Tire pressure monitoring sensor circuit system and equipment based on NXP control chip

Abstract

The utility model relates to the technical field of tire pressure monitoring, and discloses a tire pressure monitoring sensor circuit system and equipment based on an NXP control chip. The tire pressure monitoring sensor circuit system comprises a control chip used for processing sensor data and controlling a communication function; the power supply module comprises a button battery and a power supply filter circuit, and the button battery provides 3.0 V working voltage and supplies power to the whole system through a VBAT node; the power supply filter circuit comprises a plurality of filter capacitors C12, C13 and C14 which are connected in parallel, one ends of the filter capacitors C12, C13 and C14 are connected with a VBAT node, and the other ends of the filter capacitors C12, C13 and C14 are grounded. According to the utility model, a plurality of functional modules such as the microprocessor, the radio frequency transceiver, the sensor interface and the power management module are integrated in a single control chip system through high integration, so that the circuit volume and the number of elements are obviously reduced, and the reliability and the stability of the system are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of tire pressure monitoring, in particular to the tire pressure monitoring sensor circuit system and equipment based on NXP control chip. BACKGROUND

[0002] NXP is the abbreviation of NXP Semiconductors N.V., a Dutch semiconductor company, and its Chinese name is NXP Semiconductor. For automotive control chips, it is called NXP control chip or NXP controller in the industry.

[0003] At present, with the rapid development of automotive electronics technology, the tire pressure monitoring system has become an important part of modern automobile safety configuration. The existing tire pressure monitoring system usually uses a sensor control chip based on MEMS technology to monitor the pressure, temperature and other parameters of the tire in real time through the sensor module installed inside the tire, and transmits the data to the vehicle receiver through wireless radio frequency.

[0004] In the prior art, the tire pressure sensor circuit is mostly designed with discrete components, including independent microcontrollers, radio frequency transceiver control chips, sensor interface circuits and power management modules, etc. Although this architecture can realize basic tire pressure monitoring functions, it has problems such as high circuit complexity, high power consumption, limited reliability, etc. Although the integration level is improved to some extent, there are still deficiencies in multi-sensor data fusion, anti-interference ability, environmental adaptability, etc. In addition, the existing tire pressure monitoring system still needs to be improved in terms of low-frequency wake-up sensitivity, radio frequency communication stability and working reliability in harsh environments, especially in the automotive environment with serious electromagnetic interference, the traditional design often cannot guarantee stable communication performance and data transmission accuracy.

[0005] The existing tire pressure monitoring technology mainly has the following technical problems: first, the circuit system designed with traditional discrete components is bulky, which is difficult to meet the installation requirements of the small space inside the tire. At the same time, due to the large number of components, the system reliability is reduced and the failure rate is increased. Second, the power consumption management is not intelligent enough to dynamically adjust the working mode according to the actual running state of the vehicle, resulting in a short battery life and the need to frequently replace the battery. Third, in terms of radio frequency communication, most systems only support single-band operation, lack flexibility, and the impedance matching network design is not optimized, resulting in limited communication distance and unstable signal quality. Fourth, the receiving sensitivity and anti-interference ability of the low-frequency wake-up circuit are insufficient, and it is easy to cause false triggering or failure to wake up in a complex electromagnetic environment.

[0006] Based on the above problems, it is urgent to design a tire pressure monitoring sensor circuit system and equipment based on NXP control chip to solve the above technical problems. The utility model discloses a content

[0007] The utility model discloses a purpose at providing based on NXP control chip's tire pressure monitoring sensor circuit system and equipment, through the high -degree integration with microprocessor, radio frequency transceiver, sensor interface and power management etc. multiple function module integration in single control chip system, significantly reduced the circuit volume and element quantity, improved the reliability and stability of system, aims at solving the problem among the prior art.

