Self-checking circuit

Abstract

The invention discloses a self-checking circuit, and belongs to the technical field of power electronics. The circuit comprises a miniaturized frequency source, a first amplification module and a second amplification module which are connected in sequence, under the condition that the input port of the miniaturized frequency source receives a reference signal and the control port of the miniaturized frequency source receives an adjusting signal, the miniaturized frequency source converts the reference signal into a radio frequency signal with the frequency or power corresponding to the adjusting signal; the first amplification module receives the radio frequency signal and outputs an amplified signal, and the second amplification module receives the amplified signal and outputs a self-checking signal. The circuit can be separated from a radio frequency signal and accurately control the power and the frequency of a self-checking signal.

Description

Technical Field

[0001] The present application belongs to the field of power electronics technology, and in particular, relates to a self-test circuit. Background Art

[0002] Self-checking technology is to automatically detect or monitor the function, performance and health status of a circuit or system by generating self-checking signals. Self-checking technology is widely used in modern electronic equipment and embedded systems, especially in equipment that requires high reliability (such as aerospace, communications, medical, industrial control and other fields). Through self-checking signals, the system can self-check and detect possible faults or abnormalities during operation, thereby improving the stability and reliability of the system and reducing maintenance costs.

[0003] Most of the existing self-test technologies are based on simpler hardware construction. The self-test signal exists only as a part of the overall structure and is integrated with the integrated RF signal. If there is a functional abnormality or device damage, the repair frequency is high and the disassembly and assembly are inconvenient. In order to ensure the quality and stability of the signal, only a self-test signal with a single frequency and fixed output power can be generated. The frequency band is narrow and the frequency is low. It can only simply check the system function and has limitations. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a self-test circuit that can be separated from the radio frequency signal and accurately control the power and frequency of the self-test signal.

[0005] In a first aspect, the present application provides a self-test circuit, the circuit comprising:

[0006] A miniaturized frequency source, a first amplification module, and a second amplification module connected in sequence;

[0007] When the input port of the miniaturized frequency source receives a reference signal and the control port of the miniaturized frequency source receives an adjustment signal, the miniaturized frequency source converts the reference signal into a radio frequency signal of a frequency or power corresponding to the adjustment signal, the first amplification module receives the radio frequency signal and outputs an amplified signal, and the second amplification module receives the amplified signal and outputs a self-test signal.

[0008] According to one embodiment of the present application, the miniaturized frequency source includes a connected frequency synthesizer and a phase-locked loop, the frequency synthesizer is used to call the phase-locked loop to adjust the reference signal into the radio frequency signal, and the phase-locked loop is used to compare the phases of the radio frequency signal and the reference signal to adjust the output frequency of the frequency synthesizer.

[0009] According to one embodiment of the present application, the model of the miniaturized frequency source is RJP020180D2, the control port includes an NSS pin, a MOSI pin and an SCK pin, the power supply terminal VCC1 of the miniaturized frequency source is connected to a 5V power supply, and the power supply terminal VCC1 is also grounded through parallel capacitors C30, C32 and C33, and the power supply terminal VCC2 of the miniaturized frequency source is connected to a 12V power supply, and the power supply terminal VCC2 is also grounded through parallel capacitors C36, C37 and C38.

[0010] According to one embodiment of the present application, the first amplification module includes a 5-digital controlled attenuator, a first operational amplifier and a first 3dB fixed attenuator connected in sequence, and the input port of the 5-digital controlled attenuator is connected to the output port of the miniaturized frequency source.

[0011] According to one embodiment of the present application, the model of the 5-digit CNC attenuator is IDA-0024-6B, the model of the first operational amplifier is HGC418H, the model of the first 3dB fixed attenuator is IFA-03, the output end of the first operational amplifier is connected to the first 3dB fixed attenuator through a capacitor C34, the output end of the first operational amplifier is connected to one end of the inductor L3, the other end of the inductor L3 is connected to an 8V power supply, and the other end of the inductor L3 is also grounded through a capacitor C31.

