Analog comparator and chip

Abstract

The invention discloses an analog comparator and a chip, and relates to the technical field of circuit testing. The analog comparator comprises an analog testing bus, a comparator, a first signal interface, a second signal interface and an analog-to-digital converter signal interface, the simulation test bus comprises a sensing bus and is used for transmitting a to-be-tested simulation signal of a to-be-tested simulation circuit module to the first signal interface or the analog-to-digital converter signal interface for testing; the second signal interface is used for receiving an externally input driving signal and transmitting the driving signal to the analog circuit module to be tested; the comparator is used for comparing an input signal with a reference voltage and outputting a comparison result; the input signal comprises the analog signal to be detected. By adopting the analog comparator, the test efficiency can be improved, and the test cost can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit testing, and in particular to an analog comparator and a chip. Background Art

[0002] In chip design, especially the design of automotive-grade chips, in order to meet the specifications of automotive electronic components, higher performance requirements are imposed on them. For example, the temperature range, working stability, reliability and other requirements are higher than those of traditional chip design.

[0003] The design of analog circuit modules is of utmost importance in chip design. The measurement of analog circuit modules is an important means to check the quality of module design, and the measurement method is required to be fast and accurate. In related technologies, analog comparators (ACMP) are used to detect the output voltage of analog circuit modules, and most of their input signals are voltage signals. ACMP can use multi-channel input to meet the needs of different voltage segments to be tested, but more technologies are still needed to realize functions such as debug circuits and current testing. Summary of the invention

[0004] Based on this, it is necessary to provide an analog comparator and chip that can improve the test efficiency and test function of the analog circuit module in order to address the above technical problems.

[0005] An analog comparator comprises an analog test bus, a comparator, a first signal interface, a second signal interface and an analog-to-digital converter signal interface; the analog test bus comprises a sensing bus, which is used to transmit an analog signal to be tested of an analog circuit module to be tested to the first signal interface or the analog-to-digital converter signal interface for testing; The second signal interface is used to receive an external driving signal and transmit the driving signal to the analog circuit module to be tested; The comparator is used to compare an input signal with a reference voltage and output a comparison result; the input signal includes the analog signal to be measured.

[0006] In the above scheme, the first input end of the comparator is connected to the first channel multiplexer, and the second input end of the comparator is connected to the second channel multiplexer; the input signal of the comparator is input through the first channel multiplexer or the second channel multiplexer; wherein, One port in the first channel multiplexer is connected to the sensing bus; one port in the second channel multiplexer is connected to the second signal interface; and the remaining ports in the first channel multiplexer and the second channel multiplexer are used to receive external analog signals.

[0007] In the above solution, the reference voltage is input through the first channel multiplexer or the second channel multiplexer.

[0008] In the above solution, the reference voltage is input through the first signal interface or the second signal interface.

[0009] In the above scheme, the analog test bus also includes a digital-to-analog converter bus, and the analog comparator also includes a digital-to-analog converter, a first data selector, a second data selector, a third data selector and a buffer; The digital-to-analog converter and the analog signal to be measured are respectively connected to the first data selector; the first data selector is connected to the input end of the buffer; The output end of the buffer is connected to the second data selector and the third data selector respectively; the analog signal to be measured is connected to the second data selector via the sensing bus; the digital-to-analog converter is connected to the third data selector via the digital-to-analog converter bus; The second data selector is connected to the first input terminal of the comparator; the third data selector is connected to the second input terminal of the comparator; The digital-to-analog converter provides the reference voltage to the comparator through the second data selector or the third data selector.

[0010] In the above scheme, the analog comparator also includes a third signal interface; the third signal interface is connected to the third data selector; the digital-to-analog converter also provides a reference voltage to the analog circuit module connected to the third signal interface through the digital-to-analog converter bus.

[0011] In the above solution, the digital-to-analog converter is respectively connected to a first voltage generated by an internal circuit and a second voltage generated by an external circuit, so as to select the first voltage or the second voltage as the reference voltage.

[0012] In the above solution, the analog signal to be measured is a current signal to be measured, and the digital-to-analog converter converts the current signal to be measured into a voltage signal to be measured, and transmits it to the first signal interface or the analog-to-digital converter signal interface for testing.

[0013] In the above solution, the current signal to be measured is connected from the third signal interface.

