Driving amplification circuit, driving amplification device and optical transmitter

Abstract

The invention discloses a driving amplification circuit, a driving amplification device and an optical transmitter, and relates to the technical field of driving amplification circuits, and the driving amplification circuit comprises a variable gain amplification circuit with an equalization function, a continuous time linear equalization circuit and an output amplification stage circuit with an equalization function, and the variable gain amplification circuit, the output amplification stage circuit and the output amplification stage circuit have balance points with different frequencies. According to the driving amplification circuit, on the basis of a continuous time linear equalization circuit, a variable gain amplification circuit and an output amplification stage circuit of an existing driving amplification circuit are optimized, and the variable gain amplification circuit and the output amplification stage circuit are both improved to have an equalization function; and the variable gain amplification circuit, the output amplification stage circuit and the output amplification stage circuit are set to be balance points with different frequencies, so that the whole driving amplification circuit can perform gain compensation on a plurality of signals with different frequencies.

Description

Technical Field

[0001] The present invention relates to the technical field of drive amplifier circuits, and in particular to a drive amplifier circuit, a drive amplifier device and an optical transmitter. Background Art

[0002] With the rapid development of large models, cloud computing, big data and other applications, new challenges have been brought to the new generation of information data transmission, and modern optical communication systems have increasingly higher requirements for data transmission bandwidth.

[0003] In high-speed data transmission, the signal will be affected by the channel transmission characteristics, resulting in signal distortion and distortion. It is usually necessary to add an equalization circuit to the driving amplifier circuit to compensate the signal gain, restore the received signal to its original shape, and improve the signal quality and data transmission performance.

[0004] The traditional driving amplifier circuit mainly includes a continuous time linear equalization circuit, a variable gain amplifier and an output amplifier circuit, wherein the continuous time linear equalization circuit is used to equalize the signal and perform gain compensation on the signal. However, the frequency of gain compensation in this way is relatively single and the frequency of gain compensation is low, which cannot meet the requirements of ultra-high rate transmission. Summary of the invention

[0005] The embodiments of the present invention provide a driving amplifier circuit, a driving amplifier device and an optical transmitter to solve the technical problem that the existing driving amplifier circuit in the related art only uses a continuous time linear equalization circuit to equalize the signal and can only perform gain compensation on a certain frequency signal.

[0006] In a first aspect, a driving amplifier circuit is provided, comprising:

[0007] A variable gain amplifier circuit with an equalization function, a continuous time linear equalization circuit and an output amplifier stage circuit with an equalization function are connected in sequence, and the variable gain amplifier circuit, the output amplifier stage circuit and the output amplifier stage circuit have equalization points of different frequencies.

[0008] In some embodiments, the variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit are all distributed circuit structures and are all provided with negative feedback circuit structures, and the frequency responses in the negative feedback circuit structures of the variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit are different.

[0009] In some embodiments, the distributed circuit structure of the variable gain amplifier circuit includes multiple first differential input transmission lines, a first terminal matching resistor, at least two variable gain amplifier units, multiple first differential output transmission lines and a first load terminal resistor, and each of the variable gain amplifier units is provided with a negative feedback circuit structure.

[0010] In some embodiments, each of the variable gain amplifier units includes 6 first-type triodes, 2 bias voltages, 2 first-type constant current sources, a first resistor and a first capacitor.

[0011] In some embodiments, the distributed circuit structure of the continuous time linear equalization circuit includes multiple second differential input transmission lines, second terminal matching resistors, at least 2 continuous time linear equalization units, multiple second differential output transmission lines and second load terminal resistors, and each of the continuous time linear equalization units is provided with a negative feedback circuit structure.

[0012] In some embodiments, each of the continuous time linear equalization units includes two second type transistors, two second type constant current sources, a second resistor and a second capacitor.

[0013] In some embodiments, the distributed circuit structure of the output amplifier stage circuit includes multiple third differential input transmission lines, a third terminal matching resistor, at least 2 output amplifier stage units, multiple third differential output transmission lines and a fourth terminal matching resistor, and each of the output amplifier stage units is provided with a negative feedback circuit structure.