[0012] According to one embodiment of the present application, the first amplification module also includes a first driver chip, the input end of the first driver chip is connected to a 5-digital controlled attenuation control signal, the output of the first driver chip is connected to the driving port of the 5-digital controlled attenuator, the driving ports of the 5-digital controlled attenuator are pin C2_5, pin C3_5, pin C3_0, pin C4_5, pin C4_0, pin C5_5, pin C5_0, pin C6_5 and pin C6_0, the input end of the first driver chip is used to input the 5-digital controlled attenuation control signal, the 5-digital controlled attenuation control signal includes AT_V1 representing a 1dB attenuation position, AT_V2 representing a 2dB attenuation position, AT_V3 representing a 4dB attenuation position, AT_V4 representing an 8dB attenuation position, and AT_V5 representing a 16dB attenuation position.

[0013] According to one embodiment of the present application, the second amplification module includes a 3-digital controlled attenuator, a second operational amplifier, and a second 3dB fixed attenuator connected in sequence.

[0014] According to one embodiment of the present application, the model of the 3-digit CNC attenuator is IDA-0018-3A, the model of the second operational amplifier is HGC418H, the model of the second 3dB fixed attenuator is IFA-03, the output end of the second operational amplifier is connected to the second 3dB fixed attenuator through capacitor C43, the output end of the second operational amplifier is connected to one end of inductor L4, the other end of inductor L4 is connected to an 8V power supply, and the other end of inductor L4 is also grounded through capacitor C41.

[0015] According to one embodiment of the present application, the second amplification module also includes a second driver chip, the input end of the second driver chip is connected to the 3-dimensional digitally controlled attenuation control signal, the output of the second driver chip is connected to the driving port of the 3-dimensional digitally controlled attenuator, the driving ports of the 3-dimensional digitally controlled attenuator are pin 1A, pin 1B, pin 2B, pin 2A, pin 3B and pin 3A, the input end of the second driver chip is used to input the 3-dimensional digitally controlled attenuation control signal, the 3-dimensional digitally controlled attenuation control signal includes AT_1 representing a 20dB attenuation position, AT_2 representing a 5dB attenuation position, and AT_3 representing a 10dB attenuation position.

[0016] According to an embodiment of the present application, the circuit further includes a power switch circuit, one end of which is connected to a 12V power supply, and the other end of which is connected to a power supply terminal VCC2 of the miniaturized frequency source.

[0017] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application.

[0018] The self-test circuit provided by the present application has the following beneficial effects compared with the prior art:

[0019] (1) The self-test signal is sent through an independent self-test circuit, which is convenient for disassembly and maintenance. It can be separated from the radio frequency signal, accurately control the power and frequency of the self-test signal, adjust the power and frequency of the self-test signal, and the ultra-wide frequency band is controlled by the adjustment signal to output a self-test signal of any given frequency and power, which is convenient for checking the overall functions and indicators of the equipment, and for improving the overall functional indicators, and has strong applicability.

[0020] (2) Amplitude adjustment is achieved by the 5-digit CNC attenuator IDA-0024-6B and the 3-digit CNC attenuator IDA-0018-3A. Power adjustment is achieved through amplitude adjustment. In addition to frequency adjustment and amplitude adjustment, the self-test signal output power adjustment step is basically synchronized with the attenuation step of the two CNC attenuators to ensure that the step is ≤1dB. The signal power leaked during shutdown is mainly guaranteed by the isolation of the miniaturized frequency source itself and the closed design of the structural cavity, ensuring that no large signal is output from the output port of the self-test module when the power is cut off, so as to avoid interfering with the normal operation of the host module. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0022] Figure 1 It is one of the structural schematic diagrams of the self-test circuit provided in the embodiment of the present application;

[0023] Figure 2 This is the second structural diagram of the self-test circuit provided in the embodiment of the present application;

[0024] Figure 3 This is the third structural diagram of the self-test circuit provided in the embodiment of the present application.

