阅读说明：本技术 一种程控放大器 (Program control amplifier ) 是由 甘永进 王强 李琼 罗杨静 于 2019-11-26 设计创作，主要内容包括：本发明公开了一种程控放大器,涉及放大器的技术领域,解决了现有技术中的放大器滤波效果差且工作不稳定的技术问题。它包括主控模块和功率放大模块；还包括前置放大模块、椭圆带通滤波模块、可控增益放大模块和数模转换模块,前置放大模块的输入端输入输入信号,前置放大模块通过椭圆带通滤波模块与可控增益放大模块连接,可控增益放大模块的输出端与功率放大模块连接,主控模块通过数模转换模块与可控增益放大模块的使能端连接。本发明可对放大器的增益进行调节,不仅工作稳定,而且滤波效果好、波形无失真,频带范围也较宽。(The invention discloses a program control amplifier, relates to the technical field of amplifiers, and solves the technical problems of poor filtering effect and unstable work of the amplifier in the prior art. The device comprises a main control module and a power amplification module; the power amplifier comprises a power amplification module, a main control module and a pre-amplification module, and is characterized by further comprising a pre-amplification module, an elliptical band-pass filtering module, a controllable gain amplification module and a digital-to-analog conversion module, wherein an input signal is input at the input end of the pre-amplification module, the pre-amplification module is connected with the controllable gain amplification module through the elliptical band-pass filtering module, the output end of the controllable gain amplification module is connected with the power amplification module, and the main control module is connected with the enabling end of the controllable gain amplification module. The invention can adjust the gain of the amplifier, and has the advantages of stable work, good filtering effect, no waveform distortion and wider frequency band range.)

1. A program control amplifier comprises a main control module and a power amplification module, wherein the main control module is used for generating digital signals, and is characterized by also comprising a preamplification module, an elliptic band-pass filtering module, a controllable gain amplification module and a digital-to-analog conversion module;

the pre-amplification module is used for amplifying an input signal;

the elliptical band-pass filtering module filters the amplified input signal, attenuates the frequency band of the input signal outside the frequency band of the elliptical band-pass filtering module, and then transmits the filtered and attenuated input signal to the controllable gain amplifying module;

the digital-to-analog conversion module converts a digital signal sent by the main control module into an analog signal and transmits the analog signal to an enabling end of the controllable gain amplification module so as to control the gain multiple of the controllable gain amplification module;

the controllable gain amplification module changes the gain multiple of the controllable gain amplification module according to the analog signal, gains the input signal after filtering attenuation by the changed gain multiple, generates a gain signal, and transmits the gain signal to the power amplification module.

2. The programmable amplifier of claim 1, wherein the elliptical band pass filter module is an at least fifth order elliptical band pass filter module.

3. The programmable amplifier according to claim 2, wherein the elliptical band-pass filter module comprises a first capacitor (C1) and a third inductor (L3), one end of the first capacitor (C1) is connected to the output end of the pre-amplification module, the other end of the first capacitor (C1) is connected to one end of the third inductor (L3) through a first inductor (L1), a second capacitor (C2), a second inductor (L2) and a third capacitor (C3) which are sequentially connected in series, and the other end of the third inductor (L3) is connected to the input end of the controllable gain amplification module; the connection end of the first inductor (L1) and the second capacitor (C2) is grounded through a fourth inductor (L4) and a fourth capacitor (C4) which are connected in series, and the connection end of the first inductor (L1) and the second capacitor (C2) is also grounded through a fifth inductor (L5) and a fifth capacitor (C5) which are connected in series; the connection end of the second inductor (L2) and the third capacitor (C3) is grounded through a sixth inductor (L6) and a sixth capacitor (C6) which are connected in series, and the connection end of the second inductor (L2) and the third capacitor (C3) is also grounded through a seventh inductor (L7) and a seventh capacitor (C7) which are connected in series.

