阅读说明：本技术 一种薄膜晶体管集成的放大器 (Thin film transistor integrated amplifier ) 是由 张盛东 廖聪维 梁键 安军军 邱赫梓 彭志超 杨激文 于 2020-08-17 设计创作，主要内容包括：本发明公开了一种薄膜晶体管集成的放大器,包括单端放大电路单元,其中输入放大电路用于输入放大电路用于对其信号输入端接收的信号进行放大；自举上拉电路用于对信号输出端所输出信号的电位进行上拉,并增大自举上拉电路的输出阻抗,以提升单端放大电路单元的放大增益；本发明还包括双端放大电路单元,其中正/负相输入电路用于对其正/负相信号输入端接收的正/负相位信号进行放大；正/负相位自举上拉电路用于对正/负相位输出信号的电位进行上拉,并增大正/负相位自举上拉电路的输出阻抗,以提升双端放大电路单元的放大增益；本发明通过提升单端放大电路单元、双端放大电路单元的放大增益,使得薄膜晶体管集成的放大器具有较优的性能。(The invention discloses a thin film transistor integrated amplifier, which comprises a single-ended amplifying circuit unit, wherein an input amplifying circuit is used for amplifying a signal received by a signal input end of the input amplifying circuit; the bootstrap pull-up circuit is used for pulling up the potential of a signal output by the signal output end and increasing the output impedance of the bootstrap pull-up circuit so as to improve the amplification gain of the single-ended amplification circuit unit; the invention also comprises a double-end amplifying circuit unit, wherein the positive/negative phase input circuit is used for amplifying the positive/negative phase signal received by the positive/negative phase signal input end; the positive/negative phase bootstrap pull-up circuit is used for pulling up the potential of the positive/negative phase output signal and increasing the output impedance of the positive/negative phase bootstrap pull-up circuit so as to improve the amplification gain of the double-end amplification circuit unit; the invention improves the amplification gain of the single-end amplification circuit unit and the double-end amplification circuit unit, so that the amplifier integrated by the thin film transistor has better performance.)

1. A thin film transistor integrated amplifier comprising a single-ended amplification circuit, the single-ended amplification circuit unit comprising: an input amplification circuit and a bootstrap pull-up circuit;

the input amplifying circuit is used for converting a signal received by a signal input end (VIN) of the input amplifying circuit and outputting the converted signal through a signal output end (Vout);

the bootstrap pull-up circuit is configured to pull up a potential of a signal output by a signal output terminal (Vout), and increase an output impedance of the bootstrap pull-up circuit, so as to stabilize a static operating point of the single-ended amplification circuit unit and increase an amplification gain of the single-ended amplification circuit unit, where the amplification gain of the single-ended amplification circuit unit is positively correlated to the output impedance of the bootstrap pull-up circuit.

2. The amplifier of claim 1, wherein the input amplification circuit comprises a first transistor (T1), a control electrode of the first transistor (T1) being coupled to the signal input terminal (VIN), a first electrode of the first transistor (T1) being coupled to the signal output terminal (Vout), a second electrode of the first transistor (T1) being coupled to a preset low level voltage source (VSS).

3. The amplifier of claim 1, wherein the bootstrapped pull-up circuit includes a second transistor (T2), a third transistor (T3);

a control electrode, a first electrode and a first electrode of the third transistor (T3) and the second transistor (T2) are all coupled to a preset high level voltage source (VDD), a second electrode of the third transistor (T3) is coupled to a control electrode of the second transistor (T2), and a second electrode of the second transistor (T2) is coupled to a signal output terminal (Vout);

alternatively, the bootstrapped pull-up circuit includes a second transistor (T2), a third transistor (T3), and a first pull-up capacitor (CB 1);

the control electrode and the first electrode of the third transistor (T3) and the first electrode of the second transistor (T2) are all coupled to a preset high-level voltage source (VDD), the second electrode of the third transistor (T3) is coupled to the control electrode of the second transistor (T2) and one end of a first pull-up capacitor (CB1), and the other end of the first pull-up capacitor (CB1) and the second electrode of the second transistor (T2) are coupled to a signal output end (Vout).

