Amplifier and electronic circuit

Patent metadata

Field	Value
Publication number	US-10587227-B2
Application number	US-201615554366-A
Country	US
Kind code	B2
Filing date	Feb 3, 2016
Priority date	Mar 24, 2015
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

An amplifier includes a P-type transistor and an N-type transistor connected in series, and an operational amplifier. An output terminal of the operational amplifier is connected to gates of both the P-type transistor and the N-type transistor. One of an inverting input terminal and a non-inverting input terminal of the operational amplifier is connected to drains of both the P-type transistor and the N-type transistor. Further, a predetermined reference voltage is applied to another of the inverting input terminal and the non-inverting input terminal.

First claim

The invention claimed is:

1. An amplifier, comprising:
a P-type transistor and an N-type transistor connected in series;
an operational amplifier, wherein
an output terminal of the operational amplifier is connected to gates of both the P-type transistor and the N-type transistor, one of an inverting input terminal and a non-inverting input terminal of the operational amplifier is connected to drains of both the P-type transistor and the N-type transistor, and a predetermined reference voltage is applied to another of the inverting input terminal and the non-inverting input terminal;
a bias voltage supply unit that supplies a predetermined bias voltage to the gate of one of the P-type transistor and the N-type transistor; and
a capacitor inserted between the gate of the P-type transistor and the gate of the N-type transistor.

2. The amplifier according to claim 1 , further comprising:
a current source connected to the drain.

3. The amplifier according to claim 2 , further comprising:
a comparator that compares a potential of the gate and a predetermined potential and supplies a result of the comparison, wherein
the current source supplies the predetermined current on a basis of the comparison result of the comparator.

4. The amplifier according to claim 2 , further comprising:
a low-pass filter, wherein
the current source includes a transistor, and
the low-pass filter supplies a DC bias voltage to a gate terminal of the transistor.

5. The amplifier according to claim 1 , further comprising:
an impedance matching circuit that causes impedances of circuits on both ends of a transmission channel connected to the amplifier to match with each other.

6. The amplifier according to claim 1 , wherein
the predetermined reference voltage is a value equal to or more than a saturation drain voltage of one of the P-type transistor and the N-type transistor.

7. An amplifier, comprising:
a P-type transistor and an N-type transistor connected in series;
an operational amplifier, wherein
an output terminal of the operational amplifier is connected to gates of both the P-type transistor and the N-type transistor, one of an inverting input terminal and a non-inverting input terminal of the operational amplifier is connected to drains of both the P-type transistor and the N-type transistor, and a predetermined reference voltage is applied to another of the inverting input terminal and the non-inverting input terminal;
a current source connected to the drain; and
a cascode transistor device inserted between the drain and the current source.

8. An electronic circuit, comprising:
an amplifier including a P-type transistor and an N-type transistor connected in series and an operational amplifier, in which an output terminal of the operational amplifier is connected to gates of both the P-type transistor and the N-type transistor, one of an inverting input terminal and a non-inverting input terminal of the operational amplifier is connected to drains of both the P-type transistor and the N-type transistor, and a predetermined reference voltage is applied to another of the inverting input terminal and the non-inverting input terminal;
a signal processing unit that processes a signal output from the drain;
a bias voltage supply unit that supplies a bias voltage having a value indicated by a control signal to the gate of one of the P-type transistor and the N-type transistor; and
a capacitor inserted between the gate of the P-type transistor and the gate of the N-type transistor.

9. The electronic circuit according to claim 8 , wherein
the signal processing unit processes a signal output from the drain and generates the control signal on a basis of a level of the signal.

Assignees

• Sony Corp

Inventors

• Takano Hideyuki
• Kondo Fumitaka
• Shoji Norio

Classifications

• H03F3/189

  High-frequency amplifiers, e.g. radio frequency amplifiers · CPC title

• H03F2200/294

  the amplifier being a low noise amplifier [LNA] · CPC title

• H03F1/26 Primary

  Modifications of amplifiers to reduce influence of noise generated by amplifying elements · CPC title

• H03F3/193

  with field-effect devices (H03F3/195 takes precedence) · CPC title

• H03F2200/372

  Noise reduction and elimination in amplifier · CPC title