Adjustable reference source control circuit

Abstract

The utility model discloses an adjustable reference source control circuit, which relates to the field of reference voltage adjusting circuits and comprises an adjusting level conversion isolation module, a logic processing module and a digital-to-analog conversion module. The level conversion isolation circuit is adjusted to be a level conversion circuit and a level isolation circuit. The connection between the level conversion isolation module and the logic processing module is adjusted, and the digital-to-analog conversion module is connected with the logic processing module. The level conversion circuit converts an external voltage regulation signal into a first level signal conforming to the level isolation circuit, and then the first level signal is converted into a second level signal conforming to the logic processing module through the level isolation circuit. The second level signal is converted into an IIC signal which can be recognized by the digital-to-analog conversion circuit through the logic processing module, the digital-to-analog conversion circuit is controlled to output voltage, the digital-to-analog conversion module adopts a 15Bit digital-to-analog converter, and the reference voltage adjusting precision is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of reference voltage regulating circuit, in particular to an adjustable reference source control circuit. BACKGROUND

[0002] With the development of digital technology, the online adjustable reference voltage plays an important role in the pulse amplitude discrimination of digital nuclear measurement instrument system. Digital potentiometer is an imported component widely used in nuclear measurement instrument system, and is a key component in nuclear measurement instrument system. With the increasing international competition, the problem of key components "neck" is becoming increasingly serious. It is urgent to break the passive situation of long-term dependence on imported key components and meet the requirements of China's independent controllability of key components and key equipment.

[0003] The imported 10Bit digital potentiometer used in the nuclear measurement instrument system has low resolution, resulting in low regulation accuracy of the reference voltage. CONTENT OF THE INVENTION

[0004] The purpose of the present application is to provide an adjustable reference source control circuit to improve the regulation accuracy of the reference voltage.

[0005] To achieve the above purpose, the present application provides the following scheme:

[0006] The present application provides an adjustable reference source control circuit, which comprises an adjusting level conversion isolation module, a logic processing module and a digital-to-analog conversion module; the adjusting level conversion isolation module comprises a level conversion circuit and a level isolation circuit connected in sequence; the level isolation circuit is connected with the logic processing module; the digital-to-analog conversion module is connected with the logic processing module; the digital-to-analog conversion module comprises a 15Bit digital-to-analog converter;

[0007] The level conversion circuit is used for converting an external voltage adjusting signal into a first level signal; the level isolation circuit is used for converting the first level signal into a second level signal;

[0008] The logic processing module is used for converting the second level signal into a voltage adjusting digital signal;

[0009] The digital-to-analog conversion module is used for converting the voltage adjusting digital signal into a voltage adjusting analog signal.

[0010] Optionally, it further comprises a storage module; the storage module is connected with the logic processing module; the storage module is used for storing the voltage adjusting digital signal.

[0011] Optionally, the storage module is an electrically erasable programmable read-only memory.

[0012] Optionally, the logic processing module is a complex programmable logic device.

[0013] Optionally, the level conversion circuit comprises three voltage division units; the voltage division unit comprises a first voltage division resistor, a second voltage division resistor and a current limiting resistor connected in sequence; the current limiting resistor is connected with the level isolation circuit.

[0014] Optionally, the level isolation circuit is a digital isolator.

[0015] Optionally, the digital-to-analog conversion module further comprises a first pull-up resistor, a second pull-up resistor, a first capacitor and a second capacitor; one end of the first pull-up resistor, one end of the second pull-up resistor, one end of the first capacitor and one end of the second capacitor are connected with the 15Bit digital-to-analog converter; the other end of the first pull-up resistor and the other end of the second pull-up resistor are connected with a power supply; the other end of the first capacitor and the other end of the second capacitor are grounded.

[0016] According to the specific embodiments provided in the application, the following technical effects are disclosed:

[0017] The application provides an adjustable reference source control circuit comprising an adjusting level conversion isolation module, a logic processing module and a digital-to-analog conversion module; the adjusting level conversion isolation circuit is a level conversion circuit and a level isolation circuit. The adjusting level conversion isolation module is connected with the logic processing module, and the digital-to-analog conversion module is connected with the logic processing module. The level conversion circuit converts an external voltage adjusting signal into a first level signal conforming to the level isolation circuit, and then the first level signal is converted into a second level signal conforming to the logic processing module through the level isolation circuit. The second level signal is converted into an IIC signal recognizable by the digital-to-analog conversion circuit through the logic processing module, so as to control the output voltage of the digital-to-analog conversion circuit. The digital-to-analog conversion module adopts a 15Bit digital-to-analog converter, thereby improving the reference voltage adjusting precision. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings described below are only some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0019] Figure 1 A schematic diagram of an adjustable reference source control circuit is provided for an embodiment of the application.