[0008] The utility model discloses a purpose at providing based on NXP control chip's tire pressure monitoring sensor circuit system, including:

[0009] Control chip is used to handle sensor data and control communication function;

[0010] Power module includes button cell and power filter circuit, and the button cell provides 3.0V working voltage, and through VBAT node is powered to whole system, and the power filter circuit contains multiple parallel filter capacitors C12, capacitor C13, capacitor C14, one end of filter capacitor C12, capacitor C13, capacitor C14 is connected VBAT node, and the other end is grounded;

[0011] Sensor module includes pressure sensor unit, temperature sensor unit and gravity acceleration sensor unit, is connected through connecting end 6, end 7, end 8 respectively, and with the corresponding pin of control chip is connected;

[0012] Radio frequency communication module includes high frequency transceiving unit and radio frequency matching network, and the high frequency transceiving unit is connected with control chip through connecting end 4, and the radio frequency matching network is composed of capacitor C5, capacitor C6, capacitor C8 and inductance L3, inductance L6, is connected between the RFOUT pin of control chip and radio frequency antenna interface TP2;

[0013] Low frequency receiving module includes low frequency receiving unit and LC resonant circuit, and the low frequency receiving unit is connected with control chip through connecting end 5, and the LC resonant circuit is composed of inductance L5, capacitor C7 and resistance R1, is connected between the LFA pin, LFB pin of control chip and low frequency antenna interface;

[0014] Clock circuit includes 26MHz crystal oscillator, and is connected with control chip through connecting end 3;

[0015] Test point is connected with control chip through connecting end 1.

[0016] Further, the power module further includes reset circuit and background debugging interface circuit;

[0017] The reset circuit includes resistance R3 and relevant circuit connected in the RESET node.

[0018] The background debugging interface circuit includes a resistor R2 and related circuits connected to the BKGD node;

[0019] The VREG pin of the control chip is connected to a stabilizing capacitor C11, forming an external compensation network of an internal stabilizer.

[0020] Further, the radio frequency communication module adopts a multi-stage impedance matching network structure, including:

[0021] The first-stage matching network is composed of an inductor L1 and capacitors C1 and C2, and is connected between the VBAT power supply and the radio frequency circuit;

[0022] The second-stage matching network is composed of capacitors C5, C6, and C8 and inductors L3 and L6, forming a π-type matching network, which accurately matches the output impedance of the control chip RFOUT and the antenna impedance.

[0023] Further, the low-frequency receiving module adopts a high-Q LC resonant circuit design; the inductor L5 adopts a high-precision inductor of 7.2 mH, the capacitor C7 adopts a low-temperature drift capacitor of 220 nF, and the resistor R1 adopts a current-limiting resistor of 47 KΩ, which together constitute a parallel resonant circuit with a Q value greater than 50.

[0024] Further, the sensor module adopts multi-sensor data fusion processing; the pressure sensor unit adopts a MEMS piezoresistive sensor with a measurement range of 0-1500 kPa; the temperature sensor unit adopts a semiconductor temperature sensor with a measurement range of -40-125°C; the gravity acceleration sensor unit adopts a three-axis MEMS accelerometer; and the control chip internally integrates a high-precision ADC and a digital filtering algorithm.

[0025] Further, the clock circuit adopts a 26 MHz base frequency crystal oscillator design; the crystal Y1 of the 26 MHz base frequency crystal oscillator adopts an AT-cut crystal with a load capacitor of 12 pF; and the external load capacitors C9 and C10 are NPO ceramic capacitors with an accuracy of ±5%.

[0026] Further, the tire pressure monitoring sensor circuit system further includes a hibernation low-power control unit connected to the control chip through a connection terminal 9.

[0027] The control chip has multiple power consumption modes built-in, including a normal working mode, a low-frequency monitoring mode, and a deep sleep mode; the system can automatically switch the power consumption mode according to the vehicle motion state detected by the acceleration sensor, the timer timeout, or the low-frequency wake-up signal.

[0028] Further, the radio frequency antenna interface TP2 is connected to the control chip RFOUT pin through a matching network composed of a capacitor C5 and an inductor L3; the LFA pin and the LFB pin connected with the low frequency antenna interface are connected to the control chip through an LC resonance circuit.

[0029] Further, the test point is connected with the control chip through a connection end 1, and can access the key signal node in the control chip; the control chip realizes online programming, data reading and function testing through BKGD and RESET pins, and is used for providing a background debugging mode.