4. The programmable amplifier according to claim 1, wherein the controllable gain amplifying module comprises a controllable amplifying chip (U3) and a power supply terminal (VDD), the third pin of the controllable amplifying chip (U3) is connected to the output terminal of the elliptic band-pass filtering module through an eighth capacitor (C8), and the fourth pin of the controllable amplifying chip (U3) is grounded through a ninth capacitor (C9); a sixteenth pin of the controllable amplification chip (U3) is connected with an input end of the power amplification module through a tenth capacitor (C10), the sixteenth pin of the controllable amplification chip (U3) is further connected with a power supply end (VDD) through a first low-pass filtering unit, a fifteenth pin of the controllable amplification chip (U3) is grounded through an eleventh capacitor (C11), and a fifteenth pin of the controllable amplification chip (U3) is further connected with the power supply end (VDD) through a second low-pass filtering unit; and a twenty-fourth pin of the controllable amplification chip (U3) is connected with the output end of the digital-to-analog conversion module.

5. The programmable amplifier according to claim 4, wherein the controllable amplifier chip (U3) is of the type ADL 5330.

6. A programmable amplifier according to claim 4 or 5, characterised in that the digital-to-analogue conversion module comprises a DAC7621 conversion chip (U5), and the third pin of the DAC7621 conversion chip (U5) is connected to the twenty-fourth pin of the controllable amplification chip (U3).

7. The program-controlled amplifier according to claim 1, wherein the pre-amplifier module comprises a first amplifier unit and a second amplifier unit, an input terminal of the first amplifier unit receives the input signal and amplifies the input signal, an input terminal of the second amplifier unit receives the input signal amplified by the first amplifier unit and amplifies the amplified input signal again, the gain of the first amplifier unit is consistent with that of the second amplifier unit, and the gains of the first amplifier unit and the second amplifier unit are both fixed values.

8. The program-controlled amplifier according to claim 1, further comprising a key module, wherein the key module generates a trigger signal and transmits the trigger signal to the main control module, and the main control module generates a digital signal according to the trigger signal.

Technical Field

The present invention relates to the field of amplifier technology, and more particularly, to a programmable amplifier.

Background

With the progress of science and technology, the amplifier has significant breakthrough in the manufacturing process. At present, scientists in various countries continuously research and develop amplifiers, and hopefully, amplifier modules with stronger reliability and lower cost can be manufactured. And the amplifier with low working power supply voltage/current, low noise and distortion degree and integrated function is in the market, and the prospect is optimistic. At present, the amplifier on the market mainly adjusts the gain multiple of the amplifier directly through a singlechip of a main control module, but the requirement of the adjusting mode on the singlechip is higher, so that the amplifier not only occupies resources inside the singlechip, but also is easy to be interfered by the outside, and the system is unstable in work. In addition, the existing amplifier has the problems that the filtering effect on the input signal is poor, the signal is easy to be distorted, or the filtered signal carries an unnecessary frequency band to influence the work of the amplifier.

Disclosure of Invention

The invention aims to solve the technical problem of the prior art and provides a program control amplifier which is more stable in working and good in filtering effect.

The technical scheme of the invention is as follows: a program control amplifier comprises a main control module and a power amplification module, wherein the main control module is used for generating digital signals and also comprises a preamplification module, an elliptic band-pass filtering module, a controllable gain amplification module and a digital-to-analog conversion module;

the pre-amplification module is used for amplifying an input signal;

the elliptical band-pass filtering module filters the amplified input signal, attenuates the frequency band of the input signal outside the frequency band of the elliptical band-pass filtering module, and then transmits the filtered and attenuated input signal to the controllable gain amplifying module;

the digital-to-analog conversion module converts a digital signal sent by the main control module into an analog signal and transmits the analog signal to an enabling end of the controllable gain amplification module so as to control the gain multiple of the controllable gain amplification module;

the controllable gain amplification module changes the gain multiple of the controllable gain amplification module according to the analog signal, gains the input signal after filtering attenuation by the changed gain multiple, generates a gain signal, and transmits the gain signal to the power amplification module.

In a further improvement, the elliptical band-pass filtering module is an elliptical band-pass filtering module with at least five orders.

