Board card DC calibration device and analog-to-digital hybrid board card

Abstract

The utility model relates to a board card DC calibration device and an analog-to-digital hybrid board card, the device comprises a differential-to-single-ended module, a gain adjustment module and a single-ended-to-differential module which are arranged in the board card and are connected in sequence, and the differential-to-single-ended module is connected with a function module in the board card, receives an output signal of the function module and outputs the output signal to the single-ended-to-differential module; outputting a single-ended signal to the gain adjustment module; the gain adjustment module performs gain adjustment on the received single-ended signal and outputs the adjusted single-ended signal to the single-ended to differential module; and the single-ended to differential module converts the adjusted single-ended signal into a differential signal, then performs signal acquisition, and outputs acquisition data for calibrating the functional module. External devices needing to be connected for board card calibration can be reduced, parallel calibration of multiple board cards is supported, and the calibration efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of semiconductor testing technology, and in particular to a board DC calibration device and a mixed analog-to-digital board. Background Technology

[0002] Semiconductor automated testing refers to the use of automated test equipment (ATE) to inspect various parameters of chips, eliminating defective products and controlling the quality of semiconductors before they leave the factory. In traditional mixed-signal board DC calibration and verification, the output calibration and verification of the device under test (DUT) typically uses an external high-precision multimeter for direct measurement. The calibration and verification effect is confirmed by comparing the output value of the DUT with the value acquired by the multimeter. Input calibration and verification uses a high-precision DAC (digital-to-analog converter) to simultaneously output signals to both the DUT and the multimeter. The calibration and verification effect is confirmed by comparing the input value of the DUT with the value acquired by the multimeter. Because this requires external connections to both the multimeter and the high-precision DAC, it is not convenient for parallel calibration of multiple boards, resulting in low calibration efficiency. Utility Model Content

[0003] Therefore, it is necessary to provide a board-based DC calibration device and a hybrid analog-to-digital board that can improve calibration efficiency to address the above problems.

[0004] The first aspect of this application provides a board-based DC calibration device, comprising a differential-to-single-ended module, a gain adjustment module, and a single-ended-to-differential module disposed within the board and connected in sequence, wherein:

[0005] The differential-to-single-ended module is connected to the functional module in the board, receives the output signal of the functional module, and outputs a single-ended signal to the gain adjustment module.

[0006] The gain adjustment module adjusts the gain of the received single-ended signal and outputs the adjusted single-ended signal to the single-ended to differential module.

[0007] The single-ended to differential module converts the adjusted single-ended signal into a differential signal for signal acquisition and outputs the acquired data for calibrating the functional module.

[0008] In one embodiment, the device further includes a link switching module disposed within a board, the link switching module being connected to the differential-to-single-ended module, the functional module, and a ground terminal; the link switching module is used to connect the input port of the differential-to-single-ended module to the functional module or the ground terminal, so that the input port of the differential-to-single-ended module receives the differential signal or single-ended signal output by the functional module.

[0009] In one embodiment, the differential-to-single-ended module includes operational amplifier U1, operational amplifier U2, operational amplifier U3, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7 and resistor R8.

[0010] The inverting input terminal of the operational amplifier U1 is connected to the first terminal of the resistor R1 and the first terminal of the resistor R3. The non-inverting input terminal of the operational amplifier U1 is connected to the link switching module. The output terminal of the operational amplifier U1 is connected to the second terminal of the resistor R3 and the first terminal of the resistor R5. The second terminal of the resistor R5 is connected to the inverting input terminal of the operational amplifier U3.

[0011] The second end of resistor R1 is connected to the first end of resistor R2. The second end of resistor R2 is connected to the inverting input of operational amplifier U2. The inverting input of operational amplifier U2 is connected to the first end of resistor R4. The non-inverting input of operational amplifier U2 is connected to the link switching module. The output of operational amplifier U2 is connected to the second end of resistor R4 and the first end of resistor R6. The second end of resistor R6 is connected to the non-inverting input of operational amplifier U3 and the first end of resistor R8. The second end of resistor R8 is grounded.

[0012] The inverting input terminal of the operational amplifier U3 is connected to the first terminal of the resistor R7, and the output terminal of the operational amplifier U3 is connected to the second terminal of the resistor R7 and the gain adjustment module.

[0013] In one embodiment, the gain adjustment module has two or more gain levels. It adjusts the gain of the received single-ended signal according to different gain levels and outputs the adjusted single-ended signal to the single-ended to differential module. The single-ended to differential module converts the received single-ended signal into a differential signal and then performs signal acquisition, outputting the acquisition data corresponding to different gain levels for use in calibrating the functional module.

[0014] In one embodiment, the gain adjustment module includes an operational amplifier U4, resistors R9, R10, R11, R12, and R13, switches K5, K6, K7, and K8, and a capacitor C1.

[0015] The first end of resistor R9 is connected to the first end of switch K5 and the differential-to-single-ended module. The second end of resistor R9 is connected to the first end of resistor R10, the first end of capacitor C1 and the first end of switch K6. The second ends of resistor R10 and capacitor C1 are both grounded. The second end of switch K6 is connected to the second end of switch K5 and the non-inverting input of operational amplifier U4.

