OCT catheter NFC radio frequency identification circuit board

Abstract

The utility model discloses an OCT (optical coherence tomography) catheter NFC (near field communication) radio frequency identification circuit board which comprises a radio frequency chip unit, a crystal oscillator circuit unit, an EMC (electro magnetic compatibility) filter circuit unit, a matching circuit unit, a receiving circuit unit, a wiring terminal communication unit and an inductance coil unit. The matching circuit unit and the inductance coil unit are integrated on the same circuit board and are connected with the control mainboard through the wiring terminal communication unit; the crystal oscillator circuit unit, the EMC filter circuit unit, the matching circuit unit and the receiving circuit unit are respectively located on a peripheral circuit of the radio frequency chip unit; the inductance coil unit is wound in a circular ring shape to form a radio frequency chip transmitting antenna which is used for transmitting and receiving radio frequency signals of a built-in RFID tag of the OCT catheter. The radio frequency transceiver with the frequency band of 13.56 MHz is integrated on the circuit board, so that the near field communication identification distance is ensured, the RFID tag information built in the OCT catheter is read, and the management efficiency and the safety of equipment are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of OCT catheter identification, in particular to an OCT catheter NFC radio frequency identification circuit board. Background Art

[0002] With the rapid development of medical technology, optical coherence tomography (OCT) catheters are increasingly used in the diagnosis and treatment of cardiovascular diseases. However, during the use of catheters, how to efficiently and accurately identify and manage catheter information has become an urgent problem to be solved. Traditional manual recording and identification methods are not only inefficient, but also prone to errors, increasing medical risks. Therefore, it is particularly important to develop a device that can automatically and quickly identify OCT catheter information. Summary of the invention

[0003] Purpose of the utility model: The technical problem to be solved by the utility model is to provide an OCT catheter NFC radio frequency identification circuit board in view of the shortcomings of the existing technology, aiming to realize non-contact automatic identification and information management of OCT catheters by integrating near-field communication (NFC) technology, so as to improve the efficiency and safety of medical work.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0005] An OCT catheter NFC radio frequency identification circuit board includes a radio frequency chip unit, a crystal oscillator circuit unit, an EMC filter circuit unit, a matching circuit unit, a receiving circuit unit, a terminal communication unit, and an inductor coil unit; the matching circuit unit and the inductor coil unit are integrated on the same circuit board and connected to the control main board through the terminal communication unit; the crystal oscillator circuit unit, the EMC filter circuit unit, the matching circuit unit, and the receiving circuit unit are respectively located on the peripheral circuit of the radio frequency chip unit; the inductor coil unit is wound in a circular ring shape to form a radio frequency chip transmitting antenna for transmitting and receiving radio frequency signals of an RFID tag built into the OCT catheter. The radio frequency transceiver of the 13.56MHz frequency band is integrated into the circuit board to read the information of the RFID tag built into the OCT catheter while ensuring the near field communication identification distance, thereby improving the management efficiency and safety of the equipment.

[0006] Furthermore, the circuit board adopts a double-layer stacked structure, the RF chip unit and its peripheral circuits are placed on the top signal layer, and the inductor coil unit is placed on the bottom signal layer; the RF chip portion of the top signal layer is covered with copper to enhance anti-interference capability and obtain good heat dissipation effect; the bottom signal layer and the inductor coil area are not copper-plated to prevent the copper-plated metal material from affecting the magnetic field generated by the inductor coil when it is working, thereby reducing the performance of the NFC radio frequency identification function.

[0007] Furthermore, the size of the inductance coil unit matches the outer diameter of the OCT catheter, the power supply voltage is fixed, and the recognition distance of NFC is increased by adjusting the matching circuit unit of the chip.

[0008] Furthermore, the RF chip unit uses an NFC chip, model MFRC522, and the RF circuit board is made of RF-4 material.

[0009] Furthermore, the crystal oscillator circuit unit includes a crystal oscillator X1, load capacitors C13 and C14. The crystal oscillator circuit unit is close to the RF chip unit and leaves a distance from the circuit board frame to provide a stable clock signal for the RF chip.

[0010] Furthermore, the EMC filter circuit unit includes power inductors L1 and L2, and capacitors C4 and C7, which together form an LC low-pass filter; among them, power inductor L1 is connected to the TX1 transmission pin of the RF chip, power inductor L2 is connected to the TX2 transmission pin of the RF chip, and power inductors L1 and L2 are spaced apart from each other by a certain distance to avoid mutual inductance effects.

