Voltage-controlled oscillator applied to satellite-borne communication chip

Abstract

The invention belongs to the technical field of integrated circuits, and particularly relates to an anti-radiation voltage-controlled oscillator applied to a satellite-borne wireless communication system. The circuit structure comprises an anti-radiation voltage-controlled oscillator core circuit, a power detection circuit, an analog-to-digital converter and a control module. A control signal is input into the anti-radiation voltage-controlled oscillator core circuit, and two groups of voltage signals are generated and output to the power detection circuit; the power detection circuit processes the received voltage signal, outputs a processing result to the analog-to-digital converter, receives an instruction of the control module circuit, and outputs two groups of final voltage signals; the analog-to-digital converter converts a processing result output by the power detection circuit into a digital signal and outputs the digital signal to the control module; and the control module performs judgment according to the input digital signal, generates a control signal for controlling the working mode of the anti-radiation voltage-controlled oscillator core circuit, and generates a control signal for controlling the power detection circuit and the analog-to-digital converter. Wherein the core circuit architecture of the anti-radiation voltage-controlled oscillator is two cross-coupled voltage-controlled oscillators which share a capacitor array and an inductor, and the actually working oscillator branches are switched through a switch. By utilizing the structure, the probability of circuit failure caused by space irradiation can be obviously reduced, and the anti-irradiation performance and the stability of a satellite-borne wireless communication system are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of integrated circuits, and particularly relates to a voltage-controlled oscillator. Background Art

[0002] A voltage-controlled oscillator is an electronic oscillator that uses an external voltage to control the frequency. Its main functions are frequency adjustment and frequency stabilization. Voltage-controlled oscillators are widely used and play an important role in scenarios such as communication systems, clock generators, and signal processing.

[0003] Currently, voltage-controlled oscillators mainly include types such as inductor-capacitor voltage-controlled oscillators, quartz crystal voltage-controlled oscillators, Gilbert-Miller type voltage-controlled oscillators, and cross-coupled voltage-controlled oscillators. Among them, the cross-coupled voltage-controlled oscillator is a classic voltage-controlled oscillator. The cross-coupled transistor part has a negative resistance, which can cancel the parasitic effects of inductors and capacitors to achieve a better oscillation effect. The cross-coupled voltage-controlled oscillator has a simple structure and a fast response speed, and is suitable for wide-band applications.

[0004] With the progress of technology and the continuous expansion of the communication application field, more requirements have been put forward for voltage-controlled oscillators. In the aerospace field, the working environment of on-board chips is the space with strong radiation. The circuit modules in the chips are affected by radiation, having a higher failure probability and a shorter expected lifespan. Therefore, to improve the performance of on-board chips, it is necessary to effectively utilize chip anti-radiation technology to improve system stability and reliability. Summary of the Invention

[0005] The purpose of the present invention is to propose an anti-radiation voltage-controlled oscillator applied to on-board communication chips.

[0006] The circuit structure of the voltage-controlled oscillator proposed by the present invention includes: an anti-radiation voltage-controlled oscillator core circuit, a power detection circuit, an analog-to-digital converter, and a control module. The control signal is input to the anti-radiation voltage-controlled oscillator core circuit, generating two sets of voltage signals and outputting them to the power detection circuit; the power detection circuit processes the received voltage signals, outputs the processing results to the analog-to-digital converter, and receives the instructions of the control module circuit to output the final two sets of signals; the analog-to-digital converter converts the processing results output by the power detection circuit into digital signals and outputs them to the control module; the control module makes a judgment based on the input digital signals, generates a control signal for controlling the working mode of the anti-radiation voltage-controlled oscillator core circuit, and generates control signals for controlling the power detection circuit and the analog-to-digital converter.

[0007] In the present invention, the core circuit of the radiation-resistant voltage-controlled oscillator consists of a cross-coupled voltage-controlled oscillator with two shared capacitor arrays and inductors, and two single-pole double-throw numerically controlled switches; the capacitor array is composed of N groups of differential NMOS pairs with controlled source-drain terminal voltages, and its capacitance value changes with the change of the transistor drain terminal voltage; the two cross-coupled oscillators are backup to each other, and the output signals are controlled by the numerically controlled switches. Only one cross-coupled oscillator is used during actual normal operation; the numerically controlled switches will switch the actual working cross-coupled oscillator branch according to the signals of the control module in the system, thereby greatly improving the radiation resistance and stability of the system. Brief Description of the Drawings

[0008] Figure 1 It is a schematic structural diagram of the radiation-resistant voltage-controlled oscillator of the present invention.

[0009] Figure 2 It is a schematic diagram of the core circuit of the radiation-resistant voltage-controlled oscillator. Detailed Embodiment

[0010] The present invention will be described in more detail below with reference to the drawings. In each drawing, the same elements are denoted by similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale. In addition, some well-known parts may not be shown in the figures.