[0016] The inverting input terminal of the operational amplifier U4 is connected to the first terminal of the switch K8, the first terminal of the resistor R13, and the first terminal of the switch K7. The second terminal of the switch K8 is connected to the first terminal of the resistor R11 and the first terminal of the resistor R12. The second terminal of the resistor R11 is grounded. The output terminal of the operational amplifier U4 is connected to the second terminal of the resistor R12, the second terminal of the resistor R13, the second terminal of the switch K7, and the single-ended to differential converter module.

[0017] In one embodiment, the single-ended to differential module includes a differential amplifier U5, an analog-to-digital converter U6, resistors R14, R15, R16, R17, R18, R19, capacitors C2, C3, C4, C5, and C6.

[0018] The first end of resistor R14 is connected to the gain adjustment module. The second end of resistor R14 is connected to the non-inverting input terminal of differential amplifier U5, the first end of resistor R17, and the first end of capacitor C2. The second ends of resistor R17 and capacitor C2 are both connected to the first output terminal of differential amplifier U5. The first end of resistor R15 is connected to the inverting input terminal of differential amplifier U5, the first end of resistor R16, and the first end of capacitor C3. The second end of resistor R15 is grounded. The second ends of resistor R16 and capacitor C3 are both connected to the second output terminal of differential amplifier U5.

[0019] The first output terminal of the differential amplifier U5 is connected to the first terminal of the resistor R19, the second output terminal of the differential amplifier U5 is connected to the first terminal of the resistor R18, the second terminal of the resistor R19 is connected to the first terminal of the capacitor C4, the first terminal of the capacitor C5 and the analog-to-digital converter U6, the second terminal of the capacitor C4 is grounded, the second terminal of the resistor R18 is connected to the second terminal of the capacitor C5, the first terminal of the capacitor C6 and the analog-to-digital converter U6, the second terminal of the capacitor C6 is grounded.

[0020] A second aspect of this application provides a mixed-signal board, including a DC calibration device and a functional module connected to each other.

[0021] In one embodiment, the functional module includes an AWG, a DGT, a zeroing DAC, an AWG common-mode DAC, and a DGT common-mode DAC; the AWG, the zeroing DAC, and the AWG common-mode DAC are connected to the board's DC calibration device through an AWG analog front-end channel, and the DGT and the DGT common-mode DAC are both connected to the AWG analog front-end channel and the board's DC calibration device through a DGT analog front-end channel.

[0022] In one embodiment, the mixed-signal board further includes a grounding switch KA and a grounding switch KB, wherein a first terminal of the grounding switch KA is connected to a first channel of the DGT analog front-end channel and a second terminal of the grounding switch KA is grounded, and a first terminal of the grounding switch KB is connected to a second channel of the DGT analog front-end channel and a second terminal of the grounding switch KB is grounded.

[0023] In one embodiment, the mixed-signal board further includes a multimeter disposed outside the board, the multimeter being connected to the functional module for measuring the output signal of the functional module to obtain reference data for calibrating the board's DC calibration device.

[0024] In one embodiment, there are two or more mixed-signal boards, and each mixed-signal board is equipped with a corresponding board DC calibration device; the multimeter calibrates each board DC calibration device through a calibration bus, and each board DC calibration device calibrates the corresponding functional module in parallel.

[0025] The aforementioned DC calibration device and mixed-signal board utilize a differential-to-single-ended module. This module receives the output signal from the functional module, outputs a single-ended signal to a gain adjustment module, adjusts the gain of the received single-ended signal, and outputs the adjusted single-ended signal to a single-ended-to-differential module. This module converts the received single-ended signal into a differential signal, acquires the signal, and outputs the acquired data for calibrating the functional module. Integrating the DC calibration device within the board reduces the number of external components required for board calibration, supports parallel calibration of multiple boards, and improves calibration efficiency. Attached Figure Description

[0026] Figure 1 This is a structural block diagram of the board DC calibration device in one embodiment;

[0027] Figure 2 This is a schematic diagram of the board-based DC calibration device in one embodiment;

[0028] Figure 3 This is a schematic diagram of the differential external calibration principle in one embodiment;

[0029] Figure 4This is a schematic diagram of the single-ended P external calibration principle in one embodiment;

[0030] Figure 5 This is a schematic diagram of the single-ended N-type external calibration principle in one embodiment;

[0031] Figure 6 This is a schematic diagram of the AWG differential internal calibration principle in one embodiment;

[0032] Figure 7 This is a schematic diagram of the internal calibration principle of AWG single-ended P in one embodiment;

[0033] Figure 8 This is a schematic diagram of the AWG single-ended N-internal calibration principle in one embodiment;

[0034] Figure 9 This is a schematic diagram of the DGT differential internal calibration principle in one embodiment;

[0035] Figure 10 This is a schematic diagram of the DGT single-ended P internal calibration principle in one embodiment;

[0036] Figure 11 This is a schematic diagram of the DGT single-ended N-internal calibration principle in one embodiment;

[0037] Figure 12 This is a schematic diagram of the DGT common-mode P internal calibration principle in one embodiment;

[0038] Figure 13 This is a schematic diagram of the DGT common-mode N-internal calibration principle in one embodiment;

[0039] Figure 14 This is a schematic diagram illustrating the parallel calibration principle of multiple boards in one embodiment. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0042] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0043] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, operations, components, parts, or combinations thereof.

