CN102651635A

CN102651635A - Fully differential power current amplifier

Info

Publication number: CN102651635A
Application number: CN2012101515858A
Authority: CN
Inventors: 李效龙; 张冰
Original assignee: Jiangsu University of Science and Technology
Current assignee: Jiangsu University of Science and Technology
Priority date: 2012-05-15
Filing date: 2012-05-15
Publication date: 2012-08-29
Anticipated expiration: 2032-05-15
Also published as: CN102651635B

Abstract

The invention discloses a fully differential power current amplifier, which consists of an active amplification network and a feedback network, wherein the active amplification network consists of two identical standard active two-port amplification networks, and the feedback network consists of a current parallel negative feedback network realized by two respective free transformers and a current series negative feedback network realized by two single passive devices. The standard active two-port amplification networks and the transformers form one group in a pairwise way, the dotted end of a primary coil of each transformer is connected with the reverse-phase output end of the standard active two-port amplification networks, the unlike end of the primary coil is connected with a load, the dotted end of a secondary coil of each transformer is connected with the same-phase input end of the standard active two-port amplification networks, and the unlike end of the secondary coil is grounded. Two ends of the passive devices are respectively and simultaneously connected with the same-phase output end and the reverse-phase input end of one standard active two-port amplification network in the two standard active two-port amplification networks. The fully differential power current amplifier has the advantages that the integration degree is high, the cost is low, and the performance is good.

Description

A kind of fully differential power current amplifier

Technical field

The invention belongs to the analog integrated circuit technical field, specifically relate to a kind of fully differential power current amplifier.

Background technology

Impedance matching is the Design of Broadband Amplifier difficult point.The circuit structure of common broadband (or ultra broadband) amplifier; Like common gate (or common base) amplifier, distributed amplifier and resistive voltage amplifier with parallel negative-feedback etc.; Between its impedance matching and the important parameters such as noise, the linearity and power consumption or chip area is relevant; The realization that is its impedance matching is worsening noise, or reduce the linearity, or increases power consumption or chip area etc. and exchange for for cost.Secondly, these do not have the input impedance and the transfer function of explication at amplifier in the broadband, so gain is uneven in its band.The 3rd, the output signal of these amplifiers is a power signal, so the output of amplifier also needs impedance matching network.The 4th, the input signal of these amplifiers is single-ended signal with the output signal, so the ability of its anti-interference signal, is not suitable for remote transmission signal.

A kind of fully differential power current amplifier of the present invention does not still have relevant document introduction at present, does not also search relevant patent document.

Summary of the invention

The object of the invention is the defective that exists to prior art with the technical problem that will solve, and proposes a kind of fully differential power current amplifier.

For achieving the above object, the technical scheme that the present invention adopts is:

A kind of fully differential power current amplifier is made up of active amplification network and feedback network; Said active amplification network amplifies networks 1 by active two ports of two identical the-standards to be formed with the active two ports amplification of second standard network 1, and said feedback network is made up of two identical the-transformers 2 and second transformer 2 and passive device 3; Active two ports of wherein said the-standard amplify network 1 and are connected with the power signal of input difference with the in-phase input end that active two ports of second standard amplify network 1; The end of the same name of described first transformer, 2 primary coils links to each other with the inverse output terminal that active two ports of described first standard amplify network 1, and its different name end links to each other with an end of load; The end of the same name of described first transformer, 2 secondary coils links to each other its different name end ground connection with the in-phase input end that active two ports of described first standard amplify network 1; The end of the same name of described second transformer, 2 primary coils links to each other with the inverse output terminal that active two ports of described second standard amplify network 1, and its different name end links to each other with the other end of load; The end of the same name of described second transformer, 2 secondary coils links to each other its different name end ground connection with the in-phase input end that active two ports of described second standard amplify network 1; One end of described passive device 3 connects inverting input and the in-phase output end that active two ports of described first standard amplify network 1 simultaneously, and its other end connects inverting input and the in-phase output end that active two ports of described second standard amplify network 1 simultaneously; Described the-, active two ports of second standard differential current signal of amplifying the reversed-phase output output of network 1 flows through the respectively-, export load to behind the primary coil of second transformer 2.

