Electrical arrangement of sensor accessories in electromagnetic navigation systems

Abstract

An electrical arrangement of a sensor accessory in an electromagnetic navigation system is disclosed. The sensor accessory comprises a multi-layer circuit, a first magnetic field sensor and a second magnetic field sensor. The multilayer circuit extends along a longitudinal axis between a proximal end and a distal end. The multilayer circuit includes a plurality of electrical pads positioned at the proximal end. The first magnetic field sensor is coupled to the multilayer circuit and has a primary sensing direction aligned with the longitudinal axis. The second magnetic field sensor is coupled to the multilayer circuit and is oriented relative to the first magnetic field sensor such that the second magnetic field sensor has a primary sensing direction aligned with an axis orthogonal to the longitudinal axis.

Description

[0001] This application is a divisional application of the patent application with application number "201980012611.9", application date "January 15, 2019", and titled "Electrical layout of sensor accessories in electromagnetic navigation system".

[0002] Related Applications

[0003] This application claims priority to provisional application No. 62 / 617,925 filed on January 16, 2018, the entire contents of which are incorporated herein by reference. Technical Field

[0004] The present disclosure relates to systems, methods and devices for tracking items. More specifically, the present disclosure relates to systems, methods and devices for electromagnetically tracking medical devices used in medical procedures. Background Art

[0005] Various systems, methods, and devices may be used to track medical devices. A tracking system may use a generated magnetic field sensed by at least one tracking sensor in a tracked medical device. The generated magnetic field provides a fixed frame of reference, and the tracking sensor senses the magnetic field to determine the position and orientation of the sensor relative to the fixed frame of reference. Summary of the invention

[0006] In Example 1, a sensor assembly includes a multilayer circuit, a first magnetic field sensor, and a second magnetic field sensor. The multilayer circuit extends between a proximal end and a distal end along a longitudinal axis. The multilayer circuit includes a plurality of electrical pads positioned at the proximal end. The first magnetic field sensor is coupled to the multilayer circuit and has a primary sensing direction aligned with the longitudinal axis. The second magnetic field sensor is coupled to the multilayer circuit and oriented relative to the first magnetic field sensor so that the second magnetic field sensor has a primary sensing direction aligned with an axis orthogonal to the longitudinal axis.

[0007] In Example 2, the sensor accessory of Example 1, wherein the multilayer circuit includes a flexible substrate layer, wherein a first subset of the plurality of electrical pads is positioned on a first side of the flexible substrate layer, and wherein a second subset of the plurality of electrical pads is positioned on a second side of the flexible substrate layer opposite the first side.

[0008] In Example 3, the sensor assembly of any of Examples 1-2, wherein the proximal region of the multilayer circuit is folded such that at least one of the plurality of electrical pads is positioned on a different plane than the other plurality of electrical pads.

[0009] In Example 4, the sensor assembly of any of Examples 1-3, wherein the proximal region of the multilayer circuit is generally c-shaped.

[0010] In Example 5, the sensor assembly of any of Examples 3-4, wherein the proximal region includes a folded portion that is only partially covered by the mask layer, such that a portion of the flexible substrate layer is exposed.

[0011] In Example 6, the sensor assembly of any of Examples 1-5, wherein the multilayer circuit includes six to nine electrical pads at the proximal end.

[0012] In Example 7, the sensor assembly of any of Examples 1-6 further includes a plurality of electrical leads, each electrical lead electrically coupled to one of the plurality of electrical pads.

[0013] In Example 8, the sensor assembly of any of Examples 1-7 further includes a housing surrounding the multilayer circuit, the first magnetic sensor, and the second magnetic sensor.

[0014] In the sensor assembly of Example 9, the sensor assembly of Example 8, wherein the housing includes four quadrants of substantially equal size, wherein at least one electrical lead is positioned within each of the four quadrants.

[0015] In Example 10, the sensor accessory of any of Examples 8-9, wherein the shell is cylindrical, polygonal or rectangular.

[0016] In Example 11, the sensor assembly of any of Examples 8-10, wherein the cross-sectional area of ​​the housing is .096-.79 mm 2 .

[0017] In Example 12, the sensor assembly of any of Examples 8-11, wherein the housing comprises epoxy.