[0044] In one embodiment, such as Figure 1 As shown, a board-based DC calibration device is provided, including a differential-to-single-ended module 110, a gain adjustment module 120, and a single-ended-to-differential module 130, which are disposed within the board and connected in sequence. The differential-to-single-ended module 110 is connected to the functional modules in the board, receives the output signals of the functional modules, and outputs a single-ended signal to the gain adjustment module 120. The gain adjustment module 120 adjusts the gain of the received single-ended signal and outputs the adjusted single-ended signal to the single-ended-to-differential module 130. The single-ended-to-differential module 130 converts the adjusted single-ended signal into a differential signal, performs signal acquisition, and outputs the acquired data for calibrating the functional modules.

[0045] The type of functional module is not unique and may include at least one of AWG (Arbitrary Waveform Generator), DGT (Arbitrary Waveform Acquisition Module), Zero-adjustment DAC (Analog-to-Digital Converter), and Common-mode DAC. The differential-to-single-ended module 110 can be a differential or single-ended channel connected to the functional module, receiving the differential or single-ended signal output from the functional module and outputting a single-ended signal to the gain adjustment module 120. The gain adjustment module 120 may be set to a fixed gain or may have two or more gain levels, such as three switchable gain levels: -10.7dB, 0dB, and 6dB. The gain adjustment module 120 adjusts the gain of the received single-ended signal according to different gain levels and outputs the adjusted single-ended signal to the single-ended-to-differential module 130. The single-ended-to-differential module 130 converts the adjusted single-ended signal into a differential signal, acquires the signal, and outputs the acquired data corresponding to different gain levels for use in calibrating the functional module. The host computer can be connected to the function module and the single-ended to differential module 130 to control the function module to output differential or single-ended signals, and to calibrate the function module according to the acquisition data corresponding to different gain levels output by the single-ended to differential module 130.

[0046] Furthermore, such as Figure 2As shown, the device also includes a link switching module 140 disposed within the board. The link switching module 140 connects the differential-to-single-ended module 120, the functional modules, and the ground terminal. The link switching module 140 is used to connect the input port of the differential-to-single-ended module 120 to the functional modules or the ground terminal, so that the input port of the differential-to-single-ended module 120 receives the differential signal or single-ended signal output by the functional modules. The link switching module 140 can be connected to the analog front-end channel via the calibration buses DCC_HS and DCC_LS within the board, and then connected to each functional module via the analog front-end channel.

[0047] The link switching module 140 may specifically include switches K1, K2, K3, and K4. The first end of switch K1 is connected to the differential-to-single-ended module 120, and the second end of switch K1 is connected to the ground terminal. The first end of switch K2 is connected to the differential-to-single-ended module 120, and the second end of switch K2 is connected to the functional module through the terminal CAL_BUS_HS. The first end of switch K3 is connected to the differential-to-single-ended module 120, and the second end of switch K3 is connected to the ground terminal. The first end of switch K4 is connected to the differential-to-single-ended module 120, and the second end of switch K4 is connected to the functional module through the terminal CAL_BUS_LS. Switches K1, K2, K3, and K4 can all be relays. When switches K2 and K4 are closed and switches K1 and K3 are open, the differential-to-single-ended module 120 receives the differential signal. When switches K1 and K4 are open and switches K2 and K3 are closed, or when switches K1 and K4 are closed and switches K2 and K3 are open, the differential-to-single-ended module 120 receives the corresponding single-ended signal.

[0048] In one embodiment, the differential-to-single-ended converter 110 includes operational amplifiers U1, U2, and U3, and resistors R1, R2, R3, R4, R5, R6, R7, and R8. The inverting input of operational amplifier U1 is connected to the first terminals of resistors R1 and R3, and the non-inverting input of operational amplifier U1 is connected to the link switching module 140, specifically to the first terminals of switches K1 and K2. The output of operational amplifier U1 is connected to the second terminals of resistors R3 and R5, and the second terminal of resistor R5 is connected to the inverting input of operational amplifier U3. The second terminal of resistor R1 is connected to the first terminal of resistor R2, and the second terminal of resistor R2 is connected to the inverting input of operational amplifier U2. The inverting input of operational amplifier U2 is connected to the first terminal of resistor R4, and the non-inverting input of operational amplifier U2 is connected to the link switching module 110, specifically to the first terminals of switches K3 and K4. The output of operational amplifier U2 is connected to the second terminal of resistor R4 and the first terminal of resistor R6. The second terminal of resistor R6 is connected to the non-inverting input of operational amplifier U3 and the first terminal of resistor R8. The second terminal of resistor R8 is grounded. The inverting input of operational amplifier U3 is connected to the first terminal of resistor R7. The output of operational amplifier U3 is connected to the second terminal of resistor R7 and the gain adjustment module 120.