[0025] Figure 4 It is a structural diagram of the self-test module provided in an embodiment of the present application. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0027] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0028] The self-test circuit provided in the embodiment of the present application is described in detail below through specific embodiments and application scenarios in conjunction with the accompanying drawings.

[0029] like Figure 1 and Figure 2 As shown, the self-test circuit includes a miniaturized frequency source, a first amplification module and a second amplification module connected in sequence;

[0030] When the input port of the miniaturized frequency source receives a reference signal and the control port of the miniaturized frequency source receives an adjustment signal, the miniaturized frequency source converts the reference signal into a radio frequency signal of a frequency or power corresponding to the adjustment signal, the first amplification module receives the radio frequency signal and outputs an amplified signal, and the second amplification module receives the amplified signal and outputs a self-test signal.

[0031] The reference signal may be a signal of known frequency provided by a stable signal source, such as a crystal oscillator, an external frequency source, etc., which serves as a reference frequency and is the basis for frequency conversion and adjustment.

[0032] The adjustment signal can be used to set the precise frequency of the output radio frequency signal, or to control its power output, and can be a power adjustment signal or a frequency adjustment signal.

[0033] For example, the frequency of the reference signal is 100 MHz, and the frequency of the radio frequency signal is 2 to 18 GHz.

[0034] In actual implementation, the miniaturized frequency source SOURCE1 adjusts the frequency or power of the radio frequency signal according to the change of the adjustment signal.

[0035] In the miniaturized frequency source SOURCE1, the frequency synthesizer uses technologies such as a phase-locked loop (PLL) or direct digital synthesis (DDS) to adjust the output frequency according to the input adjustment signal, and performs frequency modulation, mixing and other processes based on the reference signal to achieve frequency changes and ensure that the RF signal meets the power or frequency corresponding to the adjustment signal.

[0036] PLL synchronizes the RF signal with the reference signal by comparing their phases, and dynamically adjusts the output frequency of the frequency synthesizer, thereby ensuring that the frequency of the RF signal is stable and accurate.

[0037] The first amplification module performs a first amplification on the radio frequency signal to obtain an amplified signal to provide an amplification effect with high gain and low distortion.

[0038] The second amplification module amplifies the amplified signal for a second time to obtain a stronger self-test signal and output it. The signal after two amplifications may have higher power, which is suitable for driving downstream circuits or as a test and diagnosis signal, effectively avoiding distortion introduced by the higher gain of a single amplifier.

[0039] The power of the self-test signal can be -35 to +10dBm.

[0040] The self-test circuit provided in the embodiment of the present application realizes the sending of the self-test signal through an independent self-test circuit, is easy to disassemble and repair, can be separated from the radio frequency signal, accurately control the power and frequency of the self-test signal, adjust the power and frequency of the self-test signal, and the ultra-wide frequency band is controlled by the adjustment signal to output a self-test signal of any given frequency and power, which is convenient for checking the overall functions and indicators of the equipment, and is convenient for improving the overall functional indicators, and has strong applicability.

[0041] In some embodiments, the miniaturized frequency source includes a connected frequency synthesizer and a phase-locked loop, the frequency synthesizer is used to call the phase-locked loop to adjust the reference signal into the radio frequency signal, and the phase-locked loop is used to compare the phases of the radio frequency signal and the reference signal to adjust the output frequency of the frequency synthesizer.

[0042] The frequency synthesizer is responsible for converting the reference signal into the desired RF signal, using a phase-locked loop (PLL) to precisely adjust the frequency during the process.

[0043] In a miniaturized frequency source, the output frequency of a frequency synthesizer is controlled by a phase-locked loop (PLL), which is used to lock the phase relationship between the output frequency and a reference signal.

[0044] A frequency synthesizer can directly generate a signal of the desired frequency through digital signal processing using direct digital synthesis (DDS) technology, or it can mix a reference signal with a high-frequency local oscillator signal to generate a target frequency. It can also use multiplication or division technology to call a multiplier or divider to convert the reference signal into a target frequency.

[0045] A phase-locked loop (PLL) ensures that the output frequency of the frequency synthesizer maintains a certain phase relationship with the reference signal, thereby stabilizing the frequency.