4. The amplifier according to any one of claims 1 to 3, wherein the amplifier further comprises a plurality of cascaded single-ended amplification circuit units, wherein the signal input terminal (VIN) of the single-ended amplification circuit unit of the first stage is configured to receive an external signal, and the signal input terminals (VIN) of the single-ended amplification circuit units of the other stages are configured to receive a signal output from the signal output terminal (Vout) of the single-ended amplification circuit unit of the previous stage;

or, the amplifier further includes a plurality of cascaded single-ended amplifying circuit units and a first inter-stage signal transmission circuit, where a signal input terminal (VIN) of the single-ended amplifying circuit unit of the first stage is configured to receive an external signal, and signal input terminals (VIN) of the single-ended amplifying circuit units of other stages are configured to receive a signal output by a signal output terminal (Vout) of the single-ended amplifying circuit unit of the previous stage;

the first inter-stage signal transmission circuit is connected between the single-ended amplification circuit units of two adjacent stages, and is used for blocking a direct current signal in an output signal of the single-ended amplification circuit unit of the previous stage and outputting an alternating current signal in the output signal to the single-ended amplification circuit unit of the next stage;

the first inter-stage signal transmission circuit is also used for providing preset direct current bias voltage for the single-ended amplification circuit unit of the next stage.

5. The amplifier of claim 4, wherein the first inter-stage signaling circuit includes a coupling capacitor (Ccp), a seventh transistor (T7), and an eighth transistor (T8);

a control electrode and a first electrode of the seventh transistor (T7) are both coupled to a preset bias voltage source (VBIAS), a second electrode of the seventh transistor (T7) is coupled to a first electrode and a control electrode of the eighth transistor (T8), a second electrode of the eighth transistor (T8) is coupled to a preset low level voltage source (VSS), and a dc bias voltage point is formed between the second electrode of the seventh transistor (T7) and the first electrode of the eighth transistor (T8) and is used for providing a preset dc bias voltage for the single-ended amplifying circuit unit of the next stage;

one end of the coupling capacitor (Ccp) is coupled to a signal output end (Vout) of the single-ended amplification circuit unit of the previous stage, the other end of the coupling capacitor (Ccp) is coupled to a dc bias voltage point, and the coupling capacitor (Vout) is configured to block a dc signal in an output signal of the single-ended amplification circuit unit of the previous stage, output an ac signal in the output signal to the dc bias voltage point, couple a preset dc bias voltage with the dc bias voltage, and input the ac signal into the single-ended amplification circuit unit of the next stage.

6. A thin film transistor integrated amplifier comprising a two-terminal amplification circuit unit, the two-terminal amplification circuit unit comprising: the positive-phase input circuit, the negative-phase input circuit, the positive-phase bootstrap pull-up circuit and the negative-phase bootstrap pull-up circuit;

the positive phase input circuit is used for converting a positive phase signal received by a positive phase signal input end (VIN _ P) and outputting the positive phase signal through a positive phase signal output end (VOUT _ P);

the negative phase input circuit is used for converting a negative phase signal received by a negative phase signal input end (VIN _ N) and outputting the negative phase signal through a negative phase signal output end (VOUT _ N);

the positive-phase bootstrap pull-up circuit is used for pulling up the potential of a positive-phase output signal output by a positive-phase signal output end (VOUT _ P) and increasing the output impedance of the positive-phase bootstrap pull-up circuit so as to stabilize the static working point of the double-end amplification circuit unit and improve the amplification gain of the double-end amplification circuit unit;

the negative phase bootstrap pull-up circuit is used for pulling up the potential of a negative phase output signal output by a negative phase signal output end (VOUT _ N) and increasing the output impedance of the negative phase bootstrap pull-up circuit so as to stabilize the static working point of the double-end amplification circuit unit and improve the amplification gain of the double-end amplification circuit unit.