[0011] Furthermore, the matching circuit unit includes load capacitors C3, C8, resonant capacitors C5, C9, C6, C10, and matching resistors R4 and R6; the power of the RF circuit is affected by the internal resistance and external impedance of the chip. When the internal resistance and external impedance of the chip are the same, the transmission power efficiency is the highest. Therefore, the inductance coil resonance frequency is set to 13.56 MHz by adjusting the load capacitors and resonant capacitors; the matching circuit unit is arranged symmetrically to reduce the error between the two transmission signals.

[0012] Furthermore, the receiving circuit unit includes a capacitor C11 for filtering DC signals, and resistors R2 and R3 for forming a voltage dividing circuit, so that the sine wave DC signal at the RX receiving pin of the RF chip is between 1.5 - 3V.

[0013] Furthermore, the terminal communication unit includes a terminal of model SH-8Pin connected to the main board, the working voltage is preferably fixed at 3.3V, and it communicates with the RF chip using the SPI protocol, thereby providing the working mode of the RF chip and its flexible application.

[0014] Furthermore, for the inductance coil unit, the inductance value is between 1 - 1.2 uH, the number of turns is 4, the diameter is between 28 - 32 mm, and the wire spacing is between 48 - 52 mil; preferably, the inductance value is 1.1 uH, the number of turns is 4, the diameter is 30 mm, and the wire spacing is 50 mil.

[0015] Compared with the prior art, the utility model has the following beneficial effects:

[0016] (1) The utility model NFC radio frequency identification circuit integrates a 13.56MHz radio frequency transceiver into a circuit board. While ensuring the near field communication identification distance, it is used to read the RFID tag information built into the OCT catheter, realize non-contact automatic identification and information management of the OCT catheter, and improve the management efficiency and safety of the equipment.

[0017] (2) The utility model uses an NFC radio frequency identification chip to read the information in the RFID tag. It is designed and implemented in a way with minimal cost to solve the recognition distance problem in near field communication. The recognition distance can reach a maximum of 6 cm, meeting the product requirements and also ensuring good performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods, and the above and / or other advantages of the present invention will become more clear.

[0019] Figure 1 This is a schematic diagram of the front layout of the NFC radio frequency identification circuit board of this utility model patent.

[0020] Figure 2 This is a circuit schematic diagram of the NFC radio frequency identification circuit board of the utility model.

[0021] Figure 3 This is a schematic diagram of the copper layout of the radio frequency chip portion of the top signal layer of the radio frequency circuit board of the utility model.

[0022] Figure 4 This is a schematic diagram of the design of the bottom signal layer inductor coil part of the radio frequency circuit board of the utility model.

[0023] Figure 5 This is a schematic diagram of the actual assembly and application of the radio frequency circuit board of the utility model.

[0024] The reference numerals in the figures represent: a radio frequency chip unit 1 , a crystal oscillator circuit unit 2 , an EMC filter circuit unit 3 , a matching circuit unit 4 , a receiving circuit unit 5 , a terminal communication unit 6 , and an inductor coil unit 7 . DETAILED DESCRIPTION

[0025] The present invention can be better understood according to the following embodiments.

[0026] The structures, proportions, sizes, etc. illustrated in the drawings of the specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the utility model, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effect and purpose that can be achieved by the utility model, should still fall within the scope of the technical content disclosed by the utility model. At the same time, the terms such as "upper", "lower", "front", "back", "middle" and so on quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the utility model. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the utility model without substantial change of the technical content.

[0027] like Figure 1 As shown, the utility model OCT catheter NFC radio frequency identification circuit board includes a radio frequency chip unit 1, a crystal oscillator circuit unit 2, an EMC filter circuit unit 3, a matching circuit unit 4, a receiving circuit unit 5, a terminal communication unit 6 and an inductor coil unit 7; the matching circuit unit 4 and the inductor coil unit 7 are integrated on the same circuit board, and connected to the control main board through the terminal communication unit 6; the crystal oscillator circuit unit 2, the EMC filter circuit unit 3, the matching circuit unit 4, and the receiving circuit unit 5 are respectively located on the peripheral circuit of the radio frequency chip unit 1; the inductor coil unit 7 is wound in a circular ring shape, forming a radio frequency chip transmitting antenna, which is used to transmit and receive radio frequency signals of the built-in RFID tag of the OCT catheter. The 13.56MHz frequency band radio frequency transceiver is integrated into the circuit board, which is used to read the built-in RFID tag information of the OCT catheter while ensuring the near field communication identification distance, thereby improving the management efficiency and safety of the equipment.