Above-mentioned the-, active two ports of second standard output signal that amplifies network 1 is current signal.

Above-mentioned the-, second transformer 2 constitutes two negative feedback networks that configuration is a current parallel, passive device 3 constitutes the negative feedback network that two configurations are the electric current series connection.

Above-mentioned-, second transformer 2 has high turn ratio and high magnetic coefficient simultaneously.

Above-mentioned passive device 3 can be any in resistance, inductance or the microstrip line.

A kind of fully differential power current-amplifying appliance of the present invention has following advantage and beneficial effect:

1, because the design of impedance matching, noise and distortion in a kind of fully differential power current amplifier of the present invention is a quadrature, so it can realize impedance matching, low noise and high linearity simultaneously in the broadband;

2, because a kind of fully differential power current amplifier of the present invention has the input impedance and the transfer function of explication in the broadband, so it can realize good impedance matching in the broadband, and is with interior flat gain;

3, because the output signal of a kind of differential power current amplifier of the present invention is a current signal, so its output does not need impedance matching network;

4, because the input/output signal of a kind of fully differential power current amplifier of the present invention is differential signal, so its common-mode rejection ratio is high, long transmission distance.

Description of drawings

Fig. 1 is a principle schematic of the present invention;

Fig. 2 is the practical implementation circuit diagram of Fig. 1;

Among the figure: 1. active two ports of standard amplify network, 2. transformer, 3. passive device.

Embodiment

In order to deepen to understanding of the present invention, below in conjunction with embodiment and accompanying drawing the present invention is made further detailed description, this embodiment only is used to explain the present invention, does not constitute the regulation to protection range of the present invention.

Shown in Figure 2 is a kind of practical implementation circuit diagram based on CMOS technology of Fig. 1.As depicted in figs. 1 and 2, a kind of fully differential power current amplifier is made up of active amplification network and feedback network; Wherein, said active amplification network amplifies network 1 by two active two ports of identical standard to be formed, and negative feedback network and two configurations that said feedback network is a current parallel by two configurations are that the negative feedback network that electric current is connected is formed.Described two current parallel negative feedback networks are realized by two identical transformers 2 respectively.Described two electric currents series connection negative feedback network is realized by single passive device 3.In Fig. 2, active two ports of described first standard amplify network 1 and realize that by the dual-stage amplifier that transistor VF1, VF3 and VF4 constitute wherein its input stage is made up of commonsource amplifier VF1, and its output stage is made up of fully-differential amplifier VF3 and VF4; The dual-stage amplifier with the active two ports amplification of described first standard network 1 symmetry that the active two ports amplification of described second standard network 1 is made up of transistor VF2, VF5 and VF6 is realized; Wherein its input stage is made up of commonsource amplifier VF2, and its output stage is made up of fully-differential amplifier VF5 and VF6.Transistor VF7～VF16 is that transistor VF1 ~ VF6 provides bias current.Described two transformers 2 are the integrated transformer realization of 1:N by turn ratio, indicate with TF1 and TF2 respectively.The resistance that described single passive device 3 is R/2 by two resistances is in series.For example, if getting R is 2.5 Ω, then the effective turn of transformer TF1 and TF2 is 20 than N.Power signal (the u of difference _In+, u _In-And i _In+, i _In-) input to the grid of VF1 and VF2.Couple directly to the grid of VF3 and VF5 simultaneously by the single-ended signal of the drain electrode of VF1 output, the signal of being exported by the drain electrode of VF2 then couples directly to the grid of VF4 and VF6 simultaneously.Be coupled to the source electrode of VF1 and VF2 respectively separately through capacitor C 1 and C2 by the current signal of the drain electrode of VF3 and VF6 output, the source electrode of VF1 and VF2 links to each other with an end of two resistance R/2 separately.The current signal of being exported by the drain electrode of VF4 and VF5 links to each other with the end of the same name of transformer TF2 primary coil with transformer TF1 respectively, and its different name end then is connected to load (Z through coupling capacitance C3 and C4 respectively _L) two ends.After the differential current signal of promptly being exported by the drain electrode of VF4 and VF5 flows through the primary coil and coupling capacitance C3 and C4 of transformer TF1 and transformer TF2, the output current signal (i of difference _O-, i _O+) inflow load Z _LThe end of the same name of transformer TF1 and transformer TF2 secondary coil links to each other with the grid of VF1 and VF2 respectively separately, and its different name end then all is connected to a voltage source U that direct current biasing is provided for grid _GGVF13, VF14 and resistance R among Fig. 2 ' formation combination current source.Be source electrode and the power supply U of VF13 _DDLink to each other, its drain and gate all with resistance R ' an end link to each other, and the source ground of VF14, its drain and gate all with resistance R ' the other end link to each other.VF7～VF12 is the mirror current source of VF13, and VF15 and VF16 then are the mirror current source of VF14.The grid that is VF7～VF12 all links to each other with drain electrode with the grid of VF13, its source electrode all with power supply U _DDLink to each other.The grid of VF15 and VF16 all links to each other with drain electrode with the grid of VF14, and its source electrode all is connected to ground.The drain electrode of VF7 links to each other with the drain electrode of VF1; The drain electrode of VF12 links to each other with the drain electrode of VF2; The drain electrode of VF8 links to each other with the drain electrode of VF3; The drain electrode of VF9 links to each other with the different name end of transformer TF1 primary coil, and the drain electrode of VF10 links to each other with the different name end of the primary coil of transformer TF2, and the drain electrode of VF11 links to each other with the drain electrode of VF6.The source electrode of VF3～VF6 all is connected to the drain electrode of VF16, two resistance R/2 link to each other one be connected to VF15 drain electrode.In the above-mentioned transistor, VF1～VF6 and VF14～VF16 are the N-channel mosfet, and VF7～VF13 is the P-channel mosfet.Wherein VF7 and VF12's is measure-alike, and VF8～VF11's is measure-alike, and VF1 and VF2's is measure-alike, and VF3～VF6's is measure-alike.