[0030] Compared with the prior art, the tire pressure monitoring sensor circuit system and the device based on the NXP control chip have the following beneficial effects:

[0031] 1. By highly integrating a microprocessor, a radio frequency transceiver, a sensor interface and a power management and the like multiple functional modules in a single control chip system, the circuit volume and the component quantity are significantly reduced, the reliability and the stability of the system are improved, the multi-stage impedance matching network design and the dual-band radio frequency architecture ensure the efficient communication of the 315MHz / 433MHz frequency band, the signal transmission quality and the anti-interference ability are improved, the communication distance is prolonged, and the technical problem of unstable communication of the traditional tire pressure monitoring system in a complex electromagnetic environment is effectively solved.

[0032] 2. An intelligent power consumption management strategy is adopted, based on multi-sensor data fusion and motion state detection, the adaptive switching of a normal working mode, a low frequency monitoring mode and a deep sleep mode is realized, the standby current is reduced to below 5muA, the battery service life is greatly prolonged, the high Q value LC resonance circuit design makes the 125KHz low frequency wake-up sensitivity significantly improved, the signal isolation of the high frequency and the low frequency effectively reduces the intermodulation interference, in combination with the perfect background debugging interface and the self-checking function, the maintainability and the environmental adaptability of the system are greatly improved, and the long-term stable operation under harsh working conditions is ensured.

[0033] The tire pressure monitoring sensor circuit device based on the NXP control chip comprises a device body and a monitoring system. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 The utility model provides a structure schematic view of the tire pressure monitoring sensor circuit system based on the NXP control chip.

[0035] Figure 2 The utility model provides a circuit schematic view of the control chip in the tire pressure monitoring sensor circuit system based on the NXP control chip.

[0036] Figure 3The utility model provides a circuit schematic view of radio frequency antenna interface TP2 in the tire pressure monitoring sensor circuit system based on NXP control chip is provided for the utility model,

[0037] Figure 4 The utility model provides a circuit schematic view of radio frequency antenna interface TP1 in the tire pressure monitoring sensor circuit system based on NXP control chip is provided for the utility model,

[0038] Figure 5 The utility model provides a circuit schematic view of low frequency antenna interface in the tire pressure monitoring sensor circuit system based on NXP control chip is provided for the utility model,

[0039] Figure 6 The utility model provides a circuit schematic view of power module in the tire pressure monitoring sensor circuit system based on NXP control chip is provided for the utility model,

[0040] Figure 7 The utility model provides a circuit schematic view of background debugging interface circuit in the tire pressure monitoring sensor circuit system based on NXP control chip is provided for the utility model. DETAILED DESCRIPTION

[0041] In order to make the utility model's purpose, technical scheme and advantage more clearly clear, following combining with the attached drawing and example, this utility model carries out further detailed explanation.It should be understood that the specific example described here is only used to explain the utility model, and is not used to limit the utility model.

[0042] The implementation of the utility model is described in detail below in conjunction with specific examples.

[0043] The same or similar reference numerals in the drawings of the embodiment correspond to the same or similar components; in the description of the utility model, it should be understood that if the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right" etc. is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the utility model and simplifying the description, and not indicating or implying that the indicated device or element must have a particular orientation, structure and operation, therefore the positional relationship description term in the drawings is only used for example, and cannot be understood as the limitation of the utility model, for the ordinary skilled in the art, can understand the specific meaning of the above terms according to the specific situation.

