CN204166138U - Based on the Multi channel spectrum analysis instrument of ADS1605 - Google Patents

Abstract

The utility model discloses a multi-channel energy spectrum analyzer based on ADS1605, which comprises two parts: the first part is a front-end conditioning circuit composed of a front-end amplifier circuit, a linear amplifier circuit, a filter shaping circuit and a differential conversion circuit, and the analog input signal After the front-end conditioning circuit signal is amplified, it is differentially converted and the differential signal is output; the second part is the control circuit, including the differential signal of the first part and the input signal drive of the voltage reference circuit, as well as the external clock control circuit and working state control circuit to control ADS1605 data acquisition . The utility model introduces the newly developed high-speed ARM7 processor into the multi-channel energy spectrum analyzer. Through the front-end conditioning circuit and the control circuit, the signal differential conversion and amplification, the working state control, and the shaping of the acquisition signal are carried out to realize the high-speed and high-speed operation of the ADS1605. Precision 16-bit 5MHZ analog-to-digital conversion.

Description

Multi-channel Energy Spectrum Analyzer Based on ADS1605

technical field

The utility model belongs to the technical field of nuclear energy spectrum measurement and relates to a multi-channel energy spectrum analyzer based on ADS1605.

Background technique

Nuclear energy spectrum measurement technology is a highly comprehensive emerging technology, which integrates multiple disciplines such as electronic technology, nuclear detection technology, and computer technology. At present, it has become one of the important means of material composition analysis, and plays an increasingly important role in medicine, geology, environmental science, chemistry, archaeology and other disciplines.

With the rapid development of nuclear electronics and computer technology, the performance of multi-channel energy spectrum analyzers has been continuously improved. Foreign nuclear spectrometers have high performance, but are expensive and difficult to be widely used by most domestic users. After several years of hard work, domestic researchers have developed multi-channel energy spectrometers constructed from early traditional analog circuits and digital circuits. So far, various types of energy spectrometers for field (on-site) use have been developed. At present, multi-channel energy spectrometers are developing toward the trend of powerful functions, stable performance, high instrument integration, easy-to-use operating environment, and low power consumption.

As a key component of the multi-channel energy spectrum analyzer, it mainly completes the following main tasks: (1) Differentially amplifies the input charge level signal and ensures that the signal is not distorted during the amplification process; (2) Forming a circuit through filtering can The input signal composed of external noise, system noise and useful signal superposition is denoised; (3) In order to preprocess the original data and obtain better measurement results, it is necessary to have a faster acquisition speed and measurement accuracy.

Utility model content

The purpose of this utility model is to provide a multi-channel energy spectrum analyzer based on ADS1605 that can meet the requirements of the hardware system in the nuclear energy spectrum analyzer system for data analog-to-digital conversion.

Technical scheme of the utility model:

A multi-channel energy spectrum analyzer based on ADS1605, which includes two parts, a front-end conditioning circuit and a control circuit, the front-end conditioning circuit includes a front-end amplifier circuit U1, a linear amplifier circuit U2, a filter shaping circuit U3 and a differential conversion circuit U4; the control circuit Including voltage reference circuit U5, working state control circuit U6 and clock control circuit U7; differential conversion circuit U4, voltage reference circuit U5, working state control circuit U6 and clock control circuit U7 are connected with ADS1605 analog-to-digital converter U8; the input charge signal is passed through The front-end amplifier circuit U1 is amplified at the first level, and then after the main amplification of the linear amplifier circuit U2, it is filtered by U3 and converted by U4 to form a differential input signal that is connected to pins 4 and 5 of the ADS1605 analog-to-digital converter U8; in the voltage reference circuit U5 The input voltage is passed through the precision reference voltage source chip and then the reference voltage is output through differential conversion, which is connected to the pins 60, 61, 62, 63, 64 of ADS1605 analog-to-digital converter U8, and ADS1605 analog-to-digital converter U8 converts the differentially converted input The signal is compared with the reference voltage after differential conversion to quantify the data; the external voltage input in the working state control circuit U6 is connected to the working control bit pins 13, 15, 21, 22 of the ADS1605 analog-to-digital converter U8 through the dial switch, Control the working state of the ADS1605 analog-to-digital converter U8; finally, in the clock control circuit U7, an external clock oscillator is connected to the pin 56 of the ADS1605 analog-to-digital converter U8 to provide a stable clock signal to the ADS1605 to control the data sampling of the ΔΣ modulator.