Present embodiment is made based on CMOS technology, and all devices all can be integrated in the same chip, so integrated level is high, and cost is low, and performance is good.

Claims

1. a fully differential power current amplifier is made up of active amplification network and feedback network; Said active amplification network amplifies network (1) by active two ports of the-standard and the active two ports amplification networks of second standard (1) are formed; It is characterized in that said feedback network is made up of the-transformer (2), second transformer (2) and passive device (3); Active two ports of wherein said the-standard amplify network (1) and are connected with the power signal of input difference with the in-phase input end that active two ports of second standard amplify network (1); The end of the same name of described first transformer (2) primary coil links to each other with the inverse output terminal that active two ports of described first standard amplify network (1), and its different name end links to each other with an end of load; The end of the same name of described first transformer (2) secondary coil links to each other its different name end ground connection with the in-phase input end that active two ports of described first standard amplify network (1); The end of the same name of described second transformer (2) primary coil links to each other with the inverse output terminal that active two ports of described second standard amplify network (1), and its different name end links to each other with the other end of load; The end of the same name of described second transformer (2) secondary coil links to each other its different name end ground connection with the in-phase input end that active two ports of described second standard amplify network (1); One end of described passive device (3) connects inverting input and the in-phase output end that active two ports of described first standard amplify network (1) simultaneously, and its other end connects inverting input and the in-phase output end that active two ports of described second standard amplify network (1) simultaneously; Described the-, active two ports of second standard differential current signal of amplifying the reversed-phase output output of networks (1) flows through the respectively-, export load to behind the primary coil of second transformer (2).

2. a kind of fully differential power current amplifier according to claim 1 is characterized in that: described the-, active two ports of second standard output signal that amplifies networks (1) is current signal.

3. a kind of fully differential power current amplifier according to claim 1; It is characterized in that: in the described feedback network the-, second transformer (2) constitutes two negative feedback networks that configuration is a current parallel, passive device (3) constitutes the negative feedback network that two configurations are the electric current series connection.

4. a kind of fully differential power current amplifier according to claim 1 is characterized in that: said-, second transformer (2) has high turn ratio and high magnetic coefficient simultaneously.

5. a kind of fully differential power current amplifier according to claim 1 is characterized in that: described passive device (3) can be any in resistance, inductance or the microstrip line.