CN112769434A - High-precision DAC test system based on FPGA - Google Patents

Abstract

The invention discloses a high-precision DAC testing system based on FPGA, which belongs to the field of semiconductor chip testing. An FPGA-based high-precision DAC test system, including an FPGA development board, a power supply, a DAC test board, a spectrum analyzer, an oscilloscope, and a digital multimeter; the power supply is connected to the FPGA development board and the DAC test board to provide stable voltage; the FPGA development board sends parallel digital signals and clock signals to the DAC test board, and the DAC test board converts the digital signal into an analog output; the DAC test board is connected to the spectrum analyzer, the The oscilloscope is connected to the digital multimeter for analyzing the output analog quantity. The invention adopts the design technology of FPGA, can complete the static parameter test and dynamic parameter test of the digital-to-analog converter, improves the test efficiency of the digital-to-analog converter, can expand the test function according to actual test requirements, and has lower test cost.

Description

A High Precision DAC Test System Based on FPGA

technical field

The invention relates to the technical field of semiconductor chip testing, in particular to an FPGA-based high-precision DAC testing system.

Background technique

In recent years, with the rapid development of integrated circuits, digital signal processing technology has been widely used. Compared with analog signals, digital signal processing has many advantages, for example, the performance of digital systems is less sensitive to changes in voltage, process, temperature, etc.; digital circuits are easy to automate design, making it possible to realize complex systems; digital systems have Good programmability, so the functions of the system can be flexible and diverse; digital signals are easy to store and transmit; in addition, with the development of CMOS manufacturing processes, the speed of digital circuits will become faster and the power consumption will be lower. However, almost all physical signals from nature are analog signals, such as temperature, speech, images, and so on. In a typical signal processing system, the digital signal processing part is often at the core of the system and completes most of the signal calculation processing. The analog part is at the periphery of the system, and the ADC and DAC play a key role as a bridge between the analog signal and the digital signal. With the rapid development of integrated circuits, DACs are also widely used, especially high-speed and high-precision DACs are widely demanded in electronic products. At the same time, stricter requirements are put forward for the test progress, test methods and test conditions of DAC technology.

In large-scale semiconductor chip production, automatic test equipment (ATE) is generally used for chip testing. ATE is a set of high-performance test equipment controlled by a computer. For DAC, the digital waveform generator of ATE is mainly used to provide input signals, and built-in The ADC captures the analog output of the DAC under test and calculates and evaluates it. However, due to the complex structure of the system, the cost of high-precision ATE is quite high, and with the improvement of semiconductor technology and design level, the chip performance is also continuously improved, and the ATE used to test these chips also needs higher precision. To meet the testing needs, this will further increase the chip cost.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a high-precision DAC test system based on FPGA, which can complete the static and dynamic parameter test of the digital-to-analog converter, improve the test efficiency of the digital-to-analog converter, and can expand the function according to the test requirements, and is very convenient. Minimize the cost of testing.

In order to solve the above technical problems, the present invention provides a high-precision DAC test system based on FPGA, including an FPGA development board, a power supply, a DAC test board, a spectrum analyzer, an oscilloscope and a digital multimeter;

The power supply is connected to the FPGA development board and the DAC test board to provide a stable voltage; the FPGA development board sends parallel digital signals and clock signals to the DAC test board, and the DAC test board sends the digital signal to the DAC test board. The signal is converted into an analog output;

The DAC test board is respectively connected with the spectrum analyzer, the oscilloscope and the digital multimeter for analyzing the output analog quantity.

Optionally, the FPGA development board includes a main controller module FPGA chip, a regulated power supply module, a RAM memory module, a FLASH memory module, an active crystal oscillator module and a JTAG interface module;

The regulated power supply module is respectively connected with the main controller module FPGA chip, the RAM memory module, the FLASH memory module, the active crystal oscillator module and the JTAG interface module;

The main controller module FPGA chip is respectively connected with the RAM memory module, the FLASH memory module, the active crystal oscillator module and the JTAG interface module.

Optionally, the main controller module FPGA chip includes a digital signal generator, an embedded memory and a high-speed I/O port; wherein,

The signal generator includes a frequency register, a phase register, a sinusoidal ROM look-up table and a D/A converter connected in sequence.

Optionally, the active crystal oscillator module is a 50MHz high-precision active crystal oscillator module.

The invention provides an FPGA-based high-precision DAC test system, including an FPGA development board, a power supply, a DAC test board, a spectrum analyzer, an oscilloscope and a digital multimeter; the power supply, the FPGA development board and the DAC test board connected to provide a stable voltage; the FPGA development board sends a parallel digital signal and a clock signal to the DAC test board, and the DAC test board converts the digital signal into an analog output; the DAC test board and the The spectrum analyzer, the oscilloscope and the digital multimeter are connected to analyze the output analog quantity. The invention adopts the design technology of FPGA, can complete the static parameter test and dynamic parameter test of the digital-to-analog converter, improves the test efficiency of the digital-to-analog converter, and can expand the test function according to actual test requirements, and has lower test cost.

Description of drawings

Fig. 1 is the structural block diagram of the high-precision DAC test system based on FPGA provided by the present invention;

Fig. 2 is the structural block diagram of the FPGA development board in the FPGA-based high-precision DAC test system;

Fig. 3 is the structural block diagram of the signal generator in the FPGA chip of the main controller module.