[0049] Furthermore, the gain adjustment module 120 may include an operational amplifier U4, resistors R9, R10, R11, R12, and R13, switches K5, K6, K7, and K8, and a capacitor C1. Switches K5, K6, K7, and K8 may also be relays. The first terminal of resistor R9 is connected to the first terminal of switch K5 and the differential-to-single-ended module 110, specifically connected to the output terminal of operational amplifier U3. The second terminal of resistor R9 is connected to the first terminal of resistor R10, the first terminal of capacitor C1, and the first terminal of switch K6. The second terminals of resistor R10 and capacitor C1 are both grounded. The second terminal of switch K6 is connected to the second terminal of switch K5 and the non-inverting input terminal of operational amplifier U4. The inverting input of operational amplifier U4 is connected to the first terminal of switch K8, the first terminal of resistor R13, and the first terminal of switch K7. The second terminal of switch K8 is connected to the first terminal of resistor R11 and the first terminal of resistor R12. The second terminal of resistor R11 is grounded. The output of operational amplifier U4 is connected to the second terminal of resistor R12, the second terminal of resistor R13, the second terminal of switch K7, and the single-ended to differential module 130.

[0050] In addition, the single-ended to differential module 130 includes a differential amplifier U5, an analog-to-digital converter U6, resistors R14, R15, R16, R17, R18, and R19, and capacitors C2, C3, C4, C5, and C6. The analog-to-digital converter U6 can be a sampling ADC. The first end of resistor R14 is connected to the gain adjustment module 120, specifically to the output of operational amplifier U4. The second end of resistor R14 is connected to the non-inverting input of differential amplifier U5, the first end of resistor R17, and the first end of capacitor C2. The second ends of resistor R17 and capacitor C2 are both connected to the first output of differential amplifier U5. The first end of resistor R15 is connected to the inverting input of differential amplifier U5, the first end of resistor R16, and the first end of capacitor C3. The second end of resistor R15 is grounded. The second ends of resistor R16 and capacitor C3 are both connected to the second output of differential amplifier U5.

[0051] The first output terminal of differential amplifier U5 is connected to the first terminal of resistor R19, the second output terminal of differential amplifier U5 is connected to the first terminal of resistor R18, the second terminal of resistor R19 is connected to the first terminal of capacitor C4, the first terminal of capacitor C5 and analog-to-digital converter U6, the second terminal of capacitor C4 is grounded, the second terminal of resistor R18 is connected to the second terminal of capacitor C5, the first terminal of capacitor C6 and analog-to-digital converter U6, the second terminal of capacitor C6 is grounded.

[0052] In one embodiment, a mixed-signal board is also provided, including the aforementioned board DC calibration device and functional modules interconnected. The functional modules may include at least one of an AWG, a DGT, a zero-adjustment DAC, an AWG common-mode DAC, and a DGT common-mode DAC.

[0053] The mixed-signal board also includes a multimeter located outside the board. The multimeter connects to the functional modules and measures their output signals to obtain reference data for calibrating the board's DC calibration device. Furthermore, there are two or more mixed-signal boards, each equipped with a corresponding DC calibration device. The multimeter measures the output signals of the functional modules in each board to obtain the reference data required for calibrating the corresponding board's DC calibration device. The multimeter calibrates each board's DC calibration device via a calibration bus, and each board's DC calibration device calibrates its corresponding functional module in parallel. By simply connecting the multimeter to the shared calibration bus within the boards, collecting reference data, and calibrating the sampling ADC in each board's DC calibration device (completing external calibration), the calibrated board's DC calibration device can then be used to perform internal calibration on the corresponding functional modules on the board. This allows for synchronous calibration of all boards, improving calibration efficiency.

[0054] like Figure 3As shown, the board-based DC calibration device built using a sampling ADC includes a differential-to-single-ended module 110, a gain adjustment module 120, and a single-ended-to-differential module 130. A multimeter is connected to the calibration bus in the board via an RF cable and backplane traces to collect reference data for external calibration of the sampling ADC. Then, the externally calibrated sampling ADC is used to perform internal calibration of the functional modules in the board. The functional modules include five parts: AWG, DGT, Zero DAC, AWG Common Mode DAC, and DGT Common Mode DAC.

[0055] First, external calibration of the sampling ADC is performed. The calibration sequence is: first, calibrate the differential path; then, calibrate the single-ended P path; and finally, calibrate the single-ended N path. The calibration items are selected on the host computer calibration software. After the host computer software recognizes the selection, it begins initialization. Upon completion of initialization, configuration data for each module is sent. During differential calibration, the AWG P and N links of the main DAC inside the board receive control data from the FPGA and begin outputting an uncalibrated linear voltage, ranging from -1 to 1V in 0.16V steps. The AWG Zero DAC and AWG Com DAC receive control data transmitted from the FPGA and output an uncalibrated 0V to the AWG main link. A relay switches the connection between the AWG main link and the calibration buses DCC_HS and DCC_LS, transmitting data to the board's DC calibration device. The sampling ADC and a high-precision multimeter collect data across three gain levels. The data link is as follows: Figure 3 The red line represents the data flow path, while the blue line represents a disconnection. After comparing the data from the sampling ADC with that collected by the multimeter, the differential calibration parameters of the sampling ADC are obtained through linear fitting.