[0020] Figure 2 A schematic diagram of an adjusting level conversion isolation module is provided.

[0021] Figure 3 a schematic diagram of a digital-to-analog conversion module;

[0022] Figure 4 a schematic diagram of a storage module;

[0023] Figure 5 a schematic diagram of a logic processing module.

[0024] Fig. 1 is a logic processing module; Fig. 2 is an adjusting level conversion isolation module; Fig. 3 is a digital-to-analog conversion module; and Fig. 4 is a storage module. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0026] The above purposes, features and advantages of the present application will be more apparent and understandable. The present application will be described in further detail below with reference to the drawings and specific embodiments.

[0027] In an exemplary embodiment, as shown in Figure 1 An adjustable reference source control circuit is provided, which can be applied to a nuclear industry digitized instrument system, adopts a complex programmable logic device (CPLD) as a logic control chip, has high real-time performance, and includes an adjusting level conversion isolation module 2, a logic processing module 1, a digital-to-analog conversion module 3 and a storage module 4. The adjusting level conversion isolation module includes a level conversion circuit and a level isolation circuit connected in sequence. The level isolation circuit is connected with the logic processing module. The digital-to-analog conversion module is connected with the logic processing module. The digital-to-analog conversion module includes a 15-bit digital-to-analog converter. The storage module is connected with the logic processing module.

[0028] The level conversion circuit is configured to convert an external voltage adjusting signal into a first level signal. The level isolation circuit is configured to convert the first level signal into a second level signal.

[0029] The logic processing module is configured to convert the second level signal into a voltage adjusting digital signal. The logic processing module is a complex programmable logic device.

[0030] The digital-to-analog conversion module is configured to convert the voltage adjusting digital signal into a voltage adjusting analog signal.

[0031] The storage module is used for storing the voltage adjustment digital signal. The storage module is an electrically erasable programmable read-only memory.

[0032] As an optional implementation, the level conversion circuit includes three voltage division units; the voltage division unit includes a first voltage division resistor, a second voltage division resistor and a current limiting resistor connected in sequence; the current limiting resistor is connected with the level isolation circuit. The level isolation circuit is a digital isolator.

[0033] As an optional implementation, the digital-to-analog conversion module further includes a first pull-up resistor, a second pull-up resistor, a first capacitor and a second capacitor; one end of the first pull-up resistor, one end of the second pull-up resistor, one end of the first capacitor and one end of the second capacitor are all connected with the 15-bit digital-to-analog converter; the other end of the first pull-up resistor and the other end of the second pull-up resistor are both connected with a power supply; the other end of the first capacitor and the other end of the second capacitor are both grounded.

[0034] In actual application, the adjustment level conversion isolation module 2 includes a level conversion circuit and a level isolation circuit. As shown in Figure 1 The adjustment level conversion isolation module 2 is connected with the general I / O pin of the CPLD, the digital-to-analog conversion module 3 is connected with the general I / O pin of the CPLD, the data output by the CPLD is converted into an analog voltage output. The storage module 4 is connected with the SPI pin of the CPLD, and the data output by the CPLD is stored. The level conversion circuit converts the external voltage adjustment signal into a first level signal conforming to the level isolation circuit, and then converts the first level signal into a second level signal conforming to the CPLD through the level isolation circuit. The second level signal is converted into an IIC signal (voltage adjustment digital signal) recognizable by the digital-to-analog conversion module 3 and the storage module 4 through the CPLD, so as to control the voltage output of the digital-to-analog conversion circuit and the storage, realize the functions of online adjustment and power-off storage.

[0035] The logic of the external control signal is shown in Table 1. The CPLD filters the received control signal (3 consecutive high, input high, 3 consecutive low, input low), and according to the input control signal, performs addition or subtraction operation on the input pulse, and transmits the obtained digital quantity to the analog-to-digital converter for voltage output. When receiving the storage command, the data is stored in the memory and the digital-to-analog converter. The data in the memory is convenient for adjusting the data again after power-on, and the data in the digital-to-analog converter is convenient for maintaining the voltage output after power-on. In Table 1, “↑” represents the conversion from low to high, “↓” represents the conversion from high to low, X represents irrelevant, L represents low, and H represents high.