Detailed ways

A FPGA-based high-precision DAC test system proposed by the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become apparent from the following description and claims. It should be noted that the accompanying drawings are all in a very simplified form and in inaccurate scales, and are only used to facilitate and clearly assist the purpose of explaining the embodiments of the present invention.

Example 1

The present invention provides an FPGA-based high-precision DAC test system, the structure of which is shown in Figure 1, including an FPGA development board, a power supply, a DAC test board, a spectrum analyzer, an oscilloscope and a digital multimeter; the power supply and the FPGA The development board is connected to the DAC test board to provide a stable voltage; the FPGA development board sends a parallel digital signal and a clock signal to the DAC test board, and the DAC test board converts the digital signal into an analog output; The DAC test board is respectively connected with the spectrum analyzer, the oscilloscope and the digital multimeter for analyzing the output analog quantity.

As shown in Figure 2, the FPGA development board includes a main controller module FPGA chip, a regulated power supply module, a RAM memory module, a FLASH memory module, an active crystal oscillator module and a JTAG interface module. The active crystal oscillator module is a 50MHz high-precision active crystal oscillator module. The regulated power supply module is respectively connected with the main controller module FPGA chip, the RAM memory module, the FLASH memory module, the active crystal oscillator module and the JTAG interface module; the main controller module FPGA chip is respectively connected with the RAM memory module and the FLASH memory module. , The active crystal oscillator module is connected with the JTAG interface module.

The main controller module FPGA chip includes a digital signal generator, an embedded memory and a high-speed I/O port; wherein, as shown in Figure 3, the signal generator includes a frequency register, a phase register, and a sinusoidal ROM search that are connected in sequence. table and D/A converter.

The working principle of the present invention is as follows: when the FPGA-based high-precision DAC test system provided by the present invention works, the power supply provides stable voltage for each part of the test system, and the FPGA development board sends parallel digital input signals to the DAC test board, and the DAC tests The board converts the digital waveforms to analog outputs, which are then passed to the analyzer for analysis. The digital multimeter measures the DAC static parameters, the oscilloscope measures the time domain waveform of the DAC dynamic parameters, and the spectrum analyzer measures the frequency domain characteristics of the DAC dynamic parameters.

FIG. 2 is a circuit block diagram of an FPGA development board in the FPGA-based high-precision DAC test system of the present invention. The model of the FPGA development board used in this test system is H3C40-V6, which includes: the main controller module FPGA chip, the regulated power supply module that provides stable voltage for the FPGA development board, the RAM memory module that facilitates data storage, A high-speed FLASH memory module for configuration file storage, a 50MHz high-precision active crystal oscillator module that provides a stable clock for the FPGA, and a JTAG download port for downloading compiled data and a low-jitter clock generator. The core device of the FPGA development board, the main controller module, the FPGA chip, whose model is EP3C40484C6N, is used to control the work of each module, and complete the test excitation control and test data acquisition of the device under test according to the settings.

3 is a circuit block diagram of a digital signal generator in the FPGA-based high-precision DAC test system of the present invention. After sampling, the ideal sinusoidal digital signal is converted into a frequency control word (FCW), which is input to the frequency register and then transferred to the phase register for accumulation to obtain the corresponding phase value. The sinusoidal ROM look-up table uses the high N bits output by the phase register as its input address. The digital code output by the sinusoidal ROM look-up table is input into the DAC converter and converted into an analog signal.

FPGA is a field programmable gate array, which has the advantages of good flexibility, short design cycle, wide application range and low cost, which greatly reduces the research and development cost and design difficulty of chip design, and has a wide range of applications. Compared with the traditional test method, the FPGA-based high-precision DAC test system can greatly reduce the design cost and cycle while ensuring the DAC test function and accuracy.

The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes and modifications made by those of ordinary skill in the field of the present invention based on the above disclosure all belong to the protection scope of the claims.

Claims (4)

1. A high-precision DAC test system based on an FPGA is characterized by comprising an FPGA development board, a power supply, a DAC test board, a spectrum analyzer, an oscilloscope and a digital multimeter;

the power supply is connected with the FPGA development board and the DAC test board and provides stable voltage for the FPGA development board and the DAC test board; the FPGA development board sends parallel digital signals and clock signals to the DAC test board, and the DAC test board converts the digital signals into analog quantity to be output;

and the DAC test board is respectively connected with the spectrum analyzer, the oscilloscope and the digital multimeter and is used for analyzing the output analog quantity.

2. The FPGA-based high-precision DAC testing system of claim 1, wherein the FPGA development board comprises a main controller module FPGA chip, a regulated power supply module, a RAM memory module, a FLASH memory module, an active crystal oscillator module and a JTAG interface module;

the stabilized voltage supply module is respectively connected with the FPGA chip, the RAM memory module, the FLASH memory module, the active crystal oscillator module and the JTAG interface module of the main controller module;

the FPGA chip of the main controller module is respectively connected with the RAM memory module, the FLASH memory module, the active crystal oscillator module and the JTAG interface module.

3. The FPGA-based high-precision DAC testing system of claim 2 wherein the main controller module FPGA chip comprises a digital signal generator, an embedded memory and a high-speed I/O port; wherein,

the signal generator comprises a frequency register, a phase register, a sine ROM lookup table and a D/A converter which are connected in sequence.

4. The FPGA-based high-precision DAC testing system of claim 2 wherein the active crystal oscillator module is a 50MHz high-precision active crystal oscillator module.

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