After the analog input signal is connected to the circuit, it passes through two independent amplifying circuits in series to realize the first-level amplification and second-level amplification of the signal, and then connects to the filter shaping circuit, which is output by the differential conversion circuit, and the clock signal is input through the external clock input circuit and works The control circuit hardware controls the ADS1605 chip selection bit and the read/write bit high and low levels, and adopts a differential input method to realize the parallel acquisition of 16-bit 5MHZ high-speed and high-precision signals.

The core component of the front-end amplifier circuit U1 is the LF357 operational amplifier. The analog signal input is connected to the 2nd pin of the LF357 operational amplifier through a capacitor; a capacitor and a resistor are connected in parallel and connected across the 2nd pin terminal and the 6th pin of the LF357 operational amplifier. The terminal of the output pin is connected to the input end of the linear amplifier circuit U2 via the No. 6 output of the front-end amplifier circuit U1.

In the linear amplification circuit U2, the signal output from the front-end amplification circuit U1 of the upper stage circuit is connected to the No. 2 pin of the NE5534 operational amplifier through a resistor, and a capacitor and a resistor are connected in parallel and then connected across the No. 2 pin of the NE5534 operational amplifier and Between No. 6 pins; two capacitors are connected in parallel to the positive and negative power supply pins of the NE5534 operational amplifier, and are output by No. 6 of the NE5534 operational amplifier.

In the voltage reference circuit U5, the input voltage is connected to the No. 2 pin of the REF028U reference chip through a filter circuit composed of four capacitors with different capacitances. After filtering, the signal output from the pin 6 is divided into four outputs: two of them The circuit is converted by two OPA2822U operational amplifiers U9 and U10 to form a voltage reference signal. The two circuits are connected as follows: one signal is connected to the pin 5 of the OPA2822U operational amplifier U9 through the potentiometer, and the secondary output pin of the OPA2822U operational amplifier U9 No. 7 is connected to the reference voltage negative pins 60 and 61 of the ADS1605 analog-to-digital converter U8; one signal is connected to the pin 3 of the OPA2822U operational amplifier U10 through the potentiometer, and the primary output pin No. 1 of U10 is connected to the ADS1605 module The positive pins 63 and 64 of the reference voltage of the digital converter U8; the other two connections are as follows: one signal is connected to the pin 3 of the OPA2822U operational amplifier U9, and the first-stage output pin 1 of the OPA2822U operational amplifier U9 is connected to the ADS1605 module The voltage median pin 62 of the digital converter U8, and the signal output from pin 1 is divided into two routes and connected to pin 6 of the OPA2822U operational amplifier U9 and pin 2 of the OPA2822U operational amplifier U10; the other signal is connected to the OPA2822U operational amplifier The pin 5 of the amplifier U10 is provided to the VCM of the differential conversion circuit through the secondary output pin 7 of the OPA2822U operational amplifier U10 for data quantization comparison.

In the working state control circuit U6, the four-way exclusion is connected to the working control bit pins 13, 15, 21, 22 of the ADS1605 analog-to-digital converter U8 through the DIP switch; in the external clock control circuit U7, the clock oscillator XOSM -573 pin 3 is connected to ADS1605 Analog to Digital Converter U8 pin 56.

The device is preferably: analog-to-digital converter ADS1605, front-end amplifier LF357 is provided in the front-end amplifier circuit, amplifier NE5534 is selected for the linear amplifier circuit, amplifier OPA2822U is selected for the differential conversion circuit, voltage reference chip REF028U, and external clock oscillator XOSM-573.

The utility model is composed of multi-channel energy spectrum analyzer hardware based on ADS1605. In order to improve the acquisition speed and stability of the analog-to-digital converter ADS1605, the input signal after differential conversion is compared with the reference voltage after differential conversion to quantify the data. , while the external clock input clock signal and hardware control working status. It also adopts 16-bit parallel acquisition method, and the acquisition rate can reach 5MHZ, so that the utility model can realize high-speed acquisition and high-precision measurement while adapting to the reduction of volume and enhancing the human-computer interaction ability; the digital filtering algorithm is used to preprocess the data, The data reliability of the device and the performance of the whole system are improved; at the same time, when the sampling is stopped, the power consumption of the system is reduced by starting the sleep mode.

The utility model combines the characteristics and advantages of the nuclear energy spectrum analysis technology and data acquisition technology, analyzes and demonstrates the existing instruments, and introduces a 16-bit 5MHZ high-speed high-precision analog-to-digital converter into the multi-channel energy spectrum analyzer for the first time, and the application is independent The developed ARM7 core board controls the collection and transmission of data. Through appropriate modification of the real-time measurement of the front-end conditioning circuit and filter circuit, the ARM digital filter function is added, and the human-computer interaction software is reasonably designed to improve system performance.