[0028] Combination Figure 3 and Figure 4 The circuit board adopts a double-layer stacking structure, the RF chip unit 1 and its peripheral circuits are placed on the top signal layer, and the inductor coil unit 7 is placed on the bottom signal layer; the RF chip part of the top signal layer is covered with copper to enhance the anti-interference ability and obtain a good heat dissipation effect; the bottom signal layer and the inductor coil area are not copper-plated to prevent the copper-plated metal material from affecting the magnetic field generated by the inductor coil when it is working, thereby reducing the performance of the NFC radio frequency identification function.

[0029] Combination Figure 2 As shown, the size of the inductor coil unit 7 matches the outer diameter of the OCT catheter, the power supply voltage is fixed, and the NFC recognition distance is increased by adjusting the matching circuit unit 4 of the chip.

[0030] In this embodiment, the RF chip unit 1 uses an NFC chip with the model MFRC522, and the RF circuit board is made of RF-4 material.

[0031] In this embodiment, the crystal oscillator circuit unit 2 includes a 27.12 MHz crystal oscillator X1, 10 pf load capacitors C13 and C14. The crystal oscillator circuit unit 2 is close to the RF chip unit 1 and has a reserved distance from the circuit board border to provide a stable clock signal for the RF chip.

[0032] In this embodiment, the EMC filter circuit unit 3 includes 2.2 uH / 750 mA power inductors L1 and L2, and 56 pf capacitors C4 and C7, which together form an LC low-pass filter. Among them, the power inductor L1 is connected to the TX1 transmission pin of the RF chip, the power inductor L2 is connected to the TX2 transmission pin of the RF chip, and the power inductors L1 and L2 are spaced a certain distance from each other to avoid mutual inductance effects.

[0033] In this embodiment, the matching circuit unit 4 includes 16 pf load capacitors C3 and C8, 220 pf resonant capacitors C5 and C9, 43 pf resonant capacitors C6 and C10, and 1.5 Ω matching resistors R4 and R6. The power of the RF circuit is affected by the internal resistance of the chip and the external impedance. When the internal resistance of the chip and the external impedance are the same, the transmission power efficiency is the highest. Therefore, by adjusting the load capacitors and resonant capacitors, the resonant frequency of the inductor coil is set to 13.56 MHz. The matching circuit unit 4 is symmetrically distributed to reduce the error between the two transmission signals.

[0034] In this embodiment, the receiving circuit unit 5 includes a 1 nf capacitor C11 for filtering DC signals, and 820 Ω resistor R2 and 2.7 K resistor R3 for forming a voltage dividing circuit, so that the sine wave DC signal at the RX receiving pin of the RF chip is between 1.5 - 3V.

[0035] In this embodiment, the terminal communication unit 6 includes a terminal with the model SH-8Pin connected to the main board. The working voltage is preferably fixed at 3.3V, and it communicates with the RF chip using the SPI protocol, thereby providing the working mode of the RF chip and its flexible applications.

[0036] In this embodiment, the inductance value of the inductor coil unit 7 is 1.1 uH, the number of turns is 4, the diameter is 30 mm, and the wire spacing is 50 mil.

[0037] Combined with Figure 5During use, the NFC radio frequency identification circuit board is installed and fixed on the catheter seat, and an electrical connection wire is used to connect the NFC circuit board interface to the main control circuit of the motion controller to achieve communication and control between the main control and the NFC circuit. When working normally, screw the catheter (the catheter with the NFC identification tag) onto the catheter seat. While screwing on the catheter, trigger the NFC identification function. At this time, the NFC circuit board emits a radio frequency magnetic field with a frequency of 13.56 MHz through the induction coil on the circuit board. The NFC passive tag at the catheter end converts the magnetic field energy into an electrical signal to activate the tag, realizing communication between the NFC device end and the catheter end. Furthermore, the information written before leaving the factory at the catheter end is sent back to the NFC circuit board for decryption and analysis, and the information of the catheter is read. Finally, the rotary motor on the device passes through the grooved area (inductor coil unit 7) of the NFC circuit board to dock with the catheter, and then the catheter is rotated and pulled back to complete a retraction process.