[0014] In some embodiments, each of the output amplifier stage units includes four third-type triodes, two third-type constant current sources, a third resistor and a third capacitor.

[0015] In a second aspect, a driving amplifier device is provided, comprising the aforementioned driving amplifier circuit.

[0016] In a third aspect, an optical transmitter is provided, comprising the aforementioned driving and amplifying device.

[0017] The beneficial effects brought about by the technical solution provided by the present invention include:

[0018] The embodiment of the present invention provides a driving amplifier circuit, a driving amplifier device and an optical transmitter. The driving amplifier circuit optimizes the variable gain amplifier circuit and the output amplifier stage circuit of the existing driving amplifier circuit on the basis of a continuous time linear equalization circuit, and improves the variable gain amplifier circuit and the output amplifier stage circuit to have an equalization function, and sets the variable gain amplifier circuit, the output amplifier stage circuit and the output amplifier stage circuit to have equalization points with different frequencies, so that the entire driving amplifier circuit can perform gain compensation on multiple different frequency signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 A schematic diagram of the structure of a driving amplifier circuit provided by an embodiment of the present invention;

[0021] Figure 2 A schematic diagram of the structure of a variable gain amplifier circuit provided by an embodiment of the present invention;

[0022] Figure 3 A schematic diagram of the structure of a continuous time linear equalization circuit provided by an embodiment of the present invention;

[0023] Figure 4 A schematic diagram of the structure of an output amplifier stage circuit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] The embodiment of the present invention provides a driving amplifier circuit, which can solve the technical problem that the existing driving amplifier circuit only uses a continuous time linear equalization circuit to equalize the signal and can only perform gain compensation on a certain frequency signal.

[0026] See also Figure 1 As shown, an embodiment of the present invention provides a driving amplifier circuit, comprising: a variable gain amplifier circuit (DVGA) with an equalization function, a continuous time linear equalization circuit (DCTLE) and an output amplifier circuit (DA) with an equalization function, which are connected in sequence, and the variable gain amplifier circuit, the output amplifier circuit and the output amplifier circuit have equalization points of different frequencies. The connection order of the variable gain amplifier circuit, the output amplifier circuit and the output amplifier circuit can be adjusted.

[0027] The driving amplifier circuit in the embodiment of the present invention optimizes the existing variable gain amplifier circuit and output amplifier stage circuit on the basis of the continuous time linear equalization circuit, and improves the variable gain amplifier circuit and the output amplifier stage circuit to have an equalization function, and sets the variable gain amplifier circuit, the output amplifier stage circuit and the output amplifier stage circuit to have equalization points with different frequencies, so that the entire driving amplifier circuit can perform gain compensation on multiple different frequency signals.

[0028] As an optional implementation, in an embodiment of the invention, the variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit are all distributed circuit structures and are all provided with negative feedback circuit structures, and the frequency responses in the negative feedback circuit structures of the variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit are different.

[0029] The variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit use a distributed structure to distribute the amplification function in multiple parts of the circuit, so as to achieve high gain and large bandwidth. The variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit are all provided with a negative feedback circuit structure, and the frequency responses in the negative feedback circuit structures of the variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit are different, so that the variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit can have equalization points with different frequencies.

[0030] See also Figure 2 As shown, the distributed circuit structure of the variable gain amplifier circuit includes multiple first differential input transmission lines Lin1, a first terminal matching resistor Rterm1, at least 2 variable gain amplifier units, multiple first differential output transmission lines Lout1 and a first load terminal resistor RL1, and each of the variable gain amplifier units is provided with a negative feedback circuit structure.

[0031] See also Figure 2As shown, two adjacent variable gain amplifying units are connected via a first differential input transmission line and a first differential output transmission line, the input end of the first variable gain amplifying unit is connected to a differential input signal via the first differential input transmission line, and the input end of the last variable gain amplifying unit is connected to a first terminal matching resistor via the first differential input transmission line; the output end of the first variable gain amplifying unit is connected to a first load terminal resistor via a first differential output transmission line and then to a power supply VDD, the output end of the last variable gain amplifying unit is connected to the continuous time linear equalization circuit of the subsequent stage via the first differential output transmission line, and the output end of the last variable gain amplifying unit outputs a differential output signal Vout1 to the continuous time linear equalization circuit.