7. The amplifier of claim 6, wherein the positive phase signal output terminal (VOUT _ P) is further coupled to a feedback terminal of the negative phase input circuit to form a first positive feedback loop for increasing transconductance of the negative phase input circuit to increase amplification gain of the two-terminal amplification circuit unit;

the negative phase signal output end (VOUT _ N) is further coupled to a feedback end of the positive phase input circuit to form a second positive feedback loop, and the second positive feedback loop is used for increasing transconductance of the positive phase input circuit so as to improve amplification gain of the double-end amplification circuit unit.

8. The amplifier of claim 7, wherein the negative phase input circuit includes a ninth transistor (T9), a tenth transistor (T10), and an eleventh transistor (T11);

the control electrodes of the ninth transistor (T9) and the tenth transistor (T10) are coupled to the negative phase signal input terminal (VIN _ N), the first electrode of the ninth transistor (T9) is coupled to the feedback terminal of the negative phase input circuit for receiving the positive phase output signal, the second electrode of the ninth transistor (T9) is coupled to the first electrode of the tenth transistor (T10) and forms a series intermediate node, the second electrode of the tenth transistor (T10) is coupled to a preset current source (IBIAS), the first electrode of the eleventh transistor (T11) is coupled to the series intermediate node, the second electrode of the eleventh transistor (T11) is coupled to the preset current source (IBIAS), the control electrode of the eleventh transistor (T11) is coupled to the negative phase signal output terminal (VOUT _ N), and the negative phase signal output terminal (VOUT _ N) is coupled to the feedback terminal of the positive phase input circuit;

the non-inverting input circuit includes a twelfth transistor (T12), a thirteenth transistor (T13), and a fourteenth transistor (T14);

the twelfth transistor (T12) and the thirteenth transistor (T13) have control electrodes coupled to the positive phase signal input terminal (VIN _ P), a first electrode of the twelfth transistor (T12) is coupled to the feedback terminal of the positive phase input circuit for receiving the negative phase output signal, a second electrode of the twelfth transistor (T12) is coupled to the first electrode of the thirteenth transistor (T13) and forms a series intermediate node, a second electrode of the thirteenth transistor (T13) is coupled to the preset current source (IBIAS), a first electrode of the fourteenth transistor (T14) is coupled to the series intermediate node, a second electrode of the fourteenth transistor (T14) is coupled to the preset current source (IBIAS), a control electrode of the fourteenth transistor (T14) is coupled to the positive phase signal output terminal (VOUT _ P), and the positive phase signal output terminal (VOUT _ P) is coupled to the feedback terminal of the negative phase input circuit.

9. The amplifier of claim 6, wherein the negative phase bootstrap pull-up circuit comprises: a fifteenth transistor (T15) and a sixteenth transistor (T16), a control electrode, a first electrode of the fifteenth transistor (T15), and a first electrode of the sixteenth transistor (T16) are all coupled to the preset high level voltage source (VDD), a second electrode of the fifteenth transistor (T15) is coupled to a control electrode of the sixteenth transistor (T16), and a second electrode of the sixteenth transistor (T16) is coupled to the feedback terminal of the negative phase input circuit;

alternatively, the negative phase bootstrap pull-up circuit includes: a fifteenth transistor (T15), a sixteenth transistor (T16) and a second capacitor (CB2), wherein a control electrode and a first electrode of the fifteenth transistor (T15) and a first electrode of the sixteenth transistor (T16) are all coupled to the preset high level voltage source (VDD), a second electrode of the fifteenth transistor (T15) is coupled to a control electrode of the sixteenth transistor (T16), one end of a second pull-up capacitor (CB2), and the other end of the second pull-up capacitor (CB2) and the second electrode of the sixteenth transistor (T16) are coupled to the feedback end of the negative phase input circuit.