[0044] Reference Figure 1As shown, the circuit system based on the NXP tire pressure sensor control chip includes: a control chip using an NTM8H1X5 control chip for processing sensor data and controlling communication functions; a power module including a button cell and a power filter circuit, the button cell providing a 3.0V working voltage, and the entire system is powered through a VBAT node; the power filter circuit includes a plurality of parallel filter capacitors C12, C13, and C14, one end of each of the filter capacitors C12, C13, and C14 being connected to the VBAT node and the other end being grounded; a sensor module including a pressure sensor unit, a temperature sensor unit, and a gravity acceleration sensor unit, each being connected to a corresponding pin of the control chip through a connection end 6, 7, and 8, respectively; a radio frequency communication module including a high-frequency transceiver unit and a radio frequency matching network, the high-frequency transceiver unit being connected to the control chip through a connection end 4 and supporting 315MHz and 433MHz dual-band operation; the radio frequency matching network is composed of capacitors C5, C6, C8, and inductors L3, L6, and is connected between the RFOUT pin of the control chip and a radio frequency antenna interface TP2; a low-frequency receiving module including a 125KHz low-frequency receiving unit and an LC resonant circuit, the low-frequency receiving unit being connected to the control chip through a connection end 5; the LC resonant circuit is composed of an inductor L5, a capacitor C7, and a resistor R1, and is connected between the LFA pin, the LFB pin of the control chip, and a low-frequency antenna interface; a clock circuit including a 26MHz crystal oscillator connected to the control chip through a connection end 3; a test point connected to the control chip through a connection end 1; by highly integrating a microprocessor, a radio frequency transceiver, a sensor interface, and a power management and other functional modules in a single control chip system, the circuit volume and the number of components are significantly reduced, and the reliability and stability of the system are improved.

[0045] In the present embodiment, the power module further includes a reset circuit and a background debugging interface circuit; the reset circuit includes a resistor R3 and related circuits connected to a RESET node; the background debugging interface circuit includes a resistor R2 and related circuits connected to a BKGD node; a VREG pin of the control chip is connected to a stabilizing capacitor C11 to form an external compensation network of an internal stabilizer, which is specifically described in Figures 6-7 The battery shown provides a 3.0V voltage, and the node labeled VBAT is the main power supply end; the capacitor C13 has one end connected to VBAT and the other end grounded, and functions to filter and stabilize the VBAT voltage; the resistors R2 and R3, each being 4.7KΩ, have one end commonly connected to VBAT, the other end of R2 being connected to the BKGD node, and the other end of R3 being connected to the RESET node, for voltage division or current limiting processing of related signals; the capacitor C12 has one end connected to VBAT and the other end grounded, for filtering the voltage input from VBAT to parts such as the control chip; and the capacitor C14 has one end connected to VBAT and the other end grounded, for further filtering and stabilizing the voltage.

[0046] In the embodiment, the radio frequency communication module adopts a multi-stage impedance matching network structure; the first stage matching network is composed of inductance L1 and capacitance C1 and capacitance C2, connected between VBAT power supply and radio frequency circuit; the second stage matching network is composed of capacitance C5, capacitance C6, capacitance C8 and inductance L3 and inductance L6, forming a π-type matching network, accurately matching the control chip RFOUT output impedance and antenna impedance.

[0047] In the embodiment, the low frequency receiving module adopts a high Q value LC resonant circuit design; inductance L5 adopts a high precision inductance of 7.2mH, capacitance C7 adopts a low temperature drift capacitance of 220nF, and resistance R1 adopts a current limiting resistance of 47KΩ, which together constitute a parallel resonant circuit with a Q value greater than 50, and the resonant frequency is accurately tuned at 125KHz.

[0048] In the embodiment, the sensor module adopts a multi-sensor data fusion processing technology; the pressure sensor unit adopts a MEMS piezoresistive sensor, with a measurement range of 0-1500kPa; the temperature sensor unit adopts a semiconductor temperature sensor, with a measurement range of -40-125℃; the gravity acceleration sensor unit adopts a three-axis MEMS accelerometer; the control chip internally integrates a high precision ADC and a digital filter algorithm;

[0049] Among them, the pressure sensor unit: connected with the control chip through the connection end 6, used for detecting the pressure signal, and transmitting the detected pressure related data to the control chip for processing;

[0050] The temperature sensor unit: connected with the control chip through the connection end 7, responsible for detecting the temperature signal, and transmitting the temperature data to the control chip for further operation;

[0051] The gravity acceleration sensor unit: used for measuring the acceleration of X axis and Z axis, connected with the control chip through the connection end 8, used for detecting the gravity acceleration related signal, and sending the collected acceleration data to the control chip.