[0032] By providing at least two variable gain amplifying units in the distributed circuit structure of the variable gain amplifying circuit, a better equalization effect (i.e., a gain with a higher equalization frequency) can be achieved. In theory, the equalization effect is n times the equalization gain of a single variable gain amplifying unit.

[0033] Secondly, the bandwidth of the traditional driving amplifier circuit is limited by the main pole frequency of the circuit, resulting in limited circuit bandwidth and balancing effect. The embodiment of the present invention can neutralize the equivalent capacitance of the input and output nodes through the first differential output transmission line and the inductance in the first differential output transmission line, thereby breaking through the limitation of the main pole frequency and achieving a higher frequency balancing effect.

[0034] Again, when the high-frequency signal is transmitted on the first differential output transmission line and the first differential output transmission line, the electromagnetic wave will propagate along the first differential output transmission line and the first differential output transmission line in the form of a traveling wave, and reflection and transmission will occur at the same time. By designing the shape, width, medium and other parameters of the first differential output transmission line and the first differential output transmission line, impedance matching with the variable gain amplifier unit can be achieved, thereby reducing signal reflection and loss.

[0035] Each of the variable gain amplifier units includes 6 first-type triodes, 2 bias voltages, 2 first-type constant current sources, a first resistor Rs1 and a first capacitor Cs1.

[0036] Among them, 6 first-class transistors Q 11 , Q 12 , Q 13 , Q 14 , Q 15 , Q 16 Connect to form a symmetrical structure, transistor Q 11、 Transistor Q 12 , transistor Q 14、 Transistor Q 15 The collector of the first differential output transmission line is connected to the transistor Q 13And transistor Q 16 The base of transistor Q 11、 Transistor Q 15 The base of transistor Q is connected to the bias voltage Vctrln. 12、 Transistor Q 14 The base of transistor Q is connected to the bias voltage Vctrlp. 13 And transistor Q 16 The emitter of 11 , constant current source I 12 The first resistor Rs1 and the first capacitor Cs1 are connected to the ground, and the two ends of the first resistor Rs1 and the first capacitor Cs1 are connected to the transistor Q 13 And transistor Q 16 The emitter of transistor Q 13 And transistor Q 16 The emitter of the amplifier is added with a first parallel resistor Rs1 and a first parallel capacitor Cs1 of negative feedback to form a negative feedback circuit structure, and an extra pole and an extra zero are artificially introduced to realize the balancing function of the variable gain amplifier unit.

[0037] See also Figure 3 As shown, the distributed circuit structure of the continuous time linear equalization circuit includes multiple second differential input transmission lines Lin2, a second terminal matching resistor Rterm2, at least 2 continuous time linear equalization units, multiple second differential output transmission lines Lout2 and a second load terminal resistor RL2, and each of the continuous time linear equalization units is provided with a negative feedback circuit structure.

[0038] See also Figure 3 As shown, two adjacent continuous time linear equalization units are connected via a second differential input transmission line and a second differential output transmission line, the input end of the first continuous time linear equalization unit is connected to the differential input signal Vin2 (i.e., the differential output signal Vout1) via the second differential input transmission line, and the input end of the last continuous time linear equalization unit is connected to the second terminal matching resistor via the second differential input transmission line; the output end of the first variable gain amplifier unit is connected to the second load terminal resistor via the second differential output transmission line and then to the power supply VDD, and the output end of the last continuous time linear equalization unit is connected to the output amplifier stage circuit of the subsequent stage via the second differential output transmission line.

[0039] Similarly, by providing at least two of the time linear equalization units in the distributed circuit structure of the time linear equalization circuit, a better equalization effect (ie, a higher gain at the equalization frequency) can be achieved. In theory, the equalization effect is n times the equalization gain of a single time linear equalization unit.