10. The amplifier of claim 6, further comprising a plurality of cascaded two-terminal amplifying circuit units, wherein the positive phase signal input terminal (VIN _ P) and the negative phase signal input terminal (VIN _ P) of the two-terminal amplifying circuit unit of the first stage are configured to receive external positive phase signals and negative phase signals, respectively, and the positive phase signal input terminal (VIN _ P) and the negative phase signal input terminal (VIN _ P) of the two-terminal amplifying circuit unit of the other stage are configured to receive signals output from the positive phase signal output terminal (VOUT _ P) and the negative phase signal output terminal (VOUT _ N) of the two-terminal amplifying circuit unit of the previous stage, respectively;

or, the amplifier further comprises a plurality of cascaded double-end amplifying circuit units and a second inter-stage signal transmission circuit, wherein a positive phase signal input end (VIN _ P) and a negative phase signal input end (VIN _ P) of the double-end amplifying circuit unit of the first stage are used for respectively receiving external positive phase signals and negative phase signals, and a positive phase signal input end (VIN _ P) and a negative phase signal input end (VIN _ P) of the double-end amplifying circuit unit of the other stage are used for respectively receiving signals output by a positive phase signal output end (VOUT _ P) and a negative phase signal output end (VOUT _ N) of the double-end amplifying circuit unit of the previous stage;

the second inter-stage signal transmission circuit is connected between two adjacent stages of double-end amplification circuit units and is used for blocking direct current signals in signals output by a positive phase signal output end (VOUT _ P) and a negative phase signal output end (VOUT _ N) of the double-end amplification circuit unit at the previous stage, and respectively outputting alternating current signals in the signals output by the positive phase signal output end (VOUT _ P) and the negative phase signal output end (VOUT _ N) to the double-end amplification circuit unit at the next stage;

and the second-stage signal transmission circuit is also used for providing preset direct-current bias voltage for the next-stage double-end amplification circuit unit.

Technical Field

The invention relates to the technical field of amplifiers, in particular to a thin film transistor integrated amplifier which can be applied to photoelectric sensing circuits and systems, power management circuits and systems, filter circuits and systems, temperature sensing circuits and systems, biomedical signal modulation and demodulation circuits, radio frequency signal identification and modulation and the like of the thin film transistor integrated amplifier.

Background

The rapid development of Thin Film Transistor (TFT) technology has promoted significant progress in active display technologies represented by large-size television displays and high-resolution small-size portable displays. In the conventional sense, the TFTs are only used as switching elements of the active display array for the transfer of display voltage signals. With the gradual realization of large-scale mass production of emerging display technologies such as Active Matrix Organic Light Emitting Display (AMOLED), micro light emitting diode display (micro LED) and the like, the possible application range of the TFT is greatly expanded, and the functions which can be realized comprise voltage-current conversion in display pixels, drive circuit integration around a panel, photoelectric sensing in the display panel and the like. Because the TFT is suitable for low-temperature large-area preparation, the TFT integrated circuit and the system thereof are beneficial to reducing the use of a driving IC and connecting wires thereof, and have wide development prospects in the next generation of electronic technologies such as photoelectric image sensors, photoelectric sensing in display arrays, flexible sensors and the like.

The TFT is only suitable for the integration of digital circuits in the past, and how to realize the functions of analog circuits by TFT integration has become the fundamental problem of TFT integrated circuit development nowadays. The TFT integrated amplifier is a most basic functional unit in the field of analog circuits, can be applied to TFT photoelectric sensing circuits, and can effectively suppress external noise while amplifying weak photoelectric signals. However, the existing TFT integrated amplifier circuit still has the technical problems of low gain, low bandwidth due to the influence of self parasitic capacitance, and low reliability.

Disclosure of Invention

The invention mainly solves the technical problem of how to improve the amplification gain of the amplifier integrated by the thin film transistor.