[0046] Inside the phase-locked loop (PLL), the phase comparator compares the output signal of the frequency synthesizer with the reference signal, calculates the phase difference between the two, and converts it into a voltage signal RF signal as a phase error signal; the loop filter receives the error signal output by the phase comparator, filters it, removes noise, obtains a stable error signal, and further smoothes the signal; the voltage-controlled oscillator (VCO) adjusts its oscillation frequency according to the error signal output by the loop filter, so that the output frequency of the frequency synthesizer is closer to the frequency of the reference signal. The frequency of the VCO will be adjusted as the input control voltage changes, thereby adjusting the output frequency.

[0047] During the operation of the PLL, the phase comparator continuously monitors the phase difference between the reference signal and the output signal of the frequency synthesizer, and adjusts the operating frequency of the VCO through the loop filter. If the frequency of the reference signal changes, the phase-locked loop (PLL) will automatically adjust the output frequency of the VCO to keep it consistent with the phase of the reference signal, or lock it within a certain frequency range. When the phase-locked loop (PLL) completes phase locking, the frequency and phase relationship between the output signal of the frequency synthesizer and the reference signal remains stable, and the frequency of the output signal can be precisely controlled by adjusting the feedback loop of the phase-locked loop (PLL).

[0048] Through the feedback mechanism of the phase-locked loop, the frequency synthesizer will adjust the frequency of its output signal so that it is synchronized with the frequency of the reference signal to some extent. In this process, the phase-locked loop (PLL) can accurately control the output frequency of the frequency synthesizer. Even if the RF signal is in the high frequency range, it can still maintain high-precision stability. The frequency synthesizer will generate an RF signal whose frequency is determined by the reference signal after adjustment by the phase-locked loop (PLL).

[0049] The output frequency of the frequency synthesizer is stabilized under the regulation of the phase-locked loop (PLL), and the frequency of the output signal can be fine-tuned as needed.

[0050] The control signal can be used to further adjust the working state of a phase-locked loop (PLL), thereby adjusting the output frequency or phase of the frequency synthesizer.

[0051] The feedback mechanism of PLL ensures that the frequency of the RF signal always maintains a certain phase relationship with the reference signal, and can ensure the frequency stability of the output signal of the frequency synthesizer even in the case of external disturbances or temperature changes.

[0052] In this embodiment, the frequency synthesizer and the phase-locked loop work together to adjust the reference signal to a radio frequency signal, thereby ensuring the stability and high precision of the radio frequency signal.

[0053] In some embodiments, Figure 3 As shown, the model of the miniaturized frequency source is RJP020180D2, the control port includes an NSS pin, a MOSI pin and an SCK pin, a power supply terminal VCC1 of the miniaturized frequency source is connected to a 5V power supply, and the power supply terminal VCC1 is also grounded through a capacitor C30, a capacitor C32 and a capacitor C33 connected in parallel, and a power supply terminal VCC2 of the miniaturized frequency source is connected to a 12V power supply, and the power supply terminal VCC2 is also grounded through a capacitor C36, a capacitor C37 and a capacitor C38 connected in parallel.

[0054] The capacitors C30, C32 and C33 are 10 μF, 0.1 μF and 1 nF respectively; the capacitors C36, C37 and C38 are 1 nF, 0.1 μF and 0.1 μF respectively.

[0055] Among them, the input port of the miniaturized frequency source U10 is the REF pin, and the output port is the RFOUT pin. The reference signal is input to the input port of the miniaturized frequency source through the capacitor C35. The control port includes the NSS pin, the MOSI pin and the SCK pin, which correspond to LE, DATA and CLK, a total of three adjustment signals. LE represents the SPI enable signal, DATA represents the SPI data signal, and CLK represents the SPI clock signal.

[0056] In actual implementation, the 100MHz reference signal is input to the miniaturized frequency source through capacitor C35 and REF pin, capacitor C35 is 100pF, the control signal is input to the miniaturized frequency source through NSS pin, MOSI pin and SCK pin, and the RF signal is output to the first amplification module through RFOUT pin.