[0052] In the embodiment, the clock circuit adopts a 26MHz base frequency crystal oscillator design; the crystal Y1 adopts an AT-cut crystal, with a load capacitance of 12pF; the external load capacitances C9 and C10 adopt NPO ceramic capacitors with an accuracy of ±5%; the 26MHz crystal oscillator: connected with the control chip through the connection end 3, provides a 26MHz clock signal for the control chip, which is the clock source for the normal operation of the control chip, and the crystal oscillator acts to cooperate with the internal circuit of the control chip to provide a 26MHz basic clock signal for the system; through the clock signal, the control chip can execute tasks according to the accurate time sequence, ensuring the normal operation of the device.

[0053] In this embodiment, a low-power sleep control unit is also included, connected to the control chip through connection terminal 9; the control chip has multiple power consumption modes, including normal operation mode, low-frequency monitoring mode and deep sleep mode; the system can automatically switch power consumption modes according to the vehicle motion state detected by the acceleration sensor, timer timeout or low-frequency wake-up signal, and the functions and working logic are as follows: to realize low-power function, the control chip has two states, sleep and wake-up, when the sensor is in sleep state, the power consumption is the lowest, at this time the sensor does not work, when the sensor is in wake-up state, the high and low frequency unit, pressure, temperature, acceleration and other units will work.

[0054] In this embodiment, the radio frequency antenna interface TP2 is connected to the control chip RFOUT pin through a matching network composed of capacitor C5 and inductor L3; the low-frequency antenna interface is connected to the corresponding pin of the control chip through an LC resonance circuit, the sensor receives 125KHz low frequency and sends 433MHz or 315Mhz high frequency, the automobile ECU sends low frequency and receives high frequency, so the sensor and the automobile ECU interact data through high and low frequencies.

[0055] In this embodiment, the test point is connected to the control chip through connection terminal 1, which can access the key signal nodes inside the control chip; the control chip provides a background debugging mode, which realizes online programming, data reading and function testing through BKGD and RESET pins, and is used to provide a burning program interface.

[0056] In this embodiment, the control chip integrates a microprocessor, a radio frequency transceiver, a sensor interface, a memory and a power management multiple function module inside; QFN packaging is adopted; the peripheral elements adopt 0402 or smaller size packaging; the entire circuit board adopts circular design and epoxy resin potting process.

[0057] This technical solution integrates multiple function modules such as microprocessor, radio frequency transceiver, sensor interface and power management in a single control chip system through high integration, significantly reduces the circuit volume and the number of elements, improves the reliability and stability of the system, the multi-stage impedance matching network design and the dual-band radio frequency architecture ensure the efficient communication of 315MHz / 433MHz frequency band, improve the signal transmission quality and anti-interference ability, at the same time, prolong the communication distance, effectively solve the technical problem of unstable communication of traditional tire pressure monitoring system in complex electromagnetic environment.

[0058] Referring to Figure 2 The control chip (NTM8H1X5) is connected to pins 1-6 (N.C.);

[0059] Pin 7 (PTI_A): connected to BKGD node;

[0060] Pin 8 (RESET_B): Connects to the RESET node;

[0061] Pin 9 (VDDA): Connects to VBAT, which provides power supply for the analog part of the control chip;

[0062] Pin 10 (VDD): Connects to VBAT, which provides power supply for the digital part of the control chip;

[0063] Pin 11 (VREG): Connects to capacitor C11, the other end of which is grounded. VREG is a pin related to the internal voltage regulator of the control chip, and C11 is used to stabilize the voltage of this pin;

[0064] Pin 12 (VREG): Same function as pin 11, also connects to capacitor C11, which is connected to C11 for voltage stabilization;

[0065] Pin 13 (PTB0): No external component is connected;

[0066] Pin 14 (PTA3): Connects to the relevant node through resistor R9 (0Ω);

[0067] Pin 15 (PTA2): Connects to the relevant node through resistor R8 (0Ω), R8 is reserved or not soldered;

[0068] Pin 16 (PTA1): Connects to the relevant node through resistor R7 (0Ω);

[0069] Pin 17 (RFGND): Grounded, providing a ground reference for the RF part;

[0070] Pin 18 (RFOUT): Outputs the RF signal, connected to the RF signal path;

[0071] Pins 25-27 (GND): All grounded, providing ground connection for the control chip;

[0072] Pin 28 (BKGD): Connects to the BKGD node;

[0073] Pin 29 (RESET): Connects to the RESET node.