Description of drawings

Fig. 1 is the structural representation in the utility model embodiment;

Fig. 2 is a schematic diagram of the front-end conditioning circuit in the embodiment of the present invention.

Fig. 3 is a schematic diagram of the control circuit in the embodiment of the utility model.

Detailed ways

The utility model can be specifically implemented through the above-mentioned utility model technical scheme, and is further illustrated by the following technical experiment report and examples. However, the scope of the utility model is not limited to the following examples.

Example 1:

A multi-channel energy spectrum analyzer based on ADS1605, which includes two parts, a front-end conditioning circuit and a control circuit, the front-end conditioning circuit includes a front-end amplifier circuit U1, a linear amplifier circuit U2, a filter shaping circuit U3 and a differential conversion circuit U4; the control circuit Including voltage reference circuit U5, working state control circuit U6 and clock control circuit U7; differential conversion circuit U4, voltage reference circuit U5, working state control circuit U6 and clock control circuit U7 are connected with ADS1605 analog-to-digital converter U8; the input charge signal is passed through The front-end amplifier circuit U1, linear amplifier circuit U2, filter shaping circuit U3 and differential conversion circuit U4 are connected to the pins 4 and 5 of the ADS1605 analog-to-digital converter U8; the input voltage in the voltage reference circuit U5 is connected to the REF028U reference chip U11, and the output The voltage is connected to the pins 60, 61, 62, 63, and 64 of the ADS1605 analog-to-digital converter U8 through two OPA2822U operational amplifiers U9 and U10; at the same time, the secondary output pin 7 of the OPA2822U operational amplifier U10 is connected to the VCM of the differential conversion circuit U4 terminal connection; the working state control circuit U6 is connected to the four-way exclusion through the DIP switch and connected to the working control bit pins 13, 15, 21, and 22 of the ADS1605 analog-to-digital converter U8 through pins 5, 6, 7, and 8, respectively. ; The clock oscillator XOSM-573 pin 3 in the external clock control circuit U7 is connected to the ADS1605 analog-to-digital converter U8 pin 56.

The core component of the front-end amplifier circuit U1 is the LF357 operational amplifier. The analog signal input is connected to the 2nd pin of the LF357 operational amplifier through a capacitor; a capacitor and a resistor are connected in parallel and connected across the 2nd pin terminal and the 6th pin of the LF357 operational amplifier. At the end of the output pin, the No. 6 output pin of the LF357 operational amplifier is connected to a capacitor and connected to the input end of the next circuit module, that is, connected in series to the input end of the linear amplifier circuit U2.

In the linear amplification circuit U2, the signal output from the front-end amplification circuit U1 of the upper stage circuit is connected to the No. 2 pin of the NE5534 operational amplifier through a resistor, and a capacitor and a resistor are connected in parallel and then connected across the No. 2 pin of the NE5534 operational amplifier and Between No. 6 pins; two capacitors are connected in parallel to the positive and negative power supply pins of the NE5534 operational amplifier, and the No. 6 output pin of the NE5534 operational amplifier is connected to the input terminal of the next-stage circuit with the capacitor.

In the voltage reference circuit U5, the input voltage passes through a filter circuit composed of four capacitors with different capacitances, and is connected to the No. 2 pin of the REF028U reference chip, and then output through pin 6 and then filtered by parallel capacitors, and then divided into four outputs; The two circuits are converted by two OPA2822U operational amplifiers U9 and U10 to form a voltage reference signal. The two circuits are connected as follows: one signal is connected to pin 5 of the OPA2822U operational amplifier U9 through a potentiometer, and the secondary output pin of the OPA2822U operational amplifier U9 Pin 7 is connected to the reference voltage negative pins 60 and 61 of the ADS1605 analog-to-digital converter U8; one signal is connected to the pin 3 of the OPA2822U operational amplifier U10 through the potentiometer, and the primary output pin 1 of the OPA2822U operational amplifier U10 Connect to the positive stage pins 63 and 64 of the reference voltage of U8; the other two connections are as follows: one signal is connected to the pin 3 of the OPA2822U operational amplifier U9, and is connected to the voltage of U8 through the primary output pin 1 of the OPA2822U operational amplifier U9 The median pin 62, while the signal output from pin 1 is connected to pin 6 of OPA2822U operational amplifier U9 and pin 2 of OPA2822U operational amplifier U10 in two ways; the other signal is connected to pin 5 of OPA2822U operational amplifier U10 , and the secondary output pin 7 of the OPA2822U operational amplifier U10 is connected to the VCM end of the differential conversion circuit U4.