[0014] A chip comprises the analog comparator in the above solution.

[0015] The above-mentioned analog comparator and chip include an analog test bus, a comparator, a first signal interface, a second signal interface and an analog-to-digital converter signal interface. The perception bus in the analog test bus can transmit the analog signal to be tested of the analog circuit module to be tested to the first signal interface or the analog-to-digital converter signal interface for testing; the drive signal can be input to the analog comparator through the second signal interface; the comparator supports the comparison of the input signal with the reference voltage. Based on this, by adding an analog test bus to the analog comparator, the analog comparator can support both the perception test and the drive signal input, and the perception test and the drive signal input are independent of each other and can work at the same time, thereby saving test time and reducing test costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of the structure of an analog comparator in one embodiment; Figure 2 A schematic diagram of a structure of an analog comparator supporting multi-channel input in one embodiment; Figure 3 A schematic diagram of the connection of a digital-to-analog converter in an analog comparator in one embodiment; Figure 4 FIG. 4 is a connection diagram of a third signal interface in an analog comparator in an embodiment.

[0017] Reference numerals: Sensing bus SNS_BUS, comparator CMP, first signal interface SNSCE PAD, second signal interface FORCEPAD, third signal interface FRCOUT, analog-to-digital converter signal interface SNSCOMMON TO ADC, first channel multiplexer PMUX, second channel multiplexer NMUX, digital-to-analog converter RDAC, digital-to-analog converter bus DAC_BUS, first data selector BUFIN, second data selector SNSCOM, third data selector FRCCOM, fourth data selector MUX1, buffer BUF, first voltage VDDP, second voltage VAREF, analog comparator input terminal SNSIN, signal SNSIN_5V from the analog circuit module in the 5V voltage domain, signal SNSIN_1.8V from the analog circuit module in the 1.8V voltage domain, output signal CMP_O, signal buf_o after passing through buffer BUF, port FRCOUT_5V for accessing the analog circuit module in the 5V voltage domain, port FRCOUT_1.8V for accessing the analog circuit module in the 1.8V voltage domain, first channel multiplexer ports PCH1~PCH3, second channel multiplexer ports NCH1-NCH3, analog-to-digital converter signal interface FRCCOMMON TO ADC. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0019] The implementation details of the technical solution of the embodiment of the present application are described in detail below.

[0020] Figure 1~Figure 4 The schematic diagrams of analog comparators with different structures are shown respectively, wherein an analog test bus is added to the analog comparator, so that the analog comparator can support multiple test functions and improve the test efficiency of the analog circuit module. Figure 1~Figure 4 In the embodiments, various components of the analog comparator are described in detail.

[0021] In one embodiment, reference Figure 1 The schematic diagram of the structure of the analog comparator shown in the figure includes an analog test bus (ATB, Analog Test Bus), a comparator CMP, a first signal interface SNSCE PAD, a second signal interface FORCE PAD and an analog-to-digital converter signal interface SNSCOMMON TO ADC. The analog test bus is used to test and verify the architecture of the analog circuit. It provides a shared signal transmission channel for transmitting analog signals in the circuit for testing and verification.

[0022] The analog test bus in the analog comparator includes a sensing bus SNS_BUS. The sensing bus SNS_BUS is an important component of the analog test bus, which is responsible for leading the analog signal to be tested from the analog circuit module to be tested and passing it to the test port. Among them, the analog circuit module to be tested refers to an analog integrated circuit whose function or performance needs to be verified during the test process, and the analog signal to be tested refers to the analog electrical signal output by the analog circuit module to be tested during the test process that needs to be monitored and analyzed.

[0023] In this embodiment, the analog circuit module to be tested is connected to the analog comparator input terminal SNSIN, so that the analog signal to be tested is input to the analog comparator. Figure 1 As shown, the analog comparator input terminal SNSIN is essentially a two-choice switch, which supports the access of signals from analog circuit modules in different voltage domains, including the signal SNSIN_5V from the analog circuit module in the 5V voltage domain and the signal SNSIN_1.8V from the analog circuit module in the 1.8V voltage domain. The analog comparator can select one of the signals at the analog comparator input terminal SNSIN as the input signal of the analog comparator, that is, the analog signal to be measured.