[0074] Referring to Figure 3 Figure 1, the RF antenna interface TP2: receives or transmits RF signals, connected to the relevant pins of the control chip such as RFOUT through a matching network composed of capacitors C5 (15pF / 50V) and inductors L3 (1.8nH), to realize the transmission and matching of RF signals;

[0075] Capacitors C1 and C2: both are 100nF / 50V, one end connected to VBAT, the other end cooperates with inductor L1 (100nH) to form a filter or matching circuit related to RF, ensuring the quality of RF signals;

[0076] Capacitors C8, C6: 15pF / 50V, 18pF / 50V, respectively, constitute a radio frequency matching or filtering circuit with inductor L3 (47nH), connected to the RF signal path;

[0077] Crystal Y1 (26MHz): cooperates with capacitors C10 (12pF / 50V), C9 (12pF / 50V) to provide a clock signal for the control chip, the pin of Y1 is connected to the relevant clock input pin of the control chip.

[0078] Reference Figure 4 The radio frequency antenna interface TP1 is connected to the ground through capacitor C4 (2pF / 50V) and resistor R4 (0Ω), and is also associated with the circuit of the low frequency part (through a line connection) for the transmission of radio frequency signals and the like.

[0079] Referring to Figure 5 The low frequency antenna interface is connected to a circuit composed of resistor R1 (47KΩ), capacitor C7 (220nF / 50V), and inductor L5 (7.2mH), which is used for receiving or processing low frequency signals. The LFA pin and the LFB pin are connected to the control chip through a line to realize the interaction between the low frequency signal and the control chip.

[0080] The tire pressure monitoring sensor circuit device based on the NXP control chip comprises a device body and a monitoring system, and the monitoring system is the tire pressure monitoring sensor circuit system described above.

[0081] The technical solution adopts an intelligent power consumption management strategy, realizes adaptive switching of normal working mode, low frequency monitoring mode and deep sleep mode based on multi-sensor data fusion and motion state detection, reduces the standby current to below 5μA, greatly prolongs the service life of the battery, and simultaneously, the design of the high Q value LC resonant circuit significantly improves the 125KHz low frequency wake-up sensitivity, the signal isolation of high frequency and low frequency effectively reduces the intermodulation interference, in combination with a perfect background debugging interface and a self-checking function, the system maintainability and environmental adaptability are greatly improved, and long-term stable operation in harsh working conditions is ensured.

[0082] Overall, the circuit system realizes the functions of power supply, radio frequency signal processing, low frequency signal processing, and clock and control of the control chip through reasonable connection of various components, and provides hardware support for the system based on the NTM8H1X5 control chip.

[0083] In the embodiment, the entire operation process can be controlled by a computer, and the order of the steps can be realized through signal feedback by setting sensors. These are all conventional knowledge of automatic control, and will not be described one by one in the embodiment.

[0084] The above merely describes preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, and improvement within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. Tire pressure monitoring sensor circuitry based on NXP control chip, characterized in that, include: The control chip is used to process sensor data and control communication functions. The power module includes a button cell battery and a power filter circuit. The button cell battery provides a 3.0V operating voltage and supplies power to the entire system through the VBAT node. The power filter circuit includes multiple parallel filter capacitors C12, C13, and C14. One end of each filter capacitor C12, C13, and C14 is connected to the VBAT node, and the other end is grounded. The sensor module includes a pressure sensor unit, a temperature sensor unit, and a gravity acceleration sensor unit, which are connected to the corresponding pins of the control chip via connection terminals 6, 7, and 8, respectively. The radio frequency communication module includes a high-frequency transceiver unit and a radio frequency matching network. The high-frequency transceiver unit is connected to the control chip through connection terminal 4. The radio frequency matching network consists of capacitors C5, C6, and C8, and inductors L3 and L6, and is connected between the RFOUT pin of the control chip and the radio frequency antenna interface TP2. The low-frequency receiving module includes a low-frequency receiving unit and an LC resonant circuit. The low-frequency receiving unit is connected to the control chip via a connection terminal 5. The LC resonant circuit consists of an inductor L5, a capacitor C7, and a resistor R1, and is connected between the LFA pin, the LFB pin, and the low-frequency antenna interface of the control chip. The clock circuit, including a 26MHz crystal oscillator, is connected to the control chip via connection terminal 3; The test point is connected to the control chip via connection terminal 1.