[0018] In Example 13, the sensor accessory of any of Examples 8-12, wherein the housing includes a shell.

[0019] In Example 14, the sensor assembly of any of Examples 1-13, wherein the first magnetic field sensor and the second magnetic field sensor include one of an inductive sensing coil, a magnetoresistive sensing element, a giant magnetoresistive sensing element, and a fluxgate sensing element.

[0020] In Example 15, the sensor assembly of any of Examples 1-14, wherein the first magnetic field sensor or the second magnetic field sensor is a multi-axis sensor and includes a second main sensing direction.

[0021] In Example 16, the system includes a sensor accessory having a multilayer circuit, a first magnetic field sensor, and a second magnetic field sensor. The multilayer circuit includes a proximal section, a distal section, and a longitudinal axis. The proximal section includes a plurality of electrical pads and is at least partially folded. The first magnetic field sensor is coupled to the multilayer circuit at the distal section and has a primary sensing direction aligned with the longitudinal axis. The second magnetic field sensor is coupled to the multilayer circuit at the distal section and is oriented relative to the first magnetic field sensor so that the second magnetic field sensor has a primary sensing direction aligned with an axis orthogonal to the longitudinal axis.

[0022] In Example 17, the system of Example 16, wherein the multilayer circuit includes a flexible substrate layer, wherein a first subset of the plurality of electrical pads is positioned on a first side of the flexible substrate layer, and wherein a second subset of the plurality of electrical pads is positioned on a second side of the flexible substrate layer opposite the first side.

[0023] In Example 18, the system of Example 16, the proximal region of the multi-layer circuit is substantially c-shaped.

[0024] In Example 19, the system of Example 16, wherein the proximal region of the multilayer circuit includes a flexible substrate only partially covered by the mask layer such that a portion of the flexible substrate layer is exposed.

[0025] In Example 20, the system of Example 16, wherein the multilayer circuit includes six to nine electrical pads at the proximal region.

[0026] In Example 21, the system of Example 20 further includes a plurality of electrical leads, each electrical lead electrically coupled to one of the plurality of electrical pads.

[0027] In Example 22, the system of Example 16 further includes a housing surrounding the multi-layer circuit, the first magnetic sensor, and the second magnetic sensor.

[0028] In Example 23, the system of Example 22, wherein the housing includes four quadrants of substantially equal size, wherein at least one electrical lead is located within each of the four quadrants.

[0029] In Example 24, the system of Example 22, wherein the shell is cylindrical, polygonal, or rectangular.

[0030] In Example 25, the system of Example 22, wherein the cross-sectional area of ​​the housing is .096-.79 mm 2 .

[0031] In Example 26, the system of Example 22, wherein the housing comprises epoxy.

[0032] In Example 27, the system of Example 22, wherein the housing comprises an outer shell and is at least partially filled with epoxy.

[0033] In Example 28, the system of Example 16 further includes a third magnetic field sensor coupled to the multilayer circuit at the distal portion and oriented relative to the first magnetic field sensor such that the third magnetic field sensor has a primary sensing direction orthogonal to the longitudinal axis.

[0034] In Example 29, the system of Example 16, wherein the proximal region includes a first leg, a second leg, and a bend positioned between the first leg and the second leg.

[0035] In Example 30, the system of Example 29, wherein a first subset of the plurality of electrical pads is positioned on the first leg, and wherein a second subset of the plurality of electrical pads is positioned on the second leg.

[0036] In Example 31, the system of Example 16, wherein the first magnetic field sensor or the second magnetic field sensor is a multi-axis sensor and includes a second primary sensing direction.

[0037] In Example 32, the system of any of Examples 16-31 further includes a medical device, wherein the sensor assembly is positioned within the medical device.

[0038] In Example 33, a method for forming a multilayer circuit is disclosed, the multilayer circuit having a proximal portion, a distal portion, a first set of a plurality of electrical pads positioned at the proximal portion, and a second set of a plurality of electrical pads positioned at the distal portion. The method includes electrically coupling a plurality of magnetic field sensors to the second set of the plurality of electrical pads, electrically coupling a plurality of electrical leads each to one of the first set of the plurality of electrical pads, the electrical pads being positioned in substantially the same plane, and folding the proximal portion so that the proximal portion includes a bend having a substantially constant bend radius so that the first set of the plurality of electrical pads are no longer positioned in substantially the same plane.