[0057] In some embodiments, the first amplification module includes a 5-digital controlled attenuator, a first operational amplifier, and a first 3dB fixed attenuator connected in sequence, and the input port of the 5-digital controlled attenuator is connected to the output port of the miniaturized frequency source.

[0058] The input port of the 5-bit CNC attenuator is pin IN, and the output port is pin OUT.

[0059] In some embodiments, the model of the 5-digit CNC attenuator is IDA-0024-6B, the model of the first operational amplifier is HGC418H, the model of the first 3dB fixed attenuator is IFA-03, the output end of the first operational amplifier is connected to the first 3dB fixed attenuator through capacitor C34, the output end of the first operational amplifier is connected to one end of the inductor L3, the other end of the inductor L3 is connected to an 8V power supply, and the other end of the inductor L3 is also grounded through capacitor C31.

[0060] The inductor L3 is 15nH and the capacitor C31 is 1nF.

[0061] In some embodiments, the first amplification module also includes a first driver chip, the input end of the first driver chip is connected to a 5-digital controlled attenuation control signal, the output of the first driver chip is connected to the driving port of the 5-digital controlled attenuator, the driving ports of the 5-digital controlled attenuator are pin C2_5, pin C3_5, pin C3_0, pin C4_5, pin C4_0, pin C5_5, pin C5_0, pin C6_5 and pin C6_0, the input end of the first driver chip is used to input the 5-digital controlled attenuation control signal, the 5-digital controlled attenuation control signal includes AT_V1 representing a 1dB attenuation position, AT_V2 representing a 2dB attenuation position, AT_V3 representing a 4dB attenuation position, AT_V4 representing an 8dB attenuation position, and AT_V5 representing a 16dB attenuation position.

[0062] The 5-digit digital controlled attenuator has 5 5-digit digital controlled attenuation control signals, AT_V1 represents 1dB attenuation position, AT_V2 represents 2dB attenuation position, AT_V3 represents 4dB attenuation position, AT_V4 represents 8dB attenuation position, and AT_V5 represents 16dB attenuation position;

[0063] In actual implementation, the first driver chip U11 is selected as MWC0003T, and the driving ports of the 5-pin CNC attenuator U6 are pin C2_5, pin C3_5, pin C3_0, pin C4_5, pin C4_0, pin C5_5, pin C5_0, pin C6_5 and pin C6_0. The 5-pin CNC attenuator U6 attenuates the RF signal;

[0064] The first operational amplifier U12 performs the first stage amplification on the attenuated RF signal and inputs it to the first 3dB fixed attenuator U9 through the pin OUT and the capacitor C34, where the capacitor C34 is 100pF;

[0065] The first 3dB fixed attenuator U9 attenuates the amplified RF signal to obtain an amplified signal (RE) and outputs it.

[0066] When the voltage at the input terminal VIN of the first driving chip U11 is 0V, at the output terminal of the second driving chip U13, A=-5V, B=0V; when the voltage at the input terminal VIN is 3.3V, A=0V, B=-5V.

[0067] For the driving port of the 5-pin digital controlled attenuator U6, pin C1_5 is always set to -5V, with 0.5dB attenuation at 0V;

[0068] Pin C2_5 has 1dB attenuation at 0V; pin C3_5 has 2dB attenuation at 0V, and pin C3_0 is -5V at this time; pin C4_5 has 4dB attenuation at 0V, and pin C4_0 is -5V at this time; pin C5_5 has 8dB attenuation at 0V, and pin C5_0 is -5V at this time; pin C6_5 has 16dB attenuation at 0V, and pin C6_0 is -5V at this time.

[0069] In this embodiment, attenuation is performed by a 5-bit digitally controlled attenuator and a first 3 dB fixed attenuator, thereby widening the adjustable range of the output power.

[0070] In some embodiments, the second amplification module includes a 3-dB digitally controlled attenuator, a second operational amplifier, and a second 3dB fixed attenuator connected in sequence.