According to a first aspect, an embodiment provides a thin film transistor integrated amplifier comprising a single-ended amplification circuit unit comprising: an input amplification circuit and a bootstrap pull-up circuit;

the input amplifying circuit is used for converting the signal received by the signal input end of the input amplifying circuit and outputting the converted signal through the signal output end;

the bootstrap pull-up circuit is configured to pull up a potential of a signal output by the signal output terminal, and increase an output impedance of the bootstrap pull-up circuit, so as to stabilize a static operating point of the single-ended amplification circuit unit and improve an amplification gain of the single-ended amplification circuit unit, where the amplification gain of the single-ended amplification circuit unit is positively correlated to the output impedance of the bootstrap pull-up circuit.

According to a second aspect, an embodiment provides a thin film transistor integrated amplifier comprising a two-terminal amplification circuit unit, the two-terminal amplification circuit unit comprising: the positive-phase input circuit, the negative-phase input circuit, the positive-phase bootstrap pull-up circuit and the negative-phase bootstrap pull-up circuit;

the positive phase input circuit is used for converting a positive phase signal received by the positive phase signal input end and outputting the positive phase signal through the positive phase signal output end;

the negative phase input circuit is used for converting a negative phase signal received by the negative phase signal input end of the negative phase input circuit and outputting the negative phase signal through the negative phase signal output end;

the positive-phase bootstrap pull-up circuit is used for pulling up the potential of a positive-phase output signal output by the positive-phase signal output end and increasing the output impedance of the positive-phase bootstrap pull-up circuit so as to stabilize the static working point of the double-end amplification circuit unit and improve the amplification gain of the double-end amplification circuit unit;

the negative phase bootstrap pull-up circuit is used for pulling up the potential of a negative phase output signal output by a negative phase signal output end and increasing the output impedance of the negative phase bootstrap pull-up circuit so as to stabilize the static working point of the double-end amplification circuit unit and improve the amplification gain of the double-end amplification circuit unit.

According to the thin film transistor integrated amplifier of the embodiment, the amplifier comprises a single-ended amplification circuit unit, in the single-ended amplification circuit unit, the potential of the signal output by the signal output end is pulled up through the bootstrap pull-up circuit, so that the output signal can keep a higher level and has stronger driving capability, the output impedance of the bootstrap pull-up circuit is greatly increased through circuit topology design, the output impedance of the amplifier is the parallel value of the output impedance of the bootstrap pull-up circuit and the output impedance of the input amplification circuit, therefore, the output impedance of the amplifier is also increased to a certain extent by increasing the output impedance of the bootstrap pull-up circuit, and the amplification gain of the amplifier is increased by increasing the output impedance of the amplifier due to the fact that the amplification gain of the amplifier is in direct proportion to the product of the output impedance and transconductance.

According to the thin film transistor integrated amplifier of the above embodiment, the amplifier includes a double-ended amplifier circuit unit, in the double-ended amplifier circuit unit, the positive/negative phase bootstrap pull-up circuit pulls up the potential of the signal output from the positive/negative signal output terminal, so that the positive/negative phase output signal can maintain a higher level, and has a stronger driving capability, and the positive/negative phase bootstrap pull-up circuit greatly increases the output impedance of the positive/negative phase bootstrap pull-up circuit through the circuit topology design, since the output impedance of the amplifier is the parallel value of the output impedance of the positive/negative phase bootstrap pull-up circuit and the output impedance of the positive/negative phase input circuit, the output impedance of the positive/negative phase bootstrap pull-up circuit is increased to a certain extent, and since the amplification gain of the amplifier is proportional to the product of the output impedance and the transconductance, increasing the output impedance of the amplifier increases the amplification gain of the amplifier.

Drawings

FIG. 1 is a block diagram of an embodiment of a TFT integrated amplifier;

FIG. 2 is a circuit diagram of a single-ended amplification circuit cell of an embodiment;

FIG. 3 is a circuit diagram of a single-ended input single-ended output dual stage amplifier according to an embodiment;

FIG. 4 is a schematic diagram of transient response and AC analysis of a single-ended input single-ended output thin film transistor integrated amplifier circuit for different bootstrap pull-up configurations;

FIG. 5 is a block diagram of an embodiment of a TFT integrated amplifier;