[0056] During single-ended P calibration, the AWG P-link main DAC inside the board receives control data from the FPGA and begins outputting an uncalibrated linear voltage, ranging from -1 to 1V in 0.16V steps. The AWG Zero DAC and AWG Com DAC receive control data from the FPGA and output an uncalibrated 0V to the AWG main link. A relay switches the connection between the AWG main link and the DCC_HS line, transmitting data to the board's DC calibration device. The sampling ADC and a high-precision multimeter collect data across three gain levels. The DCC_LS line is grounded, i.e., switch K3 is closed, and the data link is as follows... Figure 4 After comparing the data collected by the sampling ADC with that collected by the multimeter, the calibration parameters of the P-terminal of the sampling ADC are obtained through linear fitting calculation.

[0057] During single-ended N-calibration, the AWG N-link main DAC inside the board receives control data from the FPGA and begins outputting an uncalibrated linear voltage, ranging from -1 to 1V in 0.16V steps. The AWG Zero DAC and AWG Com DAC receive control data from the FPGA and output an uncalibrated 0V to the AWG main link. A relay switches the connection between the AWG main link and the DCC_LS line, transmitting data to the board's DC calibration device. The sampling ADC and a high-precision multimeter collect data across three gain levels. The DCC_HS line is grounded, i.e., K1 is closed. The data link is as follows... Figure 5 After comparing the data acquired by the sampling ADC with that acquired by the multimeter, the N-terminal calibration parameters of the sampling ADC are obtained through linear fitting calculation.

[0058] The AWG, zeroing DAC, and AWG common-mode DAC are connected to the board's DC calibration device via the AWG analog front-end channel. The DGT and DGT common-mode DAC are both connected to the AWG analog front-end channel and the board's DC calibration device via the DGT analog front-end channel. Both the AWG and DGT analog front-end channels contain filter circuits and gain circuits (specific circuit structures are not shown in the figure), but the specific circuit structures of the AWG and DGT analog front-end channels are different.

[0059] The internal calibration process of the board is as follows:

[0060] After external calibration is successful, internal calibration begins. During internal calibration, the reference standard is the data acquired by the sampling ADC, which has already applied the calibration parameters from the external calibration. The internal calibration execution sequence is: AWG Zero DAC, AWG Com DAC, AWG, DGT, DGT Com DAC. Each functional module is connected to the calibration bus via an analog front-end channel. The circuitry in the DC calibration device, excluding the sampling ADC, serves as the analog front-end, connecting the sampling ADC to the calibration bus.

[0061] When calibrating the AWG Zero DAC, only the differential output is calibrated. The AWG Zero DAC link output is an uncalibrated linear voltage, ranging from -13V to 13V in 2.6V steps. The AWG and AWG Com DAC outputs are also uncalibrated at 0V. Data is transmitted to the board's DC calibration device via the calibration buses DCC_HS and DCC_LS. The sampling ADC acquires data across three gain levels. Linear fitting calculations are performed based on the output and acquired values ​​to obtain the AWG Zero DAC calibration parameters. The data link is as follows... Figure 6 .

[0062] When calibrating the AWG Com DAC, only the single-ended output is calibrated. When calibrating the single-ended P-terminal, the AWG Com DAC's P-terminal output is an uncalibrated linear voltage, ranging from -3.2V to 3.2V in 0.64V steps. The AWG outputs an uncalibrated 0V, while the AWG Zero DAC outputs a calibrated 0V. Data is transmitted to the board's DC calibration device via line DCC_HS. The sampling ADC collects data across three gain levels. Line DCC_LS is grounded, i.e., switch K3 is closed. Linear fitting calculations are performed based on the output and collected values ​​to obtain the AWG Com DAC's P-terminal calibration parameters. The data link is as follows... Figure 7 .

[0063] When calibrating the single-ended N-terminal, the N-terminal link output of the AWG Com DAC is an uncalibrated linear voltage, ranging from -3.2V to 3.2V in 0.64V steps. The AWG outputs an uncalibrated 0V, while the AWG Zero DAC outputs a calibrated 0V. Data is transmitted to the board's DC calibration device via line DCC_LS. The sampling ADC collects data across three gain levels. Line DCC_HS is grounded, i.e., switch K1 is closed. Linear fitting calculations are performed based on the output and collected values ​​to obtain the N-terminal calibration parameters of the AWG Com DAC. The data link is as follows: Figure 8 .