[0071] The input port of the 3-bit CNC attenuator U15 is pin IN, and the output port is pin OUT.

[0072] In some embodiments, the model of the 3-D CNC attenuator is IDA-0018-3A, the model of the second operational amplifier is HGC418H, the model of the second 3dB fixed attenuator is IFA-03, the output end of the second operational amplifier is connected to the second 3dB fixed attenuator through capacitor C43, the output end of the second operational amplifier is connected to one end of inductor L4, the other end of inductor L4 is connected to an 8V power supply, and the other end of inductor L4 is also grounded through capacitor C41.

[0073] The inductor L4 is 15nH and the capacitor C41 is 1nF.

[0074] In some embodiments, the second amplification module also includes a second driver chip, the input end of the second driver chip is connected to the 3-dimensional digitally controlled attenuation control signal, the output of the second driver chip is connected to the driving port of the 3-dimensional digitally controlled attenuator, the driving ports of the 3-dimensional digitally controlled attenuator are pin 1A, pin 1B, pin 2B, pin 2A, pin 3B and pin 3A, the input end of the second driver chip is used to input the 3-dimensional digitally controlled attenuation control signal, the 3-dimensional digitally controlled attenuation control signal includes AT_1 representing a 20dB attenuation position, AT_2 representing a 5dB attenuation position, and AT_3 representing a 10dB attenuation position.

[0075] The 3-digit digital controlled attenuator has 3 3-digit digital controlled attenuation control signals, AT_1 represents 20dB attenuation position, AT_2 represents 5dB attenuation position, and AT_3 represents 10dB attenuation position.

[0076] In actual implementation, the second driver chip U13 is selected as MWC0003T, and the driving ports of the 3-digital controlled attenuator U15 are pin 1A, pin 1B, pin 2B, pin 2A, pin 3B and pin 3A. The 3-digital controlled attenuator U15 attenuates the amplified signal;

[0077] For the driving port of the 3-digital controlled attenuator U15, pin 1A attenuates 20 dB at -5 V, pin 2A attenuates 5 dB at -5 V, and pin 3A attenuates 10 dB at -5 V. Pin VEE of the second driving chip U13 is connected to the -5 V power supply and grounded through capacitor C40, which is 1 nF.

[0078] The second operational amplifier U16 performs a second stage amplification on the attenuated amplified signal and inputs it to the second 3dB fixed attenuator U14 through the pin OUT and the capacitor C43;

[0079] The second 3 dB fixed attenuator U14 attenuates the amplified signal to obtain a self-test signal and outputs it through the capacitor C44.

[0080] Capacitor C43 and capacitor C44 are both 100 pF.

[0081] When the voltage at the input terminal VIN of the second driving chip U13 is 0V, at the output terminal of the second driving chip U13, A=-5V, B=0V; when the voltage at the input terminal VIN is 3.3V, A=0V, B=-5V.

[0082] In this embodiment, attenuation is performed by a 3-dB digitally controlled attenuator and a second 3 dB fixed attenuator, thereby widening the adjustable range of the output power.

[0083] In some embodiments, the circuit further includes a power switch circuit, one end of which is connected to a 12V power supply, and the other end of which is connected to a power supply terminal VCC2 of the miniaturized frequency source.

[0084] In actual implementation, a switching element such as a MOS tube or a triode is provided in the power switch circuit, and the switching element is controlled to be turned on or off by a switch control signal to provide or cut off the DC working power 12V input of the 12V power supply terminal VCC2 of the miniaturized frequency source.

[0085] In addition, the self-test circuit may also be provided with a detection chip for detecting the voltage and current of the self-test circuit, generating a health signal and outputting it.

[0086] VCC2 is also grounded through capacitors C36, C37, and C38, respectively. Capacitor C36 is 1 nF, capacitor C37 is 0.1 μF, and capacitor C38 is 10 μF.

[0087] An embodiment is described below.