[0024] The sensing bus SNS_BUS is connected to the input terminal SNSIN of the analog comparator, so that the analog signal to be tested is transmitted to the first signal interface SNSCE PAD or the analog-to-digital converter signal interface SNSCOMMON TO ADC for testing through the sensing bus SNS_BUS. Among them, the first signal interface SNSCE PAD is mainly used to sense and monitor analog signals, and is usually directly connected to a test device (such as an oscilloscope, a signal analyzer, etc.) as a sensing pin of the test device. The first signal interface SNSCE PAD receives the analog signal to be tested transmitted through the sensing bus SNS_BUS, thereby transmitting the analog signal to be tested to the connected test device, so that the test device can monitor the analog signal to be detected on the first signal interface SNSCE PAD in real time. The analog-to-digital converter signal interface SNSCOMMON TO ADC is a data interface on the analog-to-digital converter, which can convert the analog signal to be tested into a digital signal, test and analyze the digital signal to evaluate the characteristics, performance or other parameters of the signal.

[0025] Among them, this test process is a perception test (SENSE test), which monitors the output signal of the analog circuit module in real time, measures the amplitude, frequency, phase and other parameters of the output signal, and evaluates whether the performance of the analog circuit module meets the design requirements. In actual applications, the analog circuit module to be tested is equipped with a perception port for perception testing. The perception port is connected to the analog comparator input terminal SNSIN to transmit the analog signal to be tested output by the analog circuit module to the analog comparator.

[0026] The second signal interface FORCE PAD configured by the analog comparator is an input interface that can be connected to an external signal source (such as a signal generator), receive an externally generated drive signal (such as a voltage or current signal), and then pass the received drive signal to the analog circuit module to be tested. Among them, this process is a drive test (FORCE test), which is mainly used to verify the function and performance of the chip under specific input conditions. By applying a known input signal (i.e., a drive signal) to the analog circuit module to be tested and observing its output response, the chip can be evaluated.

[0027] In practical applications, the analog circuit module to be tested is configured with a drive port for driving test, and the drive port is used to receive an external input drive signal to drive the analog circuit module to be tested. Here, a third signal interface (such as Figure 4The drive port of the analog circuit module to be tested is connected to the third signal interface FRCOUT, so that the drive signal can be applied to the analog circuit module to be tested through the third signal interface FRCOUT. At this time, the analog signal to be tested input by the analog circuit module to be tested is output under the drive of the drive signal, so that the drive test of the analog circuit module to be tested is realized by testing the analog signal to be tested.

[0028] In practical applications, the third signal interface FRCOUT can be a data selector, and the analog circuit module to be detected is connected to the second signal interface FORCE PAD through the third signal interface FRCOUT. Among them, the third signal interface FRCOUT supports analog circuit modules connected to different voltage domains, including analog circuit modules supporting 5V voltage domain and analog circuit modules supporting 1.8V.

[0029] The analog comparator also includes a comparator CMP. The main function of the comparator CMP is to compare the input signal with the reference voltage and generate an output signal CMP_O according to the comparison result. The output signal CMP_O is usually used to indicate which output signal is higher or meets specific conditions, so as to effectively monitor the performance and function of the chip under test. Among them, the input signal of the comparator CMP can be an analog signal to be tested from the analog circuit module to be tested. In practical applications, the comparator CMP is a rail-to-rail comparator, which can perform effective comparisons over the entire range of the input signal (from the lowest voltage to the highest voltage of the power supply), which means that it can handle very small signals and signals close to the power supply voltage.

[0030] It should be noted that during the operation of the analog comparator, the sensing bus SNS_BUS and the first signal interface SNSCE PAD are responsible for the acquisition and testing of the analog signal to be tested, and the second signal interface FORCE PAD is responsible for applying the external drive signal to the analog circuit module to be tested. The two signal flows are independent of each other, so the application of the external drive signal will not affect the acquisition and testing of the analog signal to be tested, so that the sensing test and the drive input are independent of each other and can work at the same time, thereby achieving the purpose of saving test time and reducing test costs.

[0031] In one embodiment, both input terminals of the comparator CMP support multi-channel input, such as Figure 2 As shown, in Figure 2 The comparator CMP in the embodiment supports four-channel input. The multi-channel input of the comparator CMP is realized through a multiplexer, wherein the first input terminal of the comparator CMP is connected to the first channel multiplexer PMUX, and the second input terminal of the comparator CMP is connected to the second channel multiplexer NMUX.