Further explanation in conjunction with accompanying drawings:

In Figure 1, the input charge signal is amplified by the front-end amplifier circuit U1, and the signal input after the first-stage amplification is then amplified by the linear amplifier circuit U2, and the signal after the two-stage amplification is composed of external noise, system noise and useful signal Composed of superimposition, the signal is denoised by the filter forming circuit U3, and the processed signal is input to the differential input circuit U4 to form a differential mode signal, which is connected to the 16-bit analog-to-digital converter ADS1605U8 through the filter circuit; the voltage reference circuit U5 , the input voltage is passed through the precision reference voltage source chip, and then the reference voltage is output through differential conversion, which is connected to U8, so that ADS1605 compares the input signal after differential conversion with the reference voltage after differential conversion to quantify the data; at the same time, the working state control circuit In U6, through the external voltage input, it is connected to the working control bit of U8 through the dial switch to control the working state of U8; finally, in the external clock control circuit U7, the external clock oscillator is connected to U8 to provide a stable clock signal for ADS1605 to control ΔΣ modulation The data sampling of the device.

The front-end conditioning circuit is shown in Figure 2. The core component of the front-end amplifier circuit is an LF357 operational amplifier, and the analog signal input is connected to the No. 2 pin of U9 through a capacitor. A capacitor and a resistor are connected in parallel and connected across pin 2 and output pin 6 of the LF357 operational amplifier. The output pin 6 of the LF357 operational amplifier is connected to the capacitor for overvoltage protection and connected to the next circuit module. The input terminal is the input terminal of the linear amplifier circuit. In the linear amplification circuit, the signal output from the front-end amplification circuit of the upper stage circuit is connected to the 2nd pin of the NE5534 operational amplifier through a resistor, and the capacitor C4 and the resistor R3 are connected in parallel and connected across the 2nd pin and the 6th pin of the NE5534 operational amplifier between pins. The two capacitors are connected in parallel to the positive and negative power supply pins of the NE5534 operational amplifier to filter the signal. The No. 6 output pin of the NE5534 operational amplifier is connected to the capacitor for overvoltage protection and connected to the input of the next stage circuit. end.

The control circuit is shown in Figure 3. In the voltage reference circuit U5, the input voltage passes through a filter circuit composed of four capacitors with different capacitances, and is connected to the No. 2 pin of the REF028U reference chip U11, and the stable voltage output through the pin 6 is filtered by parallel capacitors, and then divided into four circuits output. Two of them are converted by two OPA2822U operational amplifiers U9 and U10 to form a voltage reference signal. The two circuits are connected as follows: one signal is connected to pin 5 of OPA2822U operational amplifier U9 through a potentiometer, and the secondary output of OPA2822U operational amplifier U9 Pin No. 7 is connected to the reference voltage negative pins 60 and 61 of the ADS1605 analog-to-digital converter U8; one signal is connected to the pin 3 of the OPA2822U operational amplifier U10 through the potentiometer, and the primary output pin 1 of the OPA2822U operational amplifier U10 No. is connected to the reference voltage positive stage pins 63, 64 of U8. The other two connections are as follows: one signal is connected to pin 3 of OPA2822U operational amplifier U9, and the primary output pin 1 of OPA2822U operational amplifier U9 is connected to the voltage median pin 62 of U8, and the signal output from pin 1 Connect to pin 6 of OPA2822U operational amplifier U9 and pin 2 of OPA2822U operational amplifier U10 in two ways; the other signal is connected to pin 5 of OPA2822U operational amplifier U10 and provided by the secondary output pin 7 of OPA2822U operational amplifier U10 The VCM of the differential conversion circuit is used for data quantization comparison. In the working state control circuit U6, the four-way exclusion is connected to the working control bit pins 13, 15, 21, 22 of U8 through the dip switch. In the external clock control circuit U7, the clock oscillator XOSM-573 pin 3 is connected to U8 pin 56. the

This program uses the ADS1605 analog-to-digital conversion chip U8, which is a 16-bit, bipolar differential input channel, with the fastest acquisition rate of 5MSPS, low noise, low bias, low temperature drift, and low power consumption. The analog-to-digital conversion of a multi-channel energy spectrum analyzer is ideal.