[0088] The function of the self-test circuit is mainly to provide a signal within the working frequency range of the equipment, which is used for calibration and inspection of the equipment. It has switching function, amplitude adjustment function and frequency adjustment function.

[0089] The output self-test signal meets the following requirements: frequency range 2 ~ 18GHz, power -35 ~ +10dBm, power adjustment step ≤ 1dB, shutdown leakage signal power <-55dBm.

[0090] A miniaturized frequency source RJP020180D2 with a high degree of control is selected as the core body. Through the SPI serial port communication protocol, the miniaturized frequency source is controlled by adjusting the signal to convert the input 100MHz reference signal into a 2-18GHz RF signal with a frequency step of 10MHz.

[0091] There are three types of adjustment signals for the miniaturized frequency source, LE represents the SPI enable signal, DATA represents the SPI data signal, and CLK represents the SPI clock signal.

[0092] Then two sets of digitally controlled attenuators and low-noise amplifiers with appropriate frequency ranges are added to broaden the adjustable range of output power;

[0093] Finally, two sets of 3dB fixed attenuators are added to balance the overall link gain to the appropriate position, and then the output power is adjusted to the range of -35 to +10dBm with the manual control digital attenuator.

[0094] There are 8 power control signals in total, among which, the 5-digit digital controlled attenuator has 5 power control signals, AT_V1 represents 1dB attenuation bit, AT_V2 represents 2dB attenuation bit, AT_V3 represents 4dB attenuation bit, AT_V4 represents 8dB attenuation bit, and AT_V5 represents 16dB attenuation bit;

[0095] The 3-bit digital controlled attenuator has 3 power control signals, AT_1 represents 20dB attenuation, AT_2 represents 5dB attenuation, and AT_3 represents 10dB attenuation.

[0096] The attenuation values ​​of the two digitally controlled attenuators corresponding to each frequency point and each output power value are recorded to form a data table, and the actual value of the output power corresponding to the theoretical output power is recorded. When needed, the attenuation value data in the table is called, and the two digitally controlled attenuators are controlled through the SPI serial port to accurately output the self-test signal power value.

[0097] See Table 1 below for attenuation value / output power data.

[0098] Table 1 Attenuation value / output power data table

[0099]

[0100] Amplitude adjustment is achieved by 5-digit CNC attenuator IDA-0024-6B and 3-digit CNC attenuator IDA-0018-3A. Power adjustment is achieved by amplitude adjustment. In addition to frequency adjustment and amplitude adjustment, the self-test signal output power adjustment step is basically synchronized with the attenuation step of the two CNC attenuators to ensure that the step is ≤1dB; and the signal power leaked when turned off is mainly guaranteed by the isolation of the miniaturized frequency source itself and the closed design of the structural cavity, ensuring that no large signal is output from the output port of the self-test module when the power is cut off, avoiding interference with the normal operation of the host module. The circuit chips of the RF part all use bare cores, which can effectively avoid signal crosstalk, improve the overall performance, and have good stability and high consistency.

[0101] like Figure 4 As shown, the self-test circuit in the present application can be integrated into a self-test module. Compared with the existing self-test technology that can only give a fixed frequency power, the self-test module can be used as a simple signal source to output a self-test signal of any frequency and power, thereby realizing the inspection of various functions of the equipment.

[0102] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0103] In the description of this application, "first feature" or "second feature" may include one or more of the features.

[0104] In the description of the present application, “plurality” means two or more.

[0105] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0106] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative 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 application. 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.

[0107] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A self-test circuit, characterized in that: It includes a miniaturized frequency source, a first amplification module and a second amplification module connected in sequence; When the input port of the miniaturized frequency source receives a reference signal and the control port of the miniaturized frequency source receives an adjustment signal, the miniaturized frequency source converts the reference signal into a radio frequency signal of a frequency or power corresponding to the adjustment signal, the first amplification module receives the radio frequency signal and outputs an amplified signal, and the second amplification module receives the amplified signal and outputs a self-test signal.