[0032] Among them, one port of the first channel multiplexer PMUX is connected to the sensing bus SNS_BUS, which is used to receive the analog signal to be tested from the analog circuit module to be tested, so that the analog signal to be tested can be selected and passed to the comparator CMP for comparison. The remaining ports (PCH1, PCH2, PCH3) of the first channel multiplexer PMUX can be used to access different signal sources (such as external analog signals). Similarly, one port of the second channel multiplexer NMUX is connected to the second signal interface FORCE PAD, which enables the external drive signal to be selected and passed to the comparator CMP. The remaining ports (NCH1, NCH2, NCH3) of the second channel multiplexer NMUX can also be connected to different signal sources.

[0033] In practical applications, the first channel multiplexer PMUX and the second channel multiplexer NMUX select one of the channels as output and pass it to the comparator CMP, so as to compare the signal from the first channel multiplexer PMUX with the signal from the second channel multiplexer NMUX to generate a final comparison result.

[0034] In one embodiment, it is understood that the main function of the comparator CMP is to compare two input signals and output a high or low signal according to the comparison result. In order to achieve this function, the comparator CMP needs a reference voltage as a reference for comparison. The first channel multiplexer PMUX can access multiple signal sources, which may include a reference voltage, that is, the reference voltage of the comparator CMP can be input through the first channel multiplexer PMUX, for example, the reference voltage is input to the comparator CMP through PCH1, PCH2 or PCH3 of the first channel multiplexer PMUX. Similarly, the second channel multiplexer NMUX can access multiple signal sources, which may include a reference voltage, so that the reference voltage of the comparator CMP can also be input through the second channel multiplexer NMUX, for example, the reference voltage is input to the comparator CMP through NCH1, NCH2 or NC3 of the second channel multiplexer NMUX.

[0035] In practical applications, if the first channel multiplexer PMUX selects the analog signal to be measured, then this signal will be input as one end of the comparator CMP. In this case, the second channel multiplexer NMUX can be used to input a reference voltage to the other end of the comparator CMP.

[0036] In one embodiment, the reference voltage of the comparator CMP can also be input through the first signal interface SNSCE PAD or the second signal interface FORCE PAD. The first signal interface SNSCE PAD is usually used to connect a detection device or other signal sources. If the first signal interface SNSCE PAD is connected to a stable voltage source, then the first signal interface SNSCE PAD can be used as the input of the reference voltage of the comparator CMP.

[0037] The second signal interface FORCE PAD is usually used to receive an externally applied signal for testing or calibration. If the second signal interface FORCE PAD is connected to a stable voltage signal, the second signal interface FORCE PAD can be used as the input of the reference voltage of the comparator CMP. In practical applications, if a reference voltage is input to the comparator CMP from the first signal interface SNSCE PAD, the reference signal can be input to the comparator CMP via the first channel multiplexer PMUX, and the signal for comparison with the reference voltage is input to the comparator CMP by the second channel multiplexer NMUX; if a reference signal is input to the comparator CMP from the second signal interface FORCE PAD, the reference signal can be input to the comparator CMP via the second channel multiplexer NMUX, and the signal for comparison with the reference voltage is input to the comparator CMP by the first channel multiplexer PMUX.

[0038] In one embodiment, the analog comparator further includes a digital-to-analog converter RDAC, which is an electronic component used to generate an adjustable voltage or current, and is generally composed of a plurality of resistor networks. These resistors can be selected and adjusted by digital signals to change the output voltage or current.

[0039] Here, in order to connect the digital-to-analog converter RDAC with other components in the analog comparator, a digital-to-analog converter bus DAC_BUS, a first data selector BUFIN, a second data selector SNSCOM, a third data selector FRCCOM and a buffer BUF are also configured. Specifically, Figure 3 As shown, Figure 3 The connection diagram of the digital-to-analog converter is shown. The digital-to-analog converter RDAC and the analog signal to be measured are respectively connected to the first data selector BUFIN, and the first data selector BUFIN is connected to the input end of the buffer BUF. Among them, the first data selector BUFIN is a two-choice switch module, which is used to select the output signal of the digital-to-analog converter RDAC or the analog signal to be measured to be input to the buffer BUF, so that the signal is buffered by the buffer BUF to improve the driving ability and stability of the signal and prevent the signal from being interfered or attenuated during the transmission process.