[0039] In Example 34, the method of Example 33 further includes: after the folding step, positioning the multi-layer circuit in the housing.

[0040] In Example 35, the method of any of Examples 33-34 further includes: after the folding step, encapsulating at least a portion of the multilayer circuit in an epoxy resin.

[0041] In Example 36, a medical device includes the sensor assembly of any of Examples 1-15.

[0042] In Example 37, the medical device of Example 36, wherein the medical device is a catheter.

[0043] In Example 38, the medical device of Example 37, wherein the sensor assembly is positioned within the catheter.

[0044] In Example 39, the medical device of Example 37, wherein the sensor assembly is positioned at or near the distal end of the catheter.

[0045] While multiple embodiments are disclosed, other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the present invention.Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A schematic diagram of a tracking system according to certain embodiments of the present disclosure is shown.

[0047] Figure 2 Shown are block representations of computing devices in accordance with certain embodiments of the present disclosure.

[0048] Figure 3 A side view of a sensor assembly according to certain embodiments of the present disclosure is shown.

[0049] Figure 4 Shows Figure 3 Cross-sectional side view of the sensor assembly.

[0050] Figure 5 Shows Figure 3 A cross-sectional perspective view of a sensor assembly.

[0051] Figure 6 Shows Figure 3 A top view of a multi-layer circuit assembly.

[0052] Figure 7 A cross-sectional perspective view of a sensor assembly according to certain embodiments of the present disclosure is shown.

[0053] Figure 8 Shows Figure 7 Cross-sectional side view of the sensor assembly.

[0054] Fig. 9 A cross-sectional perspective view of a sensor assembly according to certain embodiments of the present disclosure is shown.

[0055] Fig.10 Shows Fig. 9 Cross-sectional side view of the sensor assembly.

[0056] Fig.11 A top view of a multi-layer circuit assembly according to certain embodiments of the present disclosure is shown.

[0057] Fig.12 Some embodiments of the present disclosure include Fig.11 A cross-sectional side view of a sensor assembly of a multi-layer sensor assembly.

[0058] Although the present invention is susceptible to various modifications and alternative forms, specific embodiments are shown by way of example in the accompanying drawings and are described in detail below. However, it is not intended to limit the present invention to the specific embodiments described. On the contrary, the present invention is intended to cover all modifications, equivalents and substitutes falling within the scope of the invention defined by the appended claims. DETAILED DESCRIPTION

[0059] During a medical procedure, a medical device such as a probe (e.g., catheter, guidewire, endoscope) is inserted into a patient. To track the position and orientation of the probe within the patient, the probe can be equipped with a magnetic field sensor that detects various magnetic fields generated by a transmitter near the patient.

[0060] Figure 1 1 is a schematic block diagram depicting a tracking system 100 configured to determine location information corresponding to a medical device 104 based on information collected using a receiver (e.g., a sensor) 102 associated with the medical device 104. The information collected by the receiver 102 includes received field signals corresponding to an electromagnetic field defined by a set of electromagnetic signals transmitted by one or more magnetic field transmitter accessories 106, 108, and 110. According to an embodiment, the one or more magnetic field transmitter accessories 106, 108, and 110 are configured to transmit (e.g., radiate) electromagnetic signals that generate a magnetic field in which a subject 112 is disposed. According to an embodiment, the system 100 includes a magnetic field controller 114 that is configured to manage the operation of the magnetic field transmitter accessories 106, 108, and 110.