[0040] Secondly, the bandwidth of the traditional driving amplifier circuit is limited by the main pole frequency of the circuit, resulting in limited circuit bandwidth and balancing effect. The embodiment of the present invention can neutralize the equivalent capacitance of the input and output nodes through the first differential output transmission line and the inductance in the first differential output transmission line, thereby breaking through the limitation of the main pole frequency and achieving a higher frequency balancing effect.

[0041] Again, when the high-frequency signal is transmitted on the first differential output transmission line and the first differential output transmission line, the electromagnetic wave will propagate along the first differential output transmission line and the first differential output transmission line in the form of a traveling wave, and reflection and transmission will occur at the same time. By designing the shape, width, medium and other parameters of the first differential output transmission line and the first differential output transmission line, impedance matching with the variable gain amplifier unit can be achieved, thereby reducing signal reflection and loss.

[0042] See also Figure 3 As shown, each of the continuous time linear equalization units includes two second type triodes, two second type constant current sources, a second resistor Rs2 and a second capacitor Cs2.

[0043] Among them, two first-class transistors Q 21 , Q 22 Connect to form a symmetrical structure, transistor Q 21 And transistor Q 22 The collector of transistor Q 21 And transistor Q 22 The base of transistor Q 21 And transistor Q 22 The emitter of 21 , constant current source I 22 The second resistor Rs2 and the second capacitor Cs2 are connected to the ground, and the two ends of the second resistor Rs2 and the second capacitor Cs2 are connected to the transistor Q 21 And transistor Q 22 The emitter of transistor Q 21 And transistor Q 22 A second parallel resistor Rs2 and a second parallel capacitor Cs2 of negative feedback are added to the emitter to form a negative feedback circuit structure, and an additional pole and an additional zero are artificially introduced to realize the equalization function of the continuous time linear equalization unit.

[0044] See also Figure 4 As shown, the distributed circuit structure of the output amplifier stage circuit includes multiple third differential input transmission lines Lin3, a third terminal matching resistor Rterm3, at least 2 output amplifier stage units, multiple third differential output transmission lines Lout3 and a fourth terminal matching resistor Rterm4.

[0045] See also Figure 4As shown, two adjacent output amplifier stage units are connected via a third differential input transmission line and a third differential output transmission line, the input end of the first output amplifier stage unit is connected to the differential input signal Vin3 (i.e., the differential output signal Vout2) via the third differential input transmission line, and the input end of the last output amplifier stage unit is connected to the third terminal matching resistor via the second differential input transmission line; the output end of the first output amplifier stage unit is connected to the fourth load terminal resistor via the third differential output transmission line, and the output end of the last output amplifier stage unit is connected to the subsequent circuit via the third differential output transmission line.

[0046] Similarly, by providing at least two output amplifier stage units in the distributed circuit structure of the output amplifier stage circuit, a better balancing effect can be achieved. Theoretically, the balancing effect is n times the balancing gain of a single output amplifier stage unit.

[0047] Secondly, the bandwidth of the traditional driving amplifier circuit is limited by the main pole frequency of the circuit, resulting in limited circuit bandwidth and balancing effect. The embodiment of the present invention can neutralize the equivalent capacitance of the input and output nodes through the third differential output transmission line and the inductance in the third differential output transmission line, thereby breaking through the limitation of the main pole frequency and achieving a higher frequency balancing effect.

[0048] Again, when the high-frequency signal is transmitted on the third differential output transmission line and the third differential output transmission line, the electromagnetic wave will propagate along the third differential output transmission line and the third differential output transmission line in the form of a traveling wave, and reflection and transmission will occur at the same time. By designing the shape, width, medium and other parameters of the third differential output transmission line and the third differential output transmission line, impedance matching with the variable gain amplifier unit can be achieved, thereby reducing signal reflection and loss.

[0049] As an optional implementation, in an embodiment of the invention, see Figure 4 As shown, each of the output amplifier stage units includes four third-type triodes, two third-type constant current sources, a third resistor Rs3 and a third capacitor Cs3.