[0036] Table 1: External control signal logic table

[0037] CS (chip select) UD (up / down control) INC (increment control) Description L L ↓ Decrement L H ↓ Increment L X ↑ No change H X X No change ↓ X X No change ↑ X L Position not stored ↑ X H Position stored

[0038] The adjusting level conversion isolation module 2, as shown in Figure 2 is composed of a voltage dividing resistor and a digital isolator, and realizes conversion of an input external voltage adjusting signal into a CPLD recognizable level signal. Specifically, the resistor R31 and the resistor R32 divide the voltage of the INC (Increment Control Input) of the external voltage adjusting signal, and then the voltage is input into the 3th pin of the U4 (digital isolator) through the current limiting resistor R25. The resistor R33 and the resistor R34 divide the voltage of the U / D (Up / Down Control Input) of the external voltage adjusting signal, and then the voltage is input into the 4th pin of the U4 through the current limiting resistor R26. The resistor R35 and the resistor R36 divide the voltage of the CS (Chip Select) of the external voltage adjusting signal, and then the voltage is input into the 5th pin of the U4 through the current limiting resistor R27. The left 1st pin of the U4 is connected with +5Visol, the 8th pin of the U4 is connected with GNDisol, the right 16th pin of the U4 is connected with +3V3D, the 9th pin of the U4 is connected with DGND, and the isolation level signals ISO_INC, ISO_U / D and ISO_CS output by the U4 are respectively connected to the general I / O pins F12, G13 and G15 of the U1A in the middle, so as to realize level signal isolation. Figure 5

[0039] As shown in Figure 3 , the digital-analog conversion module 3 is composed of a 15Bit digital-analog converter, and realizes linear conversion of data into 0-5V analog voltage output function. Specifically, one end of the first pull-up resistor R23 and one end of the second pull-up resistor R24 are respectively connected with the 1st pin and the 2nd pin of the U5 (15Bit digital-analog converter), and the other ends are connected to +3V3D. The SCLK and SDA of the U5 are respectively connected to the general I / O pins F14 and F16 of the U1A in the middle, the 4th pin of the U5 is connected to +12V, one end of the 1uF first capacitor C29 is connected to DGND, the other end is connected to the 8th pin of the U5, the 5th pin of the U5 is connected to DGND, and the 6th pin of the U5 is a voltage output end, and there is a 100nF second capacitor C30 between the voltage output end and DGND for filtering. Figure 5

[0040] The pulse amplitude discrimination in the nuclear instrument is to convert the input pulse signal with amplitude exceeding (or lower than) a certain level into an output pulse signal with amplitude meeting certain standards, and to eliminate any input pulse signal lower (or higher) than the level. Therefore, the reference voltage required by the pulse amplitude discrimination should cover the entire range of the pulse signal amplitude to be measured, and the reference voltage should be very stable, and the voltage adjusting linearity should be very good. The imported 10Bit digital potentiometer is used for adjusting and outputting the 5V reference voltage, and the voltage adjusting precision is low and the linearity is poor compared with the voltage output by the adjustable reference source control circuit of the present application.​​

[0041] As shown in the figure, the storage module 4 is realized by EEROM (Electrically Erasable Programmable Read-Only Memory). Figure 4 U3 (EEROM) is powered by 3.3V, and the SPI interface signals F_MCS_N, F_MCLK, F_MISO, F_MOSI of U3 are connected to the SPI interface of U1E respectively. Figure 4 As shown in the figure, the logic control module 1 is realized by CPLD, the SPI interface signals F_MCS_N, F_MCLK, F_MISO, F_MOSI of U3 are connected to the SPI interface of U1E respectively,

[0042] the SCLK and SDA of U5 are connected to the general I / O pins F14 and F16 of U1A respectively, Figure 5 the isolation level signals ISO_INC, ISO_U / D, ISO_CS output by U4 are connected to the general I / O pins F12, G13, G15 of U1A respectively. Figure 4 Figure 3 Compared with the related art, the application has the following advantages: Figure 2 The application provides a kind of adjustable reference source control circuit, and circuit structure is simple;The application uses domestic components, and compared with the imported digital potentiometer used now, supply cycle is short, saves product production time;The application provides a new circuit control thought, solves the problem of no domestic digital potentiometer available;The adjustable reference source control circuit of the application is 15Bit resolution, compared with the imported 10Bit digital potentiometer used now, effectively improves voltage regulation accuracy and regulation linearity.