[0061] The receiver 102 (e.g., magnetic field sensor) (which may include one or more receivers / sensors) may be configured to generate an electrical response to one or more magnetic fields generated by the magnetic field transmitter assemblies 106, 108, and 110. For example, the receiver 102 may include one or more magnetic field sensors (such as inductive sensing coils) and / or various sensing elements, such as magnetoresistive (MR) sensing elements (e.g., anisotropic magnetoresistive (AMR) sensing elements, giant magnetoresistive (GMR) sensing elements, tunneling magnetoresistive (TMR) sensing elements, Hall effect sensing elements, giant magnetoresistive (CMR) sensing elements, special magnetoresistive (EMR) sensing elements, spin Hall sensing elements, and the like), giant magneto-impedance (GMI) sensing elements, and / or fluxgate sensing elements. The receiver 102 is configured to sense the generated magnetic field and provide a tracking signal indicating the position and orientation of the receiver 102 in up to six degrees of freedom (i.e., x, y, and z measurements, as well as pitch, yaw, and roll angles). Typically, the number of degrees of freedom that a tracking system is able to track depends on the number of magnetic field sensors and magnetic field generators. For example, a tracking system with a single magnetic field sensor may not be able to track roll angle, and is therefore limited to tracking with only five degrees of freedom (i.e., x, y, and z coordinates, as well as pitch and yaw angles). This is because the magnetic field sensed by a single magnetic field sensor does not change due to the "rolling" of the single magnetic field sensor. The magnetic field sensor can be powered by a voltage or current to drive or excite the elements of the magnetic field sensor. The magnetic field sensor element receives a voltage or current, and in response to one or more of the generated magnetic fields, the magnetic field sensor element generates a sensing signal that is sent to the magnetic field controller 114.

[0062] like Figure 1 As shown in FIG. 1 , the magnetic field controller 114 includes a signal generator 116 configured to provide a drive current to each of the magnetic field transmitter accessories 106, 108, and 110, thereby causing each magnetic field transmitter accessory to transmit an electromagnetic signal. In some embodiments, the signal generator 116 is configured to provide a variable (e.g., sinusoidal) drive current to the magnetic field transmitter accessories 106, 108, and 110. The magnetic field controller 114 may be implemented using firmware, integrated circuits, and / or software modules that interact or are combined with each other. For example, the magnetic field controller 114 may include a processor (see FIG. 1 ). Figure 2 ) to execute computer readable instructions / code. Such instructions may be stored on a non-transitory computer readable medium (see Figure 2 ) and transmitted to the processor for execution. In some embodiments, the magnetic field controller 114 can be implemented in one or more application specific integrated circuits and / or other forms of circuits suitable for controlling and processing magnetic tracking signals and information.

[0063] The sensed magnetic field signal may include multiple magnetic field signals, each of which may be processed to extract field components corresponding to one or more magnetic field transmitter accessories. The sensed magnetic field signal is transmitted to a signal processor 118, which is configured to analyze the sensed magnetic field signal to determine position information corresponding to the receiver 102 (and therefore the medical device 104). The position information may include any type of information associated with the position and / or positioning of the medical device 104, such as, for example, position, relative position (e.g., position relative to another device and / or position), location, orientation, speed, acceleration, and / or the like. As mentioned above, tracking based on a rotating magnetic field can utilize the phase (e.g., phase difference) of the sensed magnetic field signal to determine the position and orientation of the probe.

[0064] The tracking system 100 may also include at least one sensor configured and arranged to sense the magnetic field generated by the magnetic field transmitter accessories 106-110. The sensor may be a magnetic sensor (e.g., a two-axis magnetic sensor, a three-axis magnetic sensor) and may be positioned at a known reference point near the magnetic field transmitter accessories 106-110 to act as a reference sensor. For example, one or more sensors may be coupled to the subject's bed, the subject himself, the arm of an X-ray machine, or other points at a known distance from the magnetic field transmitter accessories 106-110. In some embodiments, at least one sensor is mounted on one of the magnetic field transmitter accessories 106-110.

[0065] The medical device 104 may include, for example, a catheter (e.g., a mapping catheter, an ablation catheter, a diagnostic catheter, an introducer), an endoscopic probe or cannula, an implantable medical device (e.g., a control device, a monitoring device, a pacemaker, an implantable cardioverter-defibrillator (ICD), a cardiac resynchronization therapy (CRT) device, CRT-D), a guidewire, an endoscope, a biopsy needle, an ultrasound device, a reference patch, a robot, and / or the like. For example, in an embodiment, the medical device 104 may include a mapping catheter associated with an anatomical mapping system. The medical device 104 may include any other type of device configured to be at least temporarily arranged within the subject 112. The subject 112 may be a human, a dog, a pig, and / or any other animal having physiological parameters that can be recorded. For example, in an embodiment, the subject 112 may be a human patient.