[0064] When calibrating the AWG, the calibration sequence is as follows: first calibrate the differential path, then calibrate the single-ended P path, and finally calibrate the single-ended N path. The AWG differential outputs an uncalibrated linear voltage in six ranges (Vrange): 0.53V, 0.75V, 1.061V, 1.5V, 2.121V, and 3.0V, ranging from -Vrange to +Vrange. The step voltage value is the current range value divided by 6. The AWG Zero DAC and AWG ComDAC output calibrated 0V. Data is transmitted to the board's DC calibration device via the calibration buses DCC_HS and DCC_LS. The sampling ADC acquisition end uses a 0dB gain link. The differential calibration parameters of the AWG are obtained by linear fitting calculation based on the output and acquired values. The data link is as follows... Figure 6 .

[0065] When calibrating the single-ended P, the AWG_P link outputs an uncalibrated linear voltage in six ranges (Vrange): 0.53V, 0.75V, 1.061V, 1.5V, 2.121V, and 3.0V, ranging from -Vrange / 2 to +Vrange / 2. The step voltage value is the current range value divided by 12. The AWG Zero DAC and AWG Com DAC output calibrated 0V. This is transmitted to the board's DC calibration device via line DCC_HS. The sampling ADC acquisition end uses a 0dB gain link, and line DCC_LS is grounded. Linear fitting calculations are performed based on the output and acquired values ​​to obtain the AWG's P-end calibration parameters. The data link is as follows... Figure 7 .

[0066] When calibrating the single-ended N, the AWG_N terminal link outputs an uncalibrated linear voltage in six ranges (Vrange): 0.53V, 0.75V, 1.061V, 1.5V, 2.121V, and 3.0V, ranging from -Vrange / 2 to +Vrange / 2. The step voltage value is the current range value divided by 12. The AWG Zero DAC and AWG Com DAC output calibrated 0V. This is transmitted to the board's DC calibration device via line DCC_LS. The sampling ADC acquisition end uses a 0dB gain link, and line DCC_HS is grounded. Linear fitting calculations are performed based on the output and acquired values ​​to obtain the AWG's N-terminal calibration parameters. The data link is as follows... Figure 8 .

[0067] like Figure 9 As shown, the mixed-signal board also includes grounding switches KA and KB. The first terminal of grounding switch KA is connected to the first channel (P-channel) of the DGT analog front-end channel, and the second terminal of grounding switch KA is grounded. The first terminal of grounding switch KB is connected to the second channel (N-channel) of the DGT analog front-end channel, and the second terminal of grounding switch KB is grounded. Grounding switches KA and KB can also be relays; by switching the on and off states of grounding switches KA and KB, differential and single-ended signal transmission can be achieved.

[0068] When calibrating the DGT, the calibration sequence is as follows: first calibrate the differential path, then calibrate the single-ended P path, and finally calibrate the single-ended N path. AWG outputs linear calibration voltages in eight ranges (Vrange): 0.265V, 0.31V, 0.44V, 0.75V, 0.88V, 1.25V, 1.76V, and 2.5V, ranging from -Vrange to +Vrange. The step voltage value is the current range value divided by 6. The AWG Zero DAC and AWGCom DAC output 0V after calibration. Data is transmitted to the board's DC calibration device via the calibration buses DCC_HS and DCC_LS. The sampling ADC acquisition end uses a 0dB gain link, and the internal LOOP loop transmits data to the DGT circuit acquisition end. The differential calibration parameters of the DGT are obtained by linear fitting calculation based on the voltage sequence of the sampled ADC and DGT differential circuit. The data link is as follows... Figure 9 .

[0069] When calibrating single-ended P, the AWG_P link outputs a linear calibration voltage in eight ranges (Vrange): 0.265V, 0.31V, 0.44V, 0.75V, 0.88V, 1.25V, 1.76V, and 2.5V. The range is -Vrange / 2 to +Vrange / 2, with each step voltage value divided by 12. The AWG Zero DAC and AWG Com DAC output 0V after calibration. The voltage is transmitted to the board's DC calibration device via line DCC_HS. The sampling ADC acquisition end uses a 0dB gain link, and line DCC_LS is grounded (i.e., switch K3 is closed). The internal LOOP_P loop transmits the data to the DGT_P acquisition end, and the LOOP_N loop is grounded. Linear fitting calculations are performed based on the output and acquired values ​​to obtain the DGT's P-end calibration parameters. The data link is as follows... Figure 10 .

[0070] When calibrating the single-ended N, the AWG_N terminal link outputs a linear calibration voltage in eight ranges (Vrange): 0.265V, 0.31V, 0.44V, 0.75V, 0.88V, 1.25V, 1.76V, and 2.5V. The range is -Vrange / 2 to +Vrange / 2, with the step voltage value being the current range value divided by 12. The AWG Zero DAC and AWG Com DAC output 0V after calibration. The voltage is transmitted to the board's DC calibration device via line DCC_LS. The sampling ADC acquisition end uses a 0dB gain link, and line DCC_HS is grounded (i.e., switch K1 is closed). The internal LOOP_N loop transmits the data to the DGT_N acquisition end, and the LOOP_P loop is grounded. Linear fitting calculations are performed based on the output and acquired values ​​to obtain the N-terminal calibration parameters of the DGT. The data link is as follows... Figure 11 .