[0040] The output end of the buffer BUF is connected to the second data selector SNSCOM. At the same time, the analog signal to be measured is connected to the second data selector SNSCOM via the sensing bus SNS_BUS, and the second data selector SNSCOM is connected to the first input end of the comparator CMP. The second data selector SNSCOM is a two-choose-one switch module that can select the signal of one of the two channels. Here, the second data selector SNSCOM can select the analog signal to be measured, and can also select the signal buf_o after passing through the buffer BUF, so that the selected signal can be transmitted to the comparator CMP.

[0041] The output end of the buffer BUF is also connected to the third data selector FRCCOM, and the digital-to-analog converter RDAC is also connected to the third data selector FRCCOM via the digital-to-analog converter bus DAC_BUS, and the third data selector FRCCOM is connected to the second input end of the comparator CMP. Among them, the third data selector FRCCOM is a two-choose-one switch module, which can select the signal of one of the two channels. Here, the third data selector FRCCOM can select the output signal of the digital-to-analog converter RDAC, and can also select the signal buf_o after passing through the buffer BUF, so that the selected signal can be transmitted to the comparator CMP.

[0042] Based on this, the output signal of the digital-to-analog converter RDAC can be input into the comparator CMP through the connection relationship between different components and used as a reference voltage. Figure 3 As shown in the figure, the reference signal output by the digital-to-analog converter RDAC has three different signal transmission paths, namely: (1) The output signal of the digital-to-analog converter RDAC is transmitted to the third data selector FRCCOM through the digital-to-analog converter bus DAC_BUS, and then input to the comparator CMP through the second channel multiplexer NMUX to provide a reference; (2) The output signal of the digital-to-analog converter RDAC passes through the first data selector BUFIN, the buffer BUF, the third data selector FRCCOM in sequence, and finally inputs into the comparator CMP through the second channel multiplexer NMUX to provide a reference; (3) The output signal of the digital-to-analog converter RDAC passes through the first data selector BUFIN, the buffer BUF, the second data selector SNSCOM in sequence, and then is input to the comparator CMP through the first channel multiplexer PMUX to provide a reference.

[0043] It should be noted that the reference Figure 2 and Figure 3If the first input port of the comparator CMP inputs a reference voltage, wherein the reference voltage can be input by the first signal interface SNSCE PAD, the digital-to-analog converter RDAC or the first channel multiplexer PMUX, then the signal for comparison with the reference voltage is input to the second input port of the comparator CMP through the second channel multiplexer NMUX. The signal input to the second channel multiplexer NMUX can be an external analog signal, that is, input to the comparator CMP from NCH1, NCH2 or NCH3 in the second channel multiplexer NMUX. In addition, the signal input to the second channel multiplexer NMUX can also be an analog signal to be tested input to the analog comparator by the analog circuit module to be tested, and the analog signal to be tested is input to the comparator CMP from the second channel multiplexer NMUX via the first data selector BUFIN, the buffer BUF and the third data selector FRCCOM.

[0044] If the second input port of the comparator CMP inputs a reference voltage, wherein the reference voltage can be input by the second signal interface FORCE PAD, the digital-to-analog converter RDAC or the second channel multiplexer NMUX, then the signal for comparison with the reference voltage is input to the first input port of the comparator CMP through the first channel multiplexer PMUX. The signal input to the first channel multiplexer PMUX can be an external analog signal, that is, PCH1, PCH2 or PCH3 of the first channel multiplexer PMUX inputs the external analog signal into the comparator CMP. In addition, the signal input to the first channel multiplexer PMUX can also be an analog signal to be tested input to the analog comparator by the analog circuit module to be tested, and the analog signal to be tested is transmitted to the second signal selector via the sensing bus SNS_BUS, and then input to the comparator CMP through the first channel multiplexer PMUX.

[0045] In practical applications, reference Figure 3 If the analog signal to be measured is output through the third data selector FRCCOM, the third data selector FRCCOM can also send the analog signal to be measured to the analog-to-digital converter signal interface FRCCOMMON TO ADC for measurement, wherein the analog-to-digital converter signal interface FRCCOMMON TO ADC is the port connecting the analog-to-digital converter and the third data selector FRCCOM.

