 330/294, 330/252, 330/109, 330/110
• US Class Current: 327/256
• CPC Class Codes: H03H 11/22 providing two or more phase shifted output signals, e.g. n-phase output

Abstract

Phase shift amplifier formed by a differential pair of input transistors each collector of which transistors is connected to a respective phase shift resistor and to a phase shift capacitor, whereas the other ends of each phase shift resistor form nodes A and B respectively, while the other ends of the phase shift capacitors are connected in a cross-coupling. According to the invention, the nodes A and B are connected to the input of amplifiers of the transimpedance type at the output of which amplifiers a differential signal is available which is phase shifted relative to the differential input signal.

Claims

1. A recombining circuit which includes a first and a second phase-shift amplifier which are configured to receive respective differential input signals which are phase shifted relative to each other, wherein each of the phase-shift amplifiers includes:

a differential pair of a first and a second transistor, a steady current source, transimpedance amplifier means for transforming a differential current into a differential voltage, a first and a second phase-shift resistor, a first and a second phase-shift capacitor, a first and a second load impedance, and a first and a second supply terminal,

the steady current source being coupled between the first supply terminal and respective first main electrodes of the first and second resistor,

the first and second phase-shift resistors being coupled between respective second main electrodes of the first and second transistors and a first and a second input terminal of the transimpedance amplifier means, respectively,

the first phase-shift capacitor being coupled between the second main electrode of the first transistor and the second input terminal of the transimpedance amplifier means, and the second phase-shift capacitor being coupled between the second main electrode of the second transistor and the first input terminal of the transimpedance amplifier means, and

the first and second load impedances being coupled between the second supply terminal and a first and a second output terminal of the transimpedance amplifier, respectively,

wherein the differential current is produced at the first and second input terminals of transimpedance amplifier means, the differential current being phase-shifted relative to a differential input signal to be applied to respective control terminals of the first and second transistors, and

wherein the differential voltage is an output voltage of the phase-shift amplifier,

the recombining circuit further including a summation node at which the output voltages produced by the first and second phase-shift amplifiers are summed, to thereby produce a high impedance output voltage.

2. A transceiver station which includes a recombining circuit including a first and a second phase-shift amplifier which are configured to receive respective differential input signals which are phase shifted relative to each other, wherein each of the phase-shift amplifiers includes:

a differential pair of a first and a second transistor, a steady current source, transimpedance amplifier means for transforming a differential current into a differential voltage, a first and a second phase-shift resistor, a first and a second phase-shift capacitor, a first and a second load impedance, and a first and a second supply terminal,

the steady current source being coupled between the first supply terminal and respective first main electrodes of the first and second resistor,

the first and second phase-shift resistors being coupled between respective second main electrodes of the first and second transistors and a first and a second input terminal of the transimpedance amplifier means, respectively,

the first phase-shift capacitor being coupled between the second main electrode of the first transistor and the second input terminal of the transimpedance amplifier means, and the second phase-shift capacitor being coupled between the second main electrode of the second transistor and the first input terminal of the transimpedance amplifier means, and

the first and second load impedances being coupled between the second supply terminal and a first and a second output terminal of the transimpedance amplifier, respectively,

wherein the differential current is produced at the first and second input terminals of the transimpedance amplifier means, the differential current being phase-shifted relative to a differential input signal to be applied to respective control terminals of the first and second transistors, and

wherein the differential voltage is an output voltage of the phase-shift amplifier,

the recombining circuit further including a summation node at which the output voltages produced by the first and second phase-shift amplifiers are summed, to thereby produce a high impedance output;

voltage.

3. A phase-shift amplifier, including:

a differential pair of a first and a second transistor, a steady current source, transimpedance amplifier means for transforming a differential current into a differential voltage, a first and a second phase-shift resistor, a first and a second phase-shift capacitor, a first and a second load impedance, and a first and a second supply terminal,

the steady current source being coupled between the first supply terminal and respective first main electrodes of the first and second resistor,

the first and second phase-shift resistors being coupled between respective second main electrodes of the first and second transistors and a first and a second input terminal of the transimpedance amplifier means, respectively,

the first phase-shift capacitor being coupled between the second main electrode of the first transistor and the second input terminal of the transimpedance amplifier means, and the second phase-shift capacitor being coupled between the second main electrode of the second transistor and the first input terminal of the transimpedance amplifier means, and

the first and second load impedances being coupled between the second supply terminal and a first and a second output terminal of the transimpedance amplifier, respectively,

wherein the differential current is produced at the first and second input terminals of the transimpedance amplifier means, the differential current being phase-shifted relative to a differential input signal to be applied to respective control terminals of the first and second transistors, and

wherein the differential voltage is an output voltage of the phase-shift amplifier.