[0071] When calibrating the DGT Com DAC, only the single-ended pin is calibrated. During single-ended P calibration, the AWG, AWG Zero DAC, and AWG Com DAC output 0V after calibration. The P-end link of the DGT Com DAC outputs a linear calibration voltage in eight ranges (Vrange): 0.265V, 0.31V, 0.44V, 0.75V, 0.88V, 1.25V, 1.76V, and 2.5V, ranging from -Vrange / 2 to +Vrange / 2. The step voltage value is the current range value divided by 12. This voltage is transmitted to the acquisition terminal of the DGT_P circuit. The DGT_N circuit is grounded. The P-end calibration parameters of the DGT Com DAC are obtained by linear fitting calculation based on the voltage sequence acquired from the DGT_P circuit. The data link is as follows: Figure 12 .

[0072] When calibrating the single-ended N, the AWG, AWG Zero DAC, and AWG Com DAC output 0V after calibration. The N-terminal link of the DGT Com DAC outputs a linear calibration voltage in eight ranges (Vrange): 0.265V, 0.31V, 0.44V, 0.75V, 0.88V, 1.25V, 1.76V, and 2.5V, ranging from -Vrange / 2 to +Vrange / 2. The step voltage value is the current range value divided by 12. This voltage is transmitted to the acquisition terminal of the DGT_N circuit. The DGT_P circuit is grounded. The N-terminal calibration parameters of the DGT Com DAC are obtained by linear fitting calculation based on the voltage sequence acquired by the DGT_N circuit. The data link is as follows: Figure 13 .

[0073] The verification process is as follows:

[0074] After calibration, a verification is performed. The verification order is the same as the calibration order: first, the external DC calibration device is verified, and then the four internal components, namely AWG, DGT, zeroing DAC and common-mode DAC, are verified.

[0075] The verification process is exactly the same as the calibration process, the difference being that all output voltage values ​​are calibrated data. When using the external calibration board's DC calibration device, the difference between the data collected by the sampling ADC and the data collected by the high-precision multimeter is compared to see if it is less than the ORDR accuracy index. If it is less, the verification passes; otherwise, the verification fails, the verification process is directly interrupted, and the verification data is output.

[0076] During internal calibration of the AWG loop, the difference between the sampled ADC value and the data sent by the AWG is compared to see if it is less than the ORDR accuracy index. If it is, the calibration passes; otherwise, the calibration fails, the calibration process is interrupted, and the calibration data is output. During internal calibration of the DGT loop, the difference between the sampled ADC value and the data collected by the DGT is compared to see if it is less than the ORDR accuracy index. If it is, the calibration passes; otherwise, the calibration fails, the calibration process is interrupted, and the calibration data is output.

[0077] Furthermore, during parallel calibration and verification of multiple boards in the entire system, the external calibration and verification of each board is performed sequentially first to complete the calibration of the board's DC calibration device. External calibration requires a high-precision multimeter, while system-wide calibration uses only one shared calibration bus (DCC_HS, DCC_LS), thus requiring serial calibration. Internal calibration involves a DC calibration device within each board, enabling synchronous calibration of all boards. The calibration layout in the entire system is as follows: Figure 14 .

[0078] The DC calibration device and hybrid analog-to-digital board provided in this application add a DC calibration device based on sampling ADC inside the board, and multiple boards share a single calibration bus to realize single instrument multi-board calibration, support multi-board parallel calibration, and improve calibration efficiency.

[0079] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A board-based DC calibration device, characterized in that, This includes a differential-to-single-ended module, a gain adjustment module, and a single-ended-to-differential module, all installed within the board and connected in sequence. The differential-to-single-ended module is connected to the functional module in the board, receives the output signal of the functional module, and outputs a single-ended signal to the gain adjustment module. The gain adjustment module adjusts the gain of the received single-ended signal and outputs the adjusted single-ended signal to the single-ended to differential module. The single-ended to differential module converts the adjusted single-ended signal into a differential signal for signal acquisition and outputs the acquired data for calibrating the functional module.

2. The apparatus according to claim 1, characterized in that, It also includes a link switching module disposed within the board, the link switching module being connected to the differential-to-single-ended module, the functional module, and the ground terminal; the link switching module is used to connect the input port of the differential-to-single-ended module to the functional module or the ground terminal, so that the input port of the differential-to-single-ended module receives the differential signal or single-ended signal output by the functional module.