[0046] In one embodiment, Figure 4As shown, the analog comparator also includes a third signal interface FRCOUT, which is connected to the third data selector FRCCOM. Based on this, other analog circuit modules can be connected to the third signal interface FRCOUT, so that the output signal of the digital-to-analog converter RDAC can pass through the digital-to-analog converter bus DAC_BUS, and through the third data selector FRCCOM, the output value is connected to the analog circuit module of the third signal interface FRCOUT, thereby providing a reference voltage for the analog circuit module connected to the third signal interface FRCOUT.

[0047] In practical applications, the third signal interface FRCOUT can be a two-choice switch. The third signal interface FRCOUT includes an FRCOUT_5V port and an FRCOUT_1.8V port, which can support the access of analog circuit modules in two different voltage domains, including an analog circuit module in a 1.8V voltage domain and an analog circuit module in a 5V voltage domain. Figure 4 As shown, the third signal interface FRCOUT is also connected to the second signal interface FORCE PAD, so that the third data selector FRCCOM can also output the driving signal input from the second signal interface FORCE PAD to the analog circuit module in the 5V voltage domain connected to the third signal interface FRCOUT, or to the analog circuit module in the 1.8V voltage domain connected to the third signal interface FRCOUT.

[0048] In one embodiment, reference Figure 3~Figure 4 , the digital-to-analog converter RDAC is connected to the first voltage VDDP generated by the internal circuit and the second voltage VAREF generated by the external circuit. The first voltage VDDP may be a user-defined voltage or a signal generated by an external device, which is usually used in specific application scenarios, such as external calibration or testing. The second voltage VAREF is an additional reference or input provided.

[0049] Based on this, the first voltage VDDP and the second voltage VAREF can both be used as input voltages of the digital-to-analog converter RDAC, and the digital-to-analog converter RDAC can select the first voltage VDDP or the second voltage VAREF as the reference voltage provided by the digital-to-analog converter RDAC for the comparator CMP or the analog circuit module connected to the third signal interface FRCOUT.

[0050] In practical applications, reference Figure 3~Figure 4, the digital-to-analog converter RDAC can be connected to the first voltage VDDP and the second voltage VAREF respectively through a fourth data selector MUX1. The fourth data selector MUX1 is essentially a two-to-one switch, which can select to connect the first voltage VDDP or the second voltage VAREF. For example, when the selection signal is 0, the fourth data selector MUX1 connects the first voltage VDDP; when the selection signal is 1, the fourth data selector MUX1 connects the second voltage VAREF. Thus, the digital-to-analog converter generates an adjustable reference voltage according to the input voltage and the digital control signal, and outputs it to the outside.

[0051] In one embodiment, an analog comparator including a digital-to-analog converter RDAC can support current testing of an analog circuit module to be tested. The analog circuit module to be tested can convert a current signal to be tested into a voltage signal to be tested through the digital-to-analog converter RDAC, and then send the converted voltage signal to be tested to the first signal interface SNSCE PAD or the analog-to-digital converter signal interface SNSCOMMON TO ADC, thereby achieving the purpose of measuring current.

[0052] In practical applications, the digital-to-analog converter RDAC adjusts its output resistance value through digital control. , the input current signal can be converted into a corresponding voltage signal. Here, the digital code of the digital-to-analog converter RDAC is pre-set to determine its output resistance value This setting can be completed through the digital control interface to ensure that the digital-to-analog converter RDAC works in a predetermined resistance state. Based on this, the voltage value of the converted voltage signal is obtained through the first signal interface SNSCE PAD or the analog-to-digital converter signal interface SNSCOMMON TO ADC Then the current value of the current signal to be measured is for: .

[0053] It should be noted that since the internal parasitic capacitance of the digital-to-analog converter RDAC is much smaller than the capacitance of the chip's external wiring and instruments, this means that the measurement voltage settling time inside the digital-to-analog converter RDAC is relatively short and can quickly respond to changes in the input signal. When performing multiple sets of current tests, using the resistance of the digital-to-analog converter RDAC to perform a voltage strategy on the analog-to-digital converter can significantly reduce the test time. This is because the response speed of the internal measurement is faster than the measurement speed of the external instrument, avoiding the delay that may occur when using an external instrument. In addition, through the adjustable characteristics of the digital-to-analog converter RDAC, multiple sets of current tests can be easily performed on the same test platform without changing the hardware.