Furthermore, the elliptical band-pass filtering module comprises a first capacitor and a third inductor, one end of the first capacitor is connected with the output end of the pre-amplification module, the other end of the first capacitor is connected with one end of the third inductor through a first inductor, a second capacitor, a second inductor and a third capacitor which are sequentially connected in series, and the other end of the third inductor is connected with the input end of the controllable gain amplification module; the connecting end of the first inductor and the second capacitor is grounded through a fourth inductor and a fourth capacitor which are connected in series, and the connecting end of the first inductor and the second capacitor is grounded through a fifth inductor and a fifth capacitor which are connected in series; the connection end of the second inductor and the third capacitor is grounded through a sixth inductor and a sixth capacitor which are connected in series, and the connection end of the second inductor and the third capacitor is grounded through a seventh inductor and a seventh capacitor which are connected in series.

Furthermore, the controllable gain amplification module comprises a controllable amplification chip and a power supply end, a third pin of the controllable amplification chip is connected with the output end of the elliptical band-pass filtering module through an eighth capacitor, and a fourth pin of the controllable amplification chip is grounded through a ninth capacitor; a sixteenth pin of the controllable amplification chip is connected with the input end of the power amplification module through a tenth capacitor, the sixteenth pin of the controllable amplification chip is further connected with a power supply end through a first low-pass filtering unit, a fifteenth pin of the controllable amplification chip is grounded through an eleventh capacitor, and the fifteenth pin of the controllable amplification chip is further connected with the power supply end through a second low-pass filtering unit; and a twenty-fourth pin of the controllable amplification chip is connected with the digital-to-analog conversion module.

Furthermore, the controllable amplification chip is of the model number ADL 5330.

Furthermore, the digital-to-analog conversion module comprises a DAC7621 conversion chip, and a third pin of the DAC7621 conversion chip is connected with a twenty-fourth pin of the controllable amplification chip.

Furthermore, the preamplification module includes first amplification unit and second amplification unit, input signal is received to the input of first amplification unit, and will input signal enlargies, input signal after the input of second amplification unit received via first amplification unit enlargies, and will enlargie the back input signal enlargies again, first amplification unit is unanimous with the gain multiple of second amplification unit, just first amplification unit is the fixed value with the gain of second amplification unit.

Furthermore, the program control amplifier also comprises a key module, the key module generates a trigger signal and transmits the trigger signal to the main control module, and the main control module generates a digital signal according to the trigger signal.

Advantageous effects

The invention has the advantages that: an elliptical band-pass filtering module is added between the pre-amplification module and the controllable gain amplification module to perform filtering attenuation on the input signal amplified by the pre-amplification module, so that the frequency band range of the program control amplifier is improved, and the phenomenon of waveform distortion is effectively reduced. And the elliptic band-pass filtering module is used for filtering, so that the cut-off characteristic is good, the influence of the waveform outside the frequency band range on the program-controlled amplifier is effectively avoided, and the working effect of the program-controlled amplifier is better. In addition, a digital-to-analog conversion module is added between the main control module and the controllable gain amplification module, so that the problem that the controllable gain amplification module is directly controlled by the main control module to occupy the internal resources is avoided, and the digital-to-analog conversion module has a better and more stable data conversion effect, so that the control of the enabling end of the controllable gain amplification module is more stable and reliable, and the working stability of the program-controlled amplifier is effectively improved.

Drawings

FIG. 1 is a block diagram of the structure of the present invention;

FIG. 2 is a schematic circuit diagram of a pre-amplifier module according to the present invention;

FIG. 3 is a schematic circuit diagram of an elliptical band pass filter module according to the present invention;

FIG. 4 is a schematic diagram of a circuit structure of a controllable gain amplifier module according to the present invention;

FIG. 5 is a schematic circuit diagram of a power amplifier module according to the present invention;

FIG. 6 is a schematic diagram of a digital-to-analog conversion module according to the present invention;

fig. 7 is a schematic circuit diagram of a key module according to the present invention.

Detailed Description

The invention is further described below with reference to examples, but not to be construed as being limited thereto, and any number of modifications which can be made by anyone within the scope of the claims are also within the scope of the claims.