[0043] The application provides a kind of adjustable reference source control circuit, and circuit structure is simple;The application uses domestic components, and compared with the imported digital potentiometer used now, supply cycle is short, saves product production time;The application provides a new circuit control thought, solves the problem of no domestic digital potentiometer available;The adjustable reference source control circuit of the application is 15Bit resolution, compared with the imported 10Bit digital potentiometer used now, effectively improves voltage regulation accuracy and regulation linearity.

[0044] The application provides a kind of adjustable reference source control circuit, and circuit structure is simple;The application uses domestic components, and compared with the imported digital potentiometer used now, supply cycle is short, saves product production time;The application provides a new circuit control thought, solves the problem of no domestic digital potentiometer available;The adjustable reference source control circuit of the application is 15Bit resolution, compared with the imported 10Bit digital potentiometer used now, effectively improves voltage regulation accuracy and regulation linearity.

[0045] The application provides a kind of adjustable reference source control circuit, and circuit structure is simple;The application uses domestic components, and compared with the imported digital potentiometer used now, supply cycle is short, saves product production time;The application provides a new circuit control thought, solves the problem of no domestic digital potentiometer available;The adjustable reference source control circuit of the application is 15Bit resolution, compared with the imported 10Bit digital potentiometer used now, effectively improves voltage regulation accuracy and regulation linearity.

[0046] The application provides a kind of adjustable reference source control circuit, and circuit structure is simple;The application uses domestic components, and compared with the imported digital potentiometer used now, supply cycle is short, saves product production time;The application provides a new circuit control thought, solves the problem of no domestic digital potentiometer available;The adjustable reference source control circuit of the application is 15Bit resolution, compared with the imported 10Bit digital potentiometer used now, effectively improves voltage regulation accuracy and regulation linearity.

[0047] The principles and implementation manners of the present application are described herein by using specific examples, and the above examples are only used to help understand the method of the present application and its core idea; meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation manners and application ranges will have changes. In conclusion, the content of the specification should not be understood as a limitation of the present application.

Claims

1. An adjustable reference source control circuit, characterized by The application relates to a voltage regulation conversion isolation module, and relates to the technical field of voltage regulation conversion isolation modules. The voltage regulation conversion isolation module comprises a level conversion circuit and a level isolation circuit connected in sequence. The level isolation circuit is connected with the logic processing module; the digital-analog conversion module is connected with the logic processing module; and the digital-analog conversion module comprises a 15Bit digital-analog converter. The level conversion circuit is used for converting an external voltage regulation signal into a first level signal. The level isolation circuit is used for converting the first level signal into a second level signal. The logic processing module is used for converting the second level signal into a voltage regulation digital signal. The digital-analog conversion module is used for converting the voltage regulation digital signal into a voltage regulation analog signal. The application further comprises a storage module connected with the logic processing module; and the storage module is used for storing the voltage regulation digital signal.

2. The adjustable reference source control circuit of claim 1, wherein, The storage module is an electrically erasable programmable read-only memory. The logic processing module is a complex programmable logic device.

3. The adjustable reference source control circuit of claim 1, wherein, The level conversion circuit comprises three voltage division units; each voltage division unit comprises a first voltage division resistor, a second voltage division resistor and a current limiting resistor connected in sequence; and the current limiting resistor is connected with the level isolation circuit.

4. The adjustable reference source control circuit of claim 1, wherein, The level isolation circuit is a digital isolator.

5. The adjustable reference source control circuit of claim 1, wherein, The digital-analog conversion module further comprises a first pull-up resistor, a second pull-up resistor, a first capacitor and a second capacitor; one end of the first pull-up resistor, one end of the second pull-up resistor, one end of the first capacitor and one end of the second capacitor are all connected with the 15Bit digital-analog converter; the other end of the first pull-up resistor and the other end of the second pull-up resistor are both connected with a power supply; and the other end of the first capacitor and the other end of the second capacitor are both grounded.

6. The adjustable reference source control circuit of claim 1, wherein, ​ 7. The adjustable reference source control circuit of claim 1, wherein, ​

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