2. The NXP control-chip-based tire pressure monitoring sensor circuitry of claim 1, wherein, The power module also includes a reset circuit and a background debugging interface circuit; The reset circuit includes resistor R3 and related circuitry connected to the RESET node; The background debugging interface circuit includes resistor R2 and related circuitry connected to the BKGD node. The VREG pin of the control chip is connected to the voltage regulator capacitor C11, forming an external compensation network for the internal voltage regulator.

3. The NXP control chip based tire pressure monitoring sensor circuitry of claim 2, wherein, The radio frequency communication module adopts a multi-level impedance matching network structure, including: The first-stage matching network consists of inductor L1 and capacitors C1 and C2, and is connected between the VBAT power supply and the RF circuit. The second-stage matching network consists of capacitors C5, C6, and C8, and inductors L3 and L6, forming a π-type matching network that precisely matches the RFOUT output impedance of the control chip with the antenna impedance.

4. The NXP control-chip-based tire pressure monitoring sensor circuitry of claim 3, wherein, The low-frequency receiving module adopts a high-Q-value LC resonant circuit design; the inductor L5 is a 7.2mH high-precision inductor, the capacitor C7 is a 220nF low-temperature drift capacitor, and the resistor R1 is a 47KΩ current-limiting resistor, which together form a parallel resonant circuit with a Q-value greater than 50.

5. The NXP control-chip-based tire pressure monitoring sensor circuitry of claim 4, wherein, The sensor module employs multi-sensor data fusion processing; the pressure sensor unit uses a MEMS piezoresistive sensor with a measurement range of 0-1500 kPa; the temperature sensor unit uses a semiconductor temperature sensor with a measurement range of -40-125℃; the gravity acceleration sensor unit uses a triaxial MEMS accelerometer; and the control chip integrates a high-precision ADC and digital filtering algorithm.

6. The NXP control-chip-based tire pressure monitoring sensor circuitry of claim 5, wherein, The clock circuit adopts a 26MHz base frequency crystal oscillator design; the crystal Y1 of the 26MHz base frequency crystal oscillator adopts an AT-cut crystal, and the load capacitor is a 12pF NPO ceramic capacitor with an accuracy of ±5%.

7. The NXP control-chip-based tire pressure monitoring sensor circuitry of claim 6, wherein, The tire pressure monitoring sensor circuit system further comprises a dormant low-power control unit connected to the control chip through connection terminal 9. The control chip is built-in with multiple power consumption modes, including a normal working mode, a low-frequency monitoring mode and a deep sleep mode; the system can automatically switch the power consumption mode according to the vehicle motion state detected by the acceleration sensor, the timer timeout or the low-frequency wake-up signal.

8. The NXP control-chip-based tire pressure monitoring sensor circuitry of claim 7, wherein, The radio frequency antenna interface TP2 is connected to the control chip RFOUT pin through a matching network composed of a capacitor C5 and an inductor L3; the LFA pin and the LFB pin connected with the low-frequency antenna interface are connected to the control chip through an LC resonance circuit.

9. The NXP control-chip-based tire pressure monitoring sensor circuitry of claim 8, wherein, The test point is connected to the control chip through connection terminal 1, and can access the key signal nodes in the control chip; the control chip realizes online programming, data reading and function testing through BKGD and RESET pins, and is used for providing a background debugging mode.

10. A tire pressure monitoring sensor circuit device based on NXP control chip, comprising a device body and a monitoring system, characterized in that, The monitoring system is the tire pressure monitoring sensor circuit system of any one of claims 1-9.

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