Referring to fig. 1, the program controlled amplifier of the present invention includes a main control module and a power amplification module, wherein the main control module is configured to generate a digital signal. The main control module comprises an MSP430 singlechip and is used for controlling the gain multiple of the program control amplifier. Referring to fig. 5, the power amplification module of the present embodiment includes a fourteenth capacitor C14, a fifteenth capacitor C15, and an AH101-G power amplification chip U4, wherein one end of the fourteenth capacitor C14 is connected to the output end of the controllable gain amplification module. Specifically, one end of the fourteenth capacitor C14 is connected to the sixteenth pin of the controllable amplifier chip U3. The other end of the fourteenth capacitor C14 is connected to the input terminal of the AH101-G power amplifier chip U4 through the first resistor R1, the output terminal of the AH101-G power amplifier chip U4 is connected to one end of the fifteenth capacitor C15, and the other end of the fifteenth capacitor C15 is the output terminal of the present program controlled amplifier. The output end of the AH101-G power amplification chip U4 is further connected with a power supply end through a tenth inductor L10 and a second resistor R2, and the connection end of the tenth inductor L10 and the second resistor R2 is grounded through a sixteenth capacitor C16. The program control amplifier also comprises a preamplification module, an elliptical band-pass filtering module, a controllable gain amplification module and a digital-to-analog conversion module.

The pre-amplification module is used for amplifying the input signal. The pre-amplification module comprises a first amplification unit and a second amplification unit, wherein the input end of the first amplification unit receives an input signal and amplifies the input signal, and the input end of the second amplification unit receives the input signal amplified by the first amplification unit and amplifies the amplified input signal again. The gain multiples of the first amplifying unit and the second amplifying unit of the embodiment are consistent; and the gains of the first amplifying unit and the second amplifying unit are fixed values. Specifically, referring to fig. 2, the circuit structures of the first amplification unit and the second amplification unit are identical, and the first amplification chip U1 of the first amplification unit and the second amplification chip U2 of the second amplification unit are both OPA 695. The pre-amplification module of this embodiment fixes the value of the amplification gain to 20dB through the circuit structure shown in fig. 2.

The elliptical band-pass filtering module filters the amplified input signal, attenuates the frequency band of the input signal outside the frequency band of the elliptical band-pass filtering module, and then transmits the filtered and attenuated input signal to the controllable gain amplifying module. In this embodiment, the elliptical band-pass filtering module is an elliptical band-pass filtering module with at least five orders. Preferably, the elliptic band-pass filtering module is a five-order elliptic band-pass filtering module and is used for filtering clutter in an output signal of the pre-amplification module, so that the program-controlled amplifier can work more stably; meanwhile, the band range of the program control amplifier is greatly improved by the five-order elliptical band-pass filtering module, and the phenomenon of waveform distortion is effectively reduced.

Referring to fig. 3, in particular, the elliptical band pass filter module includes a first capacitor C1 and a third inductor L3. One end of a first capacitor C1 is connected with the output end of the pre-amplification module, the other end of the first capacitor C1 is connected with one end of a third inductor L3 through a first inductor L1, a second capacitor C2, a second inductor L2 and a third capacitor C3 which are sequentially connected in series, and the other end of the third inductor L3 is connected with the input end of the controllable gain amplification module. The connection end of the first inductor L1 and the second capacitor C2 is grounded through a fourth inductor L4 and a fourth capacitor C4 which are connected in series, and the connection end of the first inductor L1 and the second capacitor C2 is also grounded through a fifth inductor L5 and a fifth capacitor C5 which are connected in series. The connection end of the second inductor L2 and the third capacitor C3 is grounded through a sixth inductor L6 and a sixth capacitor C6 which are connected in series, and the connection end of the second inductor L2 and the third capacitor C3 is also grounded through a seventh inductor L7 and a seventh capacitor C7 which are connected in series. The elliptical band-pass filter module of the embodiment can provide a frequency bandwidth in the range of 250MHz-350MHz, and the fluctuation in the frequency band is small. The elliptic band-pass filtering module of the embodiment is subjected to experimental simulation through professional filter design software Filtersolution, and the signal fluctuation in a frequency band is less than 2 dB; and when the frequency of the input signal is less than or equal to 200MHz or less than or equal to 400MHz, the attenuation of the elliptic band-pass filter module to the signal is more than 20dB, the fluctuation is small, the cut-off characteristic is good, the influence of a waveform outside a frequency band range on the program control amplifier is effectively avoided, the working efficiency is higher, and the effect is better.