[0011] Many specific details of the present invention are described below, such as the structure, materials, dimensions, processing techniques and technologies of the devices, in order to understand the present invention more clearly. However, as those skilled in the art can understand, the present invention can be implemented without these specific details.

[0012] Figure 1 It shows a schematic structural diagram of the spaceborne radiation-resistant voltage-controlled oscillator of the present invention.

[0013] As Figure 1 shown, the spaceborne radiation-resistant voltage-controlled oscillator 100 in the present invention includes a radiation-resistant voltage-controlled oscillator core circuit 101, a power detection circuit 102, a control module 103, and an analog-to-digital converter 104. The radiation-resistant voltage-controlled oscillator core circuit 101 receives the control signal Ctrl<1:N + 2> output by the control module 103, and the output signals V op ’, V on ’ are transmitted to the power detection circuit 102, and the power detection circuit 102 outputs V op , V onAs the output signal of the entire voltage-controlled oscillator circuit. The power detection circuit 102 outputs pdout to the analog-to-digital converter 104, the analog-to-digital converter 104 outputs adout to the control module 103, and the control module 103 outputs Ctrl<1:N+2> to the radiation-hardened voltage-controlled oscillator core circuit 101, outputs ctrlN+3 to the power detection circuit 102, and outputs ctrlN+4 to the analog-to-digital converter 104.

[0014] Figure 2 Shows the schematic diagram of the radiation-hardened voltage-controlled oscillator core circuit in the present invention.

[0015] As Figure 2 shown, the radiation-hardened voltage-controlled oscillator core circuit includes a total of two inductors L1-L2, a capacitor array composed of N groups of differential NMOS pairs with source-drain terminal voltages controlled, two numerically controlled switches S1-S2, and two backup branches; the first branch includes cross-coupled differential pair transistors M1-M2 and a resistor R1; the second branch includes cross-coupled differential pair transistors M3-M4 and a resistor R2; when the radiation-hardened voltage-controlled oscillator core circuit receives a control signal to select the first branch, switch S1 is connected to the fixed terminal 1.1, and switch S2 is connected to the fixed terminal 2.1; when the radiation-hardened voltage-controlled oscillator core circuit receives a control signal to select the second branch, switch S1 is connected to the fixed terminal 1.2, and switch S2 is connected to the fixed terminal 2.2; the output signal V op ’ is connected to the moving terminal of switch S1, and the output signal V on ’ is connected to the moving terminal of switch S2. One end of inductor L1 is connected to the power supply VDD, and the other end is connected to the moving terminal of switch S1. One end of inductor L2 is connected to the power supply VDD, and the other end is connected to the moving terminal of switch S2. In the N groups of differential NMOS pairs with source-drain terminal voltages controlled, the drains of each pair of transistors are connected to each other, the sources are connected to each other, the source and the drain are connected to the corresponding controlled voltage bias, the gate of one transistor in each pair of transistors is connected to the moving terminal of switch S1, and the gate of the other transistor is connected to the moving terminal of switch S2. In the capacitor array, the controlled voltage bias values of the source and drain terminals of the same group of differential pair transistors are the same, the controlled voltage bias values of the source and drain terminals of different groups of differential pair transistors are independent, and the voltage bias values are VC1-VC N. In the first branch, the drain of transistor M1 is connected to the fixed end 1.1 of switch S1, the gate of M1 is connected to the fixed end 2.1 of switch S2, and the source of M1 is connected to resistor R1; the drain of transistor M2 is connected to the fixed end 2.1 of switch S2, the gate of M2 is connected to the fixed end 1.1 of switch S2, and the source of M2 is connected to resistor R1; one end of resistor R1 is connected to the sources of M1 and M2, and the other end is grounded. In the second branch, the drain of transistor M3 is connected to the fixed end 1.2 of switch S1, the gate of M3 is connected to the fixed end 2.2 of switch S2, and the source of M3 is connected to resistor R2; the drain of transistor M4 is connected to the fixed end 2.2 of switch S2, the gate of M4 is connected to the fixed end 1.2 of switch S1, and the source of M4 is connected to resistor R2; one end of resistor R2 is connected to the sources of M3 and M4, and the other end is grounded. There are two cores in this circuit structure. One is that the capacitor array is controlled by N groups of voltage signals, and the capacitance value can change with the change of N groups of voltage values, improving the stability and reliability of the system while realizing voltage-controlled oscillation; the other is that the control signal can change the states of switches S1 and S2, and the two branches in the core circuit are backup to each other and actually only one branch works, and the output end only outputs the signal of the actually working branch. When space radiation causes one of the working branches to fail, the control signal can change the switch state to make the actually working circuit switch to the circuit of the other branch, thus greatly improving the stability and reliability of the system.