Claims (5)

1. based on a Multi channel spectrum analysis instrument of ADS1605, it comprises two parts, and front end modulate circuit and control circuit, is characterized in that:

Front end modulate circuit comprises frontend amplifying circuit U1, linear amplifier circuit U2, filtering shaping circuit U 3 and differential conversion circuit U4;

Control circuit comprises voltage reference circuit U5, working state controlling circuit U6 and clock control circuit U7;

Differential conversion circuit U4, voltage reference circuit U5, working state controlling circuit U6 are connected with ADS1605 analog to digital converter U8 with clock control circuit U7;

Input charge signal amplifies through frontend amplifying circuit U1 one-level, then after the main amplification of linear amplifying circuit U2, by U3 filtering, forms differential input signal be connected on the pin 4,5 of ADS1605 analog to digital converter U8 through U4 conversion; In voltage reference circuit U5, input voltage is after accurate reference voltage chip, input signal after differential conversion and the reference voltage after differential conversion are made comparisons and are carried out data quantification by pin 60,61,62,63,64, the ADS1605 analog to digital converter U8 being connected to ADS1605 analog to digital converter U8 by differential conversion output reference voltage again; The input of working state controlling circuit U6 peripheral voltage is connected to job control position pin 13,15,21,22, the control ADS1605 analog to digital converter U8 duty of ADS1605 analog to digital converter U8 through toggle switch; In last clock control circuit U7, be connected to the pin 56 of ADS1605 analog to digital converter U8 by external clock oscillator, provide stable clock signal to control the data sampling of Deltasigma modulator to ADS1605.

2. the Multi channel spectrum analysis instrument based on ADS1605 according to claim 1, is characterized in that: the core parts of frontend amplifying circuit U1 are LF357 operational amplifier U11, and simulating signal input is connected to No. 2 pins of LF357 operational amplifier by electric capacity; No. 2 pin end points and No. 6 output pin end points places of LF357 operational amplifier are connected across after an electric capacity and a resistor coupled in parallel, through No. 6 outputs, the input end of connecting linear amplifying circuit U2.

3. the Multi channel spectrum analysis instrument based on ADS1605 according to claim 1, it is characterized in that: in linear amplifier circuit U2, the signal exported from upper level circuit front-end amplifying circuit U1 to receive No. 2 pins of NE5534 operational amplifier U12 by resistance, be connected across between No. 2 pins of NE5534 operational amplifier and No. 6 pins after an electric capacity and a resistor coupled in parallel; Be connected on the positive-negative power end pin of NE5534 operational amplifier after two Capacitance parallel connections, by No. 6 outputs of NE5534 operational amplifier.

4. the Multi channel spectrum analysis instrument based on ADS1605 according to claim 1, it is characterized in that: in voltage reference circuit U5, input voltage is through the filtering circuit of the different electric capacity composition of four capacitances, receive No. 2 pins of REF028U fiducial chip, the signal exported by pin 6 is after filtering, four tunnels are divided to export: wherein two-way is by two OPA2822U operational amplifier U9, U10 changes, coating-forming voltage reference signal, this two-way connects as follows: a road signal is connected to the pin 5 of OPA2822U operational amplifier U9 by potentiometer, the reference voltage that No. 7, the secondary output pin of OPA2822U operational amplifier U9 is connected to ADS1605 analog to digital converter U8 bears level pin 60, 61, one road signal is connected to the pin 3, U10 of OPA2822U operational amplifier U10 No. 1, one-level output pin by potentiometer is connected to the positive level pin 63,64 of reference voltage of ADS1605 analog to digital converter U8, another two-way connects as follows: a road signal is connected to the pin 3 of OPA2822U operational amplifier U9, one-level output pin 1 through OPA2822U operational amplifier U9 is connected to the voltage intermediate value pin 62 of ADS1605 analog to digital converter U8, the pin 2 of the pin 6 that the signal simultaneously exported from pin 1 divides two-way to be connected to OPA2822U operational amplifier U9 and OPA2822U operational amplifier U10, another road signal is connected to the pin 5 of OPA2822U operational amplifier U10, and the VCM that the secondary output pin 7 through OPA2822U operational amplifier U10 is supplied to differential conversion circuit makes data and quantizes to compare.

5. the Multi channel spectrum analysis instrument based on ADS1605 according to claim 1, it is characterized in that: in working state controlling circuit U6, be connected to the job control position pin 13,15,21,22 of ADS1605 analog to digital converter U8 by toggle switch Pang Jie tetra-road exclusion; In external clock control circuit U7, clock oscillator XOSM-573 pin 3 is connected to ADS1605 analog to digital converter U8 pin 56.