[0066] like Figure 1As shown in , the medical device 104 can be configured to be arranged in the body of the subject 112, and can be configured to be communicatively coupled to the signal processor 118 via a communication link 120 (shown in dashed lines). In an embodiment, the communication link 120 can be or include a wired communication link (e.g., serial communication), a wireless communication link (such as, for example, a short-range radio link such as Bluetooth, IEEE 802.11, a proprietary wireless protocol, and / or the like). The term "communication link" can refer to the ability to transmit a certain type of information in at least one direction between at least two devices, and should not be understood as being limited to a direct, persistent, or otherwise limited communication channel. That is, in some embodiments, the communication link 120 can be a persistent communication link, an intermittent communication link, an ad-hoc communication link, and / or the like. The communication link 120 may refer to direct communication between the medical device 104 and the signal processor 118, and / or indirect communication that propagates between the medical device 104 and the signal processor 118 via at least one other device (e.g., a repeater, a router, a hub, and / or the like). The communication link 120 may facilitate unidirectional and / or bidirectional communication between the medical device 104 and the signal processor 118. Data and / or control signals may be sent between the medical device 104 and the signal processor 118 to coordinate the functions of the medical device 104 and / or the signal processor 118.

[0067] Signal processor 118 also includes a positioning unit 122, which is configured to determine position information corresponding to medical device 104 based on the sensed field signal (e.g., the phase, amplitude, phase difference, and / or amplitude difference of the sensed field signal). Positioning unit 122 can be configured to determine position information based on any position determination technology using magnetic navigation. According to various embodiments of the disclosed subject matter, Figure 1 Any number of components depicted in (e.g., field controller 114, signal generator 116, signal processor 118) may be implemented as a single unit or a combination of multiple devices on one or more computing devices. System 100 may include a display for visualizing the position and / or orientation of medical device 104 in subject 112.

[0068] Figure 2 1 is a schematic block diagram depicting an illustrative computing device 200 according to an embodiment of the present disclosure. Computing device 200 may include any type of computing device suitable for implementing aspects of embodiments of the disclosed subject matter. Examples of computing devices include special-purpose computing devices or general-purpose computing devices, such as "workstations," "servers," "laptops," "desktops," "tablet computers," "handheld devices," "general-purpose graphics processing units (GPGPUs)," and the like, all of which are referenced to the various components of tracking system 100 and / or computing device 200 in the examples. Figure 1 and Figure 2 within the scope of the envisioned.

[0069] In an embodiment, computing device 200 includes bus 210 that directly and / or indirectly couples the following devices: processor 220, memory 230, input / output (I / O) ports 240, I / O components 250, and power supply 260. Any number of additional components, different components, and / or combinations of components may also be included in computing device 200. I / O components 250 may include presentation components (such as, for example, a display device, a speaker, a printing device, and / or the like) and / or input components (such as, for example, a microphone, a joystick, a satellite dish, a scanner, a printer, a wireless device, a keyboard, a pen, a voice input device, a touch input device, a touch screen device, an interactive display device, a mouse, and / or the like) configured to present information to a user.

[0070] Bus 210 represents one or more buses (such as, for example, an address bus, a data bus, or a combination thereof). Similarly, in an embodiment, computing device 200 may include multiple processors 220, multiple memory components 230, multiple I / O ports 240, multiple I / O components 250, and / or multiple power supplies 260. In addition, any number of these components or combinations thereof may be distributed and / or replicated across multiple computing devices. By way of example only, processor 220 may include signal processor 118, but other suitable configurations are also contemplated to suit different applications.

[0071] In an embodiment, memory 230 includes computer-readable media in the form of volatile memory and / or non-volatile memory, and may be removable, non-removable, or a combination thereof. Examples of media include random access memory (RAM); read-only memory (ROM); electrically erasable programmable read-only memory (EEPROM); flash memory; optical or holographic media; cassettes, tapes, disk storage, or other magnetic storage devices; data transmission; and / or any other media that can be used to store information and can be accessed by a computing device, such as, for example, quantum state memory and / or the like. In an embodiment, memory 230 stores computer-executable instructions 290 for causing processor 220 to implement aspects of embodiments of system components discussed herein and / or to perform aspects of embodiments of methods and programs discussed herein.