FIG. 6 is a circuit diagram of a two-terminal amplification circuit unit of an embodiment;

fig. 7 is a circuit diagram of a two-terminal amplification circuit unit of another embodiment;

fig. 8 is a circuit diagram of a two-terminal amplification circuit unit of yet another embodiment;

fig. 9 is a circuit diagram of a two-terminal amplification circuit unit of yet another embodiment;

FIG. 10 is a schematic of AC analysis and spectral response of a two-terminal TFT integrated amplifier of stacked transistor configuration;

FIG. 11 is a schematic of AC analysis and spectral response of a two-terminal TFT integrated amplifier of stacked transistor configuration;

FIG. 12 is a circuit diagram of a hysteresis comparator based on a thin film transistor integrated amplifier;

FIG. 13 is a circuit diagram of a single oscillator circuit based on a thin film transistor integrated amplifier;

FIG. 14 is a circuit diagram of a voltage follower circuit based on a thin film transistor integrated amplifier;

FIG. 15 is a diagram illustrating transient response simulation results of a voltage follower circuit;

fig. 16 is a circuit diagram of a conventional thin film transistor integrated amplifier.

Detailed Description

The present invention will be described in further detail with reference to the following detailed description and accompanying drawings. Wherein like elements in different embodiments are numbered with like associated elements. In the following description, numerous details are set forth in order to provide a better understanding of the present application. However, those skilled in the art will readily recognize that some of the features may be omitted or replaced with other elements, materials, methods in different instances. In some instances, certain operations related to the present application have not been shown or described in detail in order to avoid obscuring the core of the present application from excessive description, and it is not necessary for those skilled in the art to describe these operations in detail, so that they may be fully understood from the description in the specification and the general knowledge in the art.

Furthermore, the features, operations, or characteristics described in the specification may be combined in any suitable manner to form various embodiments. Also, the various steps or actions in the method descriptions may be transposed or transposed in order, as will be apparent to one of ordinary skill in the art. Thus, the various sequences in the specification and drawings are for the purpose of describing certain embodiments only and are not intended to imply a required sequence unless otherwise indicated where such sequence must be followed.

The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" when used in this application, unless otherwise indicated, includes both direct and indirect connections (couplings).

A Thin Film Transistor (TFT) integrated amplifier circuit includes a single-ended input single-ended output single-stage type amplifier, a single-ended input single-ended output multi-stage type amplifier, a double-ended input double-ended output single-stage type amplifier, and a double-ended input double-ended output multi-stage type amplifier, wherein the single-stage type amplifier is different from the multi-stage type amplifier in that the single-stage type amplifier includes only one amplification circuit unit, the multi-stage type amplifier includes at least two cascaded amplification circuit units, the single-stage type amplifier is a basis of the multi-stage type amplifier, and for the multi-stage type amplifier, only the single-stage type amplifier has a large amplification gain, the cascade connection of the multi-stage amplification circuit units is possible, so that the. Referring to fig. 16, fig. 16 is a circuit diagram of a conventional tft integrated amplifier, in which (a) is a single-ended input single-ended output single-stage amplifier, and (b) is a double-ended input double-ended output single-stage amplifier, and the output impedance and transconductance of the two amplifier circuits are determined by the transistor parameters, so that it is difficult to achieve a large amplification gain.

In the embodiment of the invention, the output signal potential of the amplifier is pulled up through the circuit with the bootstrap pull-up structure, so that the output part of the amplifier has a proper direct current bias potential, the output impedance of the amplifier is increased, and the amplification gain of the amplifier is improved as the amplification gain of the amplifier is in direct proportion to the product of the output impedance and transconductance.

Note that the Thin Film Transistor (TFT) included in the amplifier circuit according to the embodiment of the present invention is not limited to a single type of thin film transistor, and may be an N-type (electron conductivity type) amorphous silicon (a-Si) TFT, an Indium Gallium Zinc Oxide (IGZO) TFT, a P-type (hole conductivity type) Low Temperature Polysilicon (LTPS) TFT, an OTFT, or another metal oxide TFT.