[0050] Among them, 4 first-class transistors Q 31 , Q 32 , Q 33 , Q 34 Connect to form a symmetrical structure, transistor Q 31 And transistor Q 33 The collector of the third differential output transmission line is connected to the transistor Q 32 And transistor Q 34 The base of transistor Q 32 And transistor Q 34 The emitter of 31, constant current source I 32 The third resistor Rs3 and the third capacitor Cs3 are connected to the ground, and the two ends of the third resistor Rs3 and the third capacitor Cs3 are connected to the transistor Q 32 And transistor Q 34 The emitter of transistor Q 32 And transistor Q 34 A third parallel resistor Rs3 and a third parallel capacitor Cs3 of negative feedback are added to the emitter to form a negative feedback circuit structure, an extra pole and an extra zero are artificially introduced, and the balancing function of the output amplifier stage unit is realized.

[0051] A negative feedback circuit structure is provided in the three-stage circuits of the variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit, and the parallel resistors and parallel capacitors used in the negative feedback structure of each stage are of different sizes to achieve different frequency responses. By allocating suitable parallel resistors and parallel capacitors to each structure, the equalization effect of multiple frequencies can be achieved, so that the entire driving amplifier circuit can perform gain compensation on multiple different frequency signals.

[0052] An embodiment of the present invention further provides a driving amplifier device, comprising the aforementioned driving amplifier circuit.

[0053] An embodiment of the present invention further provides an optical transmitter, comprising the aforementioned driving and amplifying device.

[0054] In the description of the present invention, it should be noted that the terms "upper", "lower", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0055] It should be noted that, in the present invention, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0056] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but should conform to the widest scope consistent with the principles and novel features of the present invention.

Claims

1. A driving amplifier circuit, characterized in that: include: A variable gain amplifier circuit with an equalization function, a continuous time linear equalization circuit and an output amplifier stage circuit with an equalization function are connected in sequence, and the variable gain amplifier circuit, the output amplifier stage circuit and the output amplifier stage circuit have equalization points of different frequencies.

2. The driving amplifier circuit according to claim 1, characterized in that: The variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit are all distributed circuit structures and are all provided with negative feedback circuit structures, and the frequency responses in the negative feedback circuit structures of the variable gain amplifier circuit, the continuous time linear equalization circuit and the output amplifier stage circuit are different.

3. The driving amplifier circuit according to claim 2, characterized in that: The distributed circuit structure of the variable gain amplifier circuit includes multiple first differential input transmission lines, a first terminal matching resistor, at least two variable gain amplifier units, multiple first differential output transmission lines and a first load terminal resistor, and each of the variable gain amplifier units is provided with a negative feedback circuit structure.

4. The driving amplifier circuit according to claim 3, characterized in that: Each of the variable gain amplifying units includes 6 first-type triodes, 2 bias voltages, 2 first-type constant current sources, a first resistor and a first capacitor.

5. The driving amplifier circuit according to claim 2, characterized in that: The distributed circuit structure of the continuous time linear equalization circuit includes multiple second differential input transmission lines, second terminal matching resistors, at least two continuous time linear equalization units, multiple second differential output transmission lines and second load terminal resistors, and each of the continuous time linear equalization units is provided with a negative feedback circuit structure.

6. The driving amplifier circuit according to claim 5, characterized in that: Each of the continuous time linear equalization units includes two second type triodes, two second type constant current sources, a second resistor and a second capacitor.

7. The driving amplifier circuit according to claim 2, characterized in that: The distributed circuit structure of the output amplifier stage circuit includes multiple third differential input transmission lines, a third terminal matching resistor, at least 2 output amplifier stage units, multiple third differential output transmission lines and a fourth terminal matching resistor, and each of the output amplifier stage units is provided with a negative feedback circuit structure.

8. The driving amplifier circuit according to claim 7, characterized in that: Each of the output amplifier stage units includes four third-type triodes, two third-type constant current sources, a third resistor and a third capacitor.

9. A driving amplifier device, characterized in that: The invention comprises the driving amplifier circuit as described in any one of claims 1 to 8.

10. An optical transmitter, characterized in that: It comprises the driving and amplifying device as claimed in claim 9.

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