[0072] Computer executable instructions 290 may include, for example, computer code, machine usable instructions, and the like, such as, for example, program components that are executable by one or more processors 220 associated with computing device 200. Program components may be programmed using any number of different programming environments, including various languages, development toolkits, frameworks, and / or the like. Some or all of the functionality contemplated herein may also or alternatively be implemented in hardware and / or firmware.

[0073] Figure 2 The illustrative computing device 200 shown in the is not intended to suggest any limitation as to the scope of use or functionality of the embodiments of the present disclosure. Nor should the illustrative computing device 200 be interpreted as having any dependency or requirement relating to any single component or combination of components shown therein. Additionally, in the embodiments, Figure 2 Various components depicted in the drawings may be integrated with various of the other components depicted therein (and / or components not shown), all of which are considered to be within the scope of the present disclosure.

[0074] Figure 3-Figure 5 shows that it can be used in medical devices (such as Figure 1 The sensor assembly 300 is used in a medical device 104 in a medical device. For example, the sensor assembly 300 can be positioned within the medical device (e.g., at or near a distal end of the medical device). The sensor assembly 300 includes a multi-layer circuit assembly 302 electrically coupled to electrical leads 304 and positioned within a housing 306. Figure 6 Multi-layer circuit assembly 302 is shown before multi-layer circuit 308 is formed into its final shape and before multi-layer circuit assembly 302 is incorporated into sensor assembly 300 .

[0075] The multilayer circuit assembly 302 includes a multilayer circuit 308 extending between a proximal end 310A and a distal end 310B. The multilayer circuit 308 includes a flexible substrate 312 (e.g., polyimide, polyester / PET, PEEK, parylene, LCP, PEN, PEI, FEP), a first mask layer 314A, a second mask layer 314B, an electrical lead pad 316 (see FIG. Figure 4-Figure 6 ), electrical installation gasket 318 (see Figure 5-Figure 6 ) and electrical traces (not shown) that electrically couple certain electrical lead pads 316 to certain electrical mounting pads 318. First mask layer 314A and second mask layer 314B are positioned on opposite sides of flexible substrate 312. In certain embodiments, multilayer circuit 308 has a thickness of 5-100 microns.

[0076] The multilayer circuit assembly 302 also includes a first magnetic field sensor 320A, a second magnetic field sensor 320B, and a third magnetic field sensor 320C, and a first sensor circuit 322A, a second sensor circuit 322B, and a third sensor circuit 322C (e.g., an application specific integrated circuit (ASIC), a circuit having one or more diodes and one or more capacitors). Figure 3-Figure 6 As shown in , magnetic field sensors 320A-320C and sensor circuits 322A-322C can be implemented on separate dies and positioned adjacent to each other. In such embodiments, magnetic field sensors 320A-320C and sensor circuits 322A-322C can be electrically and communicatively coupled together. In certain embodiments, corresponding magnetic field sensors 320A-320C and sensor circuits 322A-322C can be implemented on the same die or substrate (e.g., a monolithic design). For example, magnetic field sensors 320A-320C can be manufactured on top of corresponding sensor circuits 322A-322C.

[0077] The magnetic field sensors 320A, 320B, and 320C may include sensors (such as inductive sensing coils) and / or various sensing elements, such as MR sensing elements (e.g., AMR sensing elements, GMR sensing elements, TMR sensing elements, Hall effect sensing elements, CMR sensing elements, EMR sensing elements, spin Hall sensing elements, and the like), GMI sensing elements, and / or fluxgate sensing elements. The MR sensing elements are configured to sense magnetic fields, such as Figure 1 The multilayer circuit assembly 302 may also feature other types of sensors, such as temperature sensors, ultrasonic sensors, etc. The sensor signals generated by the magnetic field sensors 320A-320C may be transmitted from the sensor assembly 300 to a controller wirelessly or via one or more conductors, such as Figure 1 A magnetic field controller 114 is provided.