[0038] The present utility model provides an idea and method for an OCT catheter NFC radio frequency identification circuit board. There are many methods and ways to specifically implement this technical solution. The above description is only the preferred embodiment of the present utility model. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present utility model, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present utility model. Each component not clearly defined in this embodiment can be realized by using existing technologies.

Claims

1. An OCT catheter NFC radio frequency identification circuit board, characterized in that, The invention comprises a radio frequency chip unit (1), a crystal oscillator circuit unit (2), an EMC filter circuit unit (3), a matching circuit unit (4), a receiving circuit unit (5), a terminal communication unit (6) and an inductor coil unit (7); the matching circuit unit (4) and the inductor coil unit (7) are integrated on the same circuit board and connected to a control main board via the terminal communication unit (6); the crystal oscillator circuit unit (2), the EMC filter circuit unit (3), the matching circuit unit (4) and the receiving circuit unit (5) are respectively located on the peripheral circuit of the radio frequency chip unit (1); the inductor coil unit (7) is wound in a circular ring shape to form a radio frequency chip transmitting antenna for transmitting and receiving radio frequency signals of an RFID tag built into an OCT catheter; The circuit board adopts a double-layer stacked structure, the radio frequency chip unit (1) and its peripheral circuits are placed on the top signal layer, and the inductor coil unit (7) is placed on the bottom signal layer; the radio frequency chip portion of the top signal layer is covered with copper for heat dissipation; the bottom signal layer and the inductor coil area are not covered with copper; The matching circuit unit (4) comprises a load capacitor C3, a load capacitor C8, a resonant capacitor C5, a resonant capacitor C9, a resonant capacitor C6, a resonant capacitor C10, and a matching resistor R4 and a matching resistor R6. The resonant frequency of the inductor coil is adjusted to 13.56 MHz. The matching circuit unit (4) is symmetrically distributed to reduce the error of the two transmission signals.

2. The OCT catheter NFC radio frequency identification circuit board according to claim 1, characterized in that The size of the inductor coil unit (7) matches the outer diameter of the OCT catheter, the power supply voltage is fixed, and the NFC recognition distance is increased by adjusting the matching circuit unit (4) of the chip.

3. The OCT catheter NFC radio frequency identification circuit board according to claim 1, wherein The radio frequency chip unit (1) adopts an NFC chip, model MFRC522.

4. The OCT catheter NFC radio frequency identification circuit board according to claim 1, characterized in that, The crystal oscillator circuit unit (2) comprises a crystal oscillator X1, a load capacitor C13, and a load capacitor C14. The crystal oscillator circuit unit (2) and the radio frequency chip unit (1) are close to each other and have a reserved distance from the frame of the circuit board, so as to provide a stable clock signal for the radio frequency chip.

5. The OCT catheter NFC radio frequency identification circuit board according to claim 1, characterized in that, The EMC filter circuit unit (3) comprises a power inductor L1, a power inductor L2, and a capacitor C4 and a capacitor C7, which together form an LC low-pass filter; wherein the power inductor L1 is connected to the TX1 transmitting pin of the radio frequency chip, the power inductor L2 is connected to the TX2 transmitting pin of the radio frequency chip, and the power inductor L1 and the power inductor L2 are spaced a certain distance from each other to avoid output mutual inductance effect.

6. The OCT catheter NFC radio frequency identification circuit board according to claim 1, characterized in that, The receiving circuit unit (5) comprises a capacitor C11 for filtering out DC signals, and resistors R2 and R3 for forming a voltage divider circuit, so that the sinusoidal DC signal at the RX receiving pin of the radio frequency chip is between 1.5V and 3V.

7. The OCT catheter NFC radio frequency identification circuit board according to claim 1, characterized in that The wiring terminal communication unit (6) comprises a terminal of model SH-8Pin connected to the mainboard, and is connected to the radio frequency chip by using the SPI protocol for communication.

8. The OCT catheter NFC radio frequency identification circuit board according to claim 2, characterized in that, The inductance value of the inductor coil unit (7) is between 1-1.2uH, the number of turns is 4, the diameter is between 28-32mm, and the wiring spacing is between 48-52mil.

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