[0054] In one embodiment, the current signal to be measured is connected from the third signal interface FRCOUT, and the current signal to be measured flows through the third data selector FRCCOM, and the third data selector FRCCOM transmits the current signal to be measured to the digital-to-analog converter RDAC, so that the digital-to-analog converter RDAC converts the current signal to be measured into a voltage signal to be measured. The converted voltage signal to be measured passes through the first data selector BUFIN and enters the buffer BUF, and then transmits the voltage signal to be measured to the first signal interface SNSCE PAD or the analog-to-digital converter signal interface SNSCOMMON TO ADC through the second data selector SNSCOM for voltage measurement.

[0055] In the above embodiment, an analog test bus is added to the analog comparator, and the analog signal to be tested of the analog circuit module to be tested is transmitted to the first signal interface or the analog-to-digital converter signal interface for testing through the perception bus. On this basis, the analog comparator also includes a second signal interface for receiving an external input drive signal and transmitting the drive signal to the analog circuit module to be tested. In addition, the analog comparator also includes a comparator that can compare the input signal with a reference voltage. In the analog comparator, the perception test and the drive signal input are independent of each other and can work at the same time, thereby saving test time and reducing test costs.

[0056] In one embodiment, a chip is further provided, which integrates the above analog comparator.

[0057] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0058] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0059] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An analog comparator, characterized in that: It includes an analog test bus, a comparator, a first signal interface, a second signal interface and an analog-to-digital converter signal interface; the analog test bus includes a sensing bus, which is used to transmit the analog signal to be tested of the analog circuit module to be tested to the first signal interface or the analog-to-digital converter signal interface for testing; The second signal interface is used to receive an external driving signal and transmit the driving signal to the analog circuit module to be tested; The comparator is used to compare an input signal with a reference voltage and output a comparison result; the input signal includes the analog signal to be measured.

2. The analog comparator according to claim 1, characterized in that: The first input end of the comparator is connected to the first channel multiplexer, and the second input end of the comparator is connected to the second channel multiplexer; the input signal of the comparator is input through the first channel multiplexer or the second channel multiplexer; wherein, One port in the first channel multiplexer is connected to the sensing bus; one port in the second channel multiplexer is connected to the second signal interface; and the remaining ports in the first channel multiplexer and the second channel multiplexer are used to receive external analog signals.

3. The analog comparator according to claim 2, characterized in that: The reference voltage is input through the first channel multiplexer or the second channel multiplexer.

4. The analog comparator according to claim 2, characterized in that: The reference voltage is input through the first signal interface or the second signal interface.

5. The analog comparator according to claim 1 or 2, characterized in that: The analog test bus further includes a digital-to-analog converter bus, and the analog comparator further includes a digital-to-analog converter, a first data selector, a second data selector, a third data selector, and a buffer; The digital-to-analog converter and the analog signal to be measured are respectively connected to the first data selector; The first data selector is connected to an input terminal of the buffer; The output end of the buffer is connected to the second data selector and the third data selector respectively; The analog signal to be tested is connected to the second data selector via the sensing bus; The digital-to-analog converter is connected to the third data selector via the digital-to-analog converter bus; The second data selector is connected to the first input terminal of the comparator; the third data selector is connected to the second input terminal of the comparator; The digital-to-analog converter provides the reference voltage to the comparator through the second data selector or the third data selector.

6. The analog comparator according to claim 5, characterized in that: The analog comparator also includes a third signal interface; the third signal interface is connected to the third data selector; the digital-to-analog converter also provides a reference voltage to the analog circuit module connected to the third signal interface through the digital-to-analog converter bus.

7. The analog comparator according to claim 5, characterized in that: The digital-to-analog converter is respectively connected to a first voltage generated by an internal circuit and a second voltage generated by an external circuit, and is used to select the first voltage or the second voltage as the reference voltage.

8. The analog comparator according to claim 6, characterized in that: The analog signal to be tested is a current signal to be tested. The digital-to-analog converter converts the current signal to be tested into a voltage signal to be tested, and transmits the voltage signal to the first signal interface or the analog-to-digital converter signal interface for testing.

9. The analog comparator according to claim 8, characterized in that: The current signal to be measured is input from the third signal interface.

10. A chip, characterized in that: An analog comparator comprising the analog comparator as claimed in any one of claims 1 to 9.

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