The digital-to-analog conversion module converts the digital signals sent by the main control module into analog signals and transmits the analog signals to the enabling end of the controllable gain amplification module so as to control the gain multiple of the controllable gain amplification module. A digital-to-analog conversion module is added between the main control module and the controllable gain amplification module and is used for increasing the working stability of the program control amplifier; and the digital-to-analog conversion module can also avoid excessively occupying the resources of the main control module, so that the operation effect of the main control module is poor. The controllable gain amplification module changes the gain multiple of the controllable gain amplification module according to the analog signal, gains the filtered and attenuated input signal by the changed gain multiple, generates a gain signal, and transmits the gain signal to the power amplification module.

Referring to fig. 4, in particular, the controllable gain amplifying module includes a controllable amplifying chip U3 and a power supply terminal VDD. The model of the controllable amplification chip U3 is ADL 5330. And a third pin of the controllable amplification chip U3 is connected with the output end of the elliptic band-pass filtering module through an eighth capacitor C8. Specifically, the third pin of the controllable amplifier chip U3 is connected to the output terminal of the third inductor L3 through the eighth capacitor C8. The fourth pin of the controllable amplification chip U3 is grounded through a ninth capacitor C9; a sixteenth pin of the controllable amplification chip U3 is connected with the input end of the power amplification module through a tenth capacitor C10, the sixteenth pin of the controllable amplification chip U3 is further connected with a power supply terminal VDD through a first low-pass filtering unit, a fifteenth pin of the controllable amplification chip U3 is grounded through an eleventh capacitor C11, and a fifteenth pin of the controllable amplification chip U3 is further connected with the power supply terminal VDD through a second low-pass filtering unit; and a twenty-fourth pin of the controllable amplification chip U3 is connected with the digital-to-analog conversion module. The first low-pass filtering unit comprises an eighth inductor L8 and a twelfth capacitor C12, a sixteenth pin of the controllable amplification chip U3 is connected with one end of the eighth inductor L8, the other end of the eighth inductor L8 is connected with a power supply terminal VDD, and the eighth inductor L3538 is further grounded through the twelfth capacitor C12. The second low-pass filtering unit comprises a ninth inductor L9 and a thirteenth capacitor C13, a fifteenth pin of the controllable amplification chip U3 is connected with one end of the ninth inductor L9, and the other end of the ninth inductor L9 is connected with the power supply terminal VDD and is further grounded through the thirteenth capacitor C13. Referring to fig. 6, the digital-to-analog conversion module includes a DAC7621 conversion chip U5, and the third pin of the DAC7621 conversion chip U5 is connected to the twenty-fourth pin of the controllable amplification chip U3. The program-controlled amplifier receives a data signal sent by the MSP430 single chip microcomputer through the DAC7621 conversion chip U5, generates an analog signal according to the data signal, and changes the voltage of the twenty-fourth pin of the ADL5330 controllable amplification chip U3 through the analog signal, so that the gain multiple of the ADL5330 controllable amplification chip U3 is changed, and the purpose of controllable gain of the program-controlled amplifier is achieved. The gain of the ADL5330 controllable amplification chip U3 of the embodiment is adjustable within the range of-31 dB to 22dB, and the controllable gain range is large, so that the application range is wider.

Referring to fig. 7, the program-controlled amplifier further includes a key module, the key module generates a trigger signal and transmits the trigger signal to the main control module, and the main control module generates a digital signal according to the trigger signal. The key module of this embodiment includes four key trigger units with the same circuit structure, and the four key trigger units are connected with four I/O pins of the MSP430 singlechip in a one-to-one correspondence manner. The MSP430 singlechip reads the trigger signals of the four key trigger units and generates a digital signal for controlling the gain of the ADL5330 controllable amplification chip U3 according to the rough signal. The programmable amplifier of the embodiment can be stepped by 5dB through the key trigger unit, and the gain from 0dB to 40dB can be controlled.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various changes and modifications without departing from the structure of the invention, which will not affect the effect of the invention and the practicability of the patent.