2. The self-test circuit according to claim 1, characterized in that: The miniaturized frequency source includes a connected frequency synthesizer and a phase-locked loop, the frequency synthesizer is used to call the phase-locked loop to adjust the reference signal into the radio frequency signal, and the phase-locked loop is used to compare the phases of the radio frequency signal and the reference signal to adjust the output frequency of the frequency synthesizer.

3. The self-test circuit according to claim 1, characterized in that: The model of the miniaturized frequency source is RJP020180D2, and the control port includes an NSS pin, a MOSI pin and an SCK pin. The power supply terminal VCC1 of the miniaturized frequency source is connected to a 5V power supply, and the power supply terminal VCC1 is also grounded through parallel capacitors C30, C32 and C33. The power supply terminal VCC2 of the miniaturized frequency source is connected to a 12V power supply, and the power supply terminal VCC2 is also grounded through parallel capacitors C36, C37 and C38.

4. The self-test circuit according to claim 1, characterized in that: The first amplification module includes a 5-digital controlled attenuator, a first operational amplifier and a first 3dB fixed attenuator connected in sequence, and the input port of the 5-digital controlled attenuator is connected to the output port of the miniaturized frequency source.

5. The self-test circuit according to claim 4, characterized in that: The model of the 5-digit numerically controlled attenuator is IDA-0024-6B, the model of the first operational amplifier is HGC418H, the model of the first 3dB fixed attenuator is IFA-03, the output end of the first operational amplifier is connected to the first 3dB fixed attenuator through capacitor C34, the output end of the first operational amplifier is connected to one end of the inductor L3, the other end of the inductor L3 is connected to an 8V power supply, and the other end of the inductor L3 is also grounded through capacitor C31.

6. The self-test circuit according to claim 5, characterized in that: The first amplification module also includes a first driver chip, the input end of the first driver chip is connected to a 5-digital controlled attenuation control signal, the output of the first driver chip is connected to the driving port of the 5-digital controlled attenuator, the driving ports of the 5-digital controlled attenuator are pin C2_5, pin C3_5, pin C3_0, pin C4_5, pin C4_0, pin C5_5, pin C5_0, pin C6_5 and pin C6_0, the input end of the first driver chip is used to input the 5-digital controlled attenuation control signal, the 5-digital controlled attenuation control signal includes AT_V1 representing a 1dB attenuation position, AT_V2 representing a 2dB attenuation position, AT_V3 representing a 4dB attenuation position, AT_V4 representing an 8dB attenuation position, and AT_V5 representing a 16dB attenuation position.

7. The self-test circuit according to claim 1, characterized in that: The second amplification module includes a 3-digital controlled attenuator, a second operational amplifier and a second 3dB fixed attenuator connected in sequence.

8. The self-test circuit according to claim 7, characterized in that: The model of the 3-dimensional numerically controlled attenuator is IDA-0018-3A, the model of the second operational amplifier is HGC418H, the model of the second 3dB fixed attenuator is IFA-03, the output end of the second operational amplifier is connected to the second 3dB fixed attenuator through capacitor C43, the output end of the second operational amplifier is connected to one end of inductor L4, the other end of inductor L4 is connected to an 8V power supply, and the other end of inductor L4 is also grounded through capacitor C41.

9. The self-test circuit according to claim 8, characterized in that: The second amplification module also includes a second driver chip, the input end of the second driver chip is connected to the 3-digital controlled attenuation control signal, the output of the second driver chip is connected to the driving port of the 3-digital controlled attenuator, the driving ports of the 3-digital controlled attenuator are pin 1A, pin 1B, pin 2B, pin 2A, pin 3B and pin 3A, the input end of the second driver chip is used to input the 3-digital controlled attenuation control signal, the 3-digital controlled attenuation control signal includes AT_1 representing a 20dB attenuation position, AT_2 representing a 5dB attenuation position, and AT_3 representing a 10dB attenuation position.

10. The self-test circuit according to claim 1, characterized in that: The circuit further comprises a power switch circuit, one end of which is connected to a 12V power supply, and the other end of which is connected to a power supply end VCC2 of the miniaturized frequency source.

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