Claims

1. A voltage-controlled oscillator applied to a spaceborne communication chip, the circuit structure of which includes: The core circuit of the radiation-resistant voltage-controlled oscillator, the power detection circuit, the analog-to-digital converter, and the control module. The control signal is input to the core circuit of the radiation-resistant voltage-controlled oscillator, generating two voltage signals and outputting them to the power detection circuit; the power detection circuit processes the received voltage signal, outputs the processing result to the analog-to-digital converter, and receives the instruction from the control module circuit to output the final two sets of voltage signals; The analog-to-digital converter converts the processing result output by the power detection circuit into a digital signal and outputs it to the control module; the control module makes a judgment based on the input digital signal, generates a control signal for controlling the working mode of the core circuit of the radiation-resistant voltage-controlled oscillator, and generates control signals for controlling the power detection circuit and the analog-to-digital converter.

2. The voltage-controlled oscillator applied to the spaceborne communication chip according to claim 1, wherein The core circuit of the radiation-resistant voltage-controlled oscillator consists of a cross-coupled voltage-controlled oscillator with two shared capacitor arrays and inductors, and two single-pole double-throw numerically controlled switches; the capacitor array is composed of N groups of differential NMOS pairs with the source-drain terminal voltage controlled, and its capacitance value will change with the change of the transistor source-drain terminal voltage; the two cross-coupled oscillators are backup to each other, and the output signal is controlled by the numerically controlled switch. Only one cross-coupled oscillator is used during actual normal operation; the numerically controlled switch will switch the actual working cross-coupled oscillator branch according to the signal of the control module in the system, thus greatly improving the radiation resistance and stability of the system.

3. The voltage-controlled oscillator applied to the spaceborne communication chip according to claim 2, wherein, The core circuit of the radiation-hardened voltage-controlled oscillator includes two inductors L1-L2, a capacitor array composed of N groups of differential NMOS pairs with source-drain terminal voltages controlled, two numerically controlled switches S1-S2, and two backup branches; the first branch includes cross-coupled differential pair transistors M1-M2 and a resistor R1; the second branch includes cross-coupled differential pair transistors M3-M4 and a resistor R2; when the core circuit of the radiation-hardened voltage-controlled oscillator receives a control signal to select the first branch, switch S1 is connected to the fixed terminal 1.1, and switch S2 is connected to the fixed terminal 2.1; when the core circuit of the radiation-hardened voltage-controlled oscillator receives a control signal to select the second branch, switch S1 is connected to the fixed terminal 1.2, and switch S2 is connected to the fixed terminal 2.2; the output signal V op ’ is connected to the moving terminal of switch S1, and the output signal V on ’ is connected to the moving terminal of switch S2. One end of inductor L1 is connected to the power supply VDD, and the other end is connected to the moving terminal of switch S1. One end of inductor L2 is connected to the power supply VDD, and the other end is connected to the moving terminal of switch S2. In the N groups of differential NMOS pairs with source-drain terminal voltages controlled, the drains of each pair of transistors are connected to each other, the sources are connected to each other, the source and the drain are connected to the corresponding controlled voltage bias, the gate of one transistor in each pair of transistors is connected to the moving terminal of switch S1, and the gate of the other transistor is connected to the moving terminal of switch S2. In the capacitor array, the controlled voltage bias values at the source and drain terminals of differential pair transistors in the same group are the same, and the controlled voltage bias values at the source and drain terminals of differential pair transistors in different groups are independent. The voltage bias values are VC1 - VC in sequence. N In the first branch, the drain of transistor M1 is connected to the fixed terminal 1.1 of switch S1, the gate of M1 is connected to the fixed terminal 2.1 of switch S2, and the source of M1 is connected to resistor R1; the drain of transistor M2 is connected to the fixed terminal 2.1 of switch S2, the gate of M2 is connected to the fixed terminal 1.1 of switch S2, and the source of M2 is connected to resistor R1; one end of resistor R1 is connected to the sources of M1 and M2, and the other end is grounded. In the second branch, the drain of transistor M3 is connected to the fixed terminal 1.2 of switch S1, the gate of M3 is connected to the fixed terminal 2.2 of switch S2, and the source of M3 is connected to resistor R2; the drain of transistor M4 is connected to the fixed terminal 2.2 of switch S2, the gate of M4 is connected to the fixed terminal 1.2 of switch S1, and the source of M4 is connected to resistor R2; one end of resistor R2 is connected to the sources of M3 and M4, and the other end is grounded. There are two cores in this circuit structure. One is that the capacitor array is controlled by N groups of voltage signals, and the capacitance value can change with the change of N groups of voltage values, improving the stability and reliability of the system while realizing voltage-controlled oscillation; the other is that the control signal can change the states of switches S1 and S2, and the two branches in the core circuit are backup to each other and actually only one branch works, and the output terminal only outputs the signal of the actually working branch. When space radiation causes one of the working branches to fail, the control signal can change the switch state to make the actually working circuit switch to the circuit of the other branch, thus greatly improving the stability and reliability of the system.

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