3. The apparatus according to claim 2, characterized in that, The differential-to-single-ended module includes operational amplifier U1, operational amplifier U2, operational amplifier U3, resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7 and resistor R8; The inverting input terminal of the operational amplifier U1 is connected to the first terminal of the resistor R1 and the first terminal of the resistor R3. The non-inverting input terminal of the operational amplifier U1 is connected to the link switching module. The output terminal of the operational amplifier U1 is connected to the second terminal of the resistor R3 and the first terminal of the resistor R5. The second terminal of the resistor R5 is connected to the inverting input terminal of the operational amplifier U3. The second end of resistor R1 is connected to the first end of resistor R2. The second end of resistor R2 is connected to the inverting input of operational amplifier U2. The inverting input of operational amplifier U2 is connected to the first end of resistor R4. The non-inverting input of operational amplifier U2 is connected to the link switching module. The output of operational amplifier U2 is connected to the second end of resistor R4 and the first end of resistor R6. The second end of resistor R6 is connected to the non-inverting input of operational amplifier U3 and the first end of resistor R8. The second end of resistor R8 is grounded. The inverting input terminal of the operational amplifier U3 is connected to the first terminal of the resistor R7, and the output terminal of the operational amplifier U3 is connected to the second terminal of the resistor R7 and the gain adjustment module.

4. The apparatus according to claim 1, characterized in that, The gain adjustment module has two or more gain levels. It adjusts the gain of the received single-ended signal according to different gain levels and outputs the adjusted single-ended signal to the single-ended to differential module. The single-ended to differential module converts the received single-ended signal into a differential signal and then acquires the signal, outputting the acquired data corresponding to different gain levels for use in calibrating the functional module.

5. The apparatus according to claim 4, characterized in that, The gain adjustment module includes an operational amplifier U4, resistors R9, R10, R11, R12, and R13, switches K5, K6, K7, and K8, and a capacitor C1. The first end of resistor R9 is connected to the first end of switch K5 and the differential-to-single-ended module. The second end of resistor R9 is connected to the first end of resistor R10, the first end of capacitor C1 and the first end of switch K6. The second ends of resistor R10 and capacitor C1 are both grounded. The second end of switch K6 is connected to the second end of switch K5 and the non-inverting input of operational amplifier U4. The inverting input terminal of the operational amplifier U4 is connected to the first terminal of the switch K8, the first terminal of the resistor R13, and the first terminal of the switch K7. The second terminal of the switch K8 is connected to the first terminal of the resistor R11 and the first terminal of the resistor R12. The second terminal of the resistor R11 is grounded. The output terminal of the operational amplifier U4 is connected to the second terminal of the resistor R12, the second terminal of the resistor R13, the second terminal of the switch K7, and the single-ended to differential converter module.

6. The apparatus according to claim 1, characterized in that, The single-ended to differential module includes a differential amplifier U5, an analog-to-digital converter U6, resistors R14, R15, R16, R17, R18, and R19, and capacitors C2, C3, C4, C5, and C6. The first end of resistor R14 is connected to the gain adjustment module. The second end of resistor R14 is connected to the non-inverting input terminal of differential amplifier U5, the first end of resistor R17, and the first end of capacitor C2. The second ends of resistor R17 and capacitor C2 are both connected to the first output terminal of differential amplifier U5. The first end of resistor R15 is connected to the inverting input terminal of differential amplifier U5, the first end of resistor R16, and the first end of capacitor C3. The second end of resistor R15 is grounded. The second ends of resistor R16 and capacitor C3 are both connected to the second output terminal of differential amplifier U5. The first output terminal of the differential amplifier U5 is connected to the first terminal of the resistor R19, the second output terminal of the differential amplifier U5 is connected to the first terminal of the resistor R18, the second terminal of the resistor R19 is connected to the first terminal of the capacitor C4, the first terminal of the capacitor C5 and the analog-to-digital converter U6, the second terminal of the capacitor C4 is grounded, the second terminal of the resistor R18 is connected to the second terminal of the capacitor C5, the first terminal of the capacitor C6 and the analog-to-digital converter U6, the second terminal of the capacitor C6 is grounded.

7. A mixed-signal board, characterized in that, It includes the board DC calibration device and functional modules of any one of claims 1-6 that are interconnected.

8. The hybrid modular board according to claim 7, characterized in that, The functional modules include AWG, DGT, zeroing DAC, AWG common-mode DAC, and DGT common-mode DAC; the AWG, the zeroing DAC, and the AWG common-mode DAC are connected to the board's DC calibration device through the AWG analog front-end channel, and the DGT and the DGT common-mode DAC are both connected to the AWG analog front-end channel and the board's DC calibration device through the DGT analog front-end channel.

9. The hybrid modular board according to claim 8, characterized in that, It also includes a grounding switch KA and a grounding switch KB. The first end of the grounding switch KA is connected to the first channel of the DGT analog front-end channel, and the second end of the grounding switch KA is grounded. The first end of the grounding switch KB is connected to the second channel of the DGT analog front-end channel, and the second end of the grounding switch KB is grounded.

10. The hybrid modular board according to claim 7, characterized in that, It also includes a multimeter located outside the board, which is connected to the functional module and used to measure the output signal of the functional module to obtain reference data for calibrating the DC calibration device of the board.

11. The hybrid modular board according to claim 10, characterized in that, The number of the mixed analog-digital board is two or more, and each of the mixed analog-digital boards is equipped with a corresponding board DC calibration device; the multimeter calibrates each of the board DC calibration devices through the calibration bus, and each of the board DC calibration devices calibrates the corresponding functional modules in parallel.

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