[0078] In some embodiments, the magnetic field sensors 320A-320C are arranged in a two-axis, six-degree-of-freedom arrangement. In such an embodiment, the first magnetic field sensor 320A and the second magnetic field sensor 320B are oriented so that their primary sensing directions are aligned along the longitudinal axis 324 (e.g., the X-axis) of the sensor accessory 300. The third magnetic field sensor 320C is oriented so that its primary sensing direction is aligned along an axis (e.g., the Y-axis) that is orthogonal to the longitudinal axis 324. In some embodiments, the magnetic field sensors 320A-320C are arranged in a three-axis, six-degree-of-freedom arrangement. In such an embodiment, the primary sensing directions of the magnetic field sensors are orthogonal to each other. Although the first magnetic field sensor 320A, the second magnetic field sensor 320B, and the third magnetic field sensor 320C and the first sensor circuit 322A, the second sensor circuit 322B, and the third sensor circuit 322C are shown as being oriented substantially in the same plane, the magnetic field sensors may be oriented in different planes (e.g., orthogonal planes). Although Figure 3-Figure 6 The magnetic field sensors 320A-320C and the sensor circuits 322A-322C are shown positioned on the same side of the multilayer circuit 308, but the magnetic field sensors 320A-320C and the sensor circuits 322A-322C can be distributed between the two sides of the multilayer circuit 308. Example orientations of magnetic field sensors on sensor assemblies are disclosed in U.S. Patent Application No. 62 / 455,339, entitled "SENSOR ASSEMBLIES FOR ELECTROMAGNETIC NAVIGATION SYSTEMS", which is incorporated herein by reference for the purpose of disclosing the orientation of magnetic field sensors on sensor assemblies. In some embodiments, the multilayer circuit assembly 302 includes only two magnetic field sensors with different main sensing directions. In some embodiments, one or more of the magnetic field sensors are dual-axis or tri-axis sensors having two or three main sensing directions, respectively. The first, second, and third magnetic field sensors 320A-320C are configured to generate response sensing signals in response to a magnetic field. The sensing signals are used to determine the position and orientation of the sensor assembly 300.

[0079] In some embodiments, the magnetic field sensors 320A-320C and / or the sensor circuits 322A-322C are electrically coupled to the corresponding electrical mounting pads 318 via wire bonds 326. In some embodiments, the magnetic field sensors 320A-320C and / or the sensor circuits 322A-322C are electrically coupled to the corresponding electrical mounting pads 318 via flip-chip, through-silicon vias, fan-out wafer-level packaging, or other packaging formats known in the art. As previously mentioned, the electrical mounting pads 318 are electrically coupled to the electrical lead pads 316 via electrical traces. Example electrical connections among magnetic field sensors, sensor circuits, electrical lead pads, and electrical mounting pads are disclosed in U.S. Patent Application No. 62 / 455,299, entitled “ELECTROMAGNETIC NAVIGATION SYSTEM WITH MAGNETO-RESISTIVESENSORS AND APPLICATION-SPECIFIC INTEGRATED CIRCUITS,” which is incorporated herein by reference for the purpose of disclosing example electrical connections.

[0080] In some embodiments, when magnetic field sensors 320A-320C are arranged in a dual-axis or tri-axis arrangement, multi-layer circuit 308 includes six or seven electrical lead pads 316, and multi-layer circuit assembly 302 includes six or seven electrical leads 304. In a dual-axis arrangement, multi-layer circuit assembly 302 may include six electrical lead pads 316: one ground lead pad, one bias lead pad, one positive X-axis signal lead pad, one negative X-axis signal lead pad, one positive Y-axis signal lead pad, and one negative Y-axis signal lead pad. In a tri-axis arrangement, multi-layer circuit assembly 302 may include eight or nine electrical lead pads: one ground lead pad, one bias lead pad, one positive X-axis signal lead pad, one negative X-axis signal lead pad, one positive Y-axis signal lead pad, one negative Y-axis signal lead pad, one positive Z-axis signal lead pad, one negative Z-axis signal lead pad, and a reset lead pad. In some embodiments, electrical leads 304 include a conductive material (eg, copper), and electrical lead pads 316 are spaced apart from one another at proximal end 310A for adequate electrical isolation. In some embodiments, the magnetic field sensors are arranged in a single-axis, five-degree-of-freedom arrangement.

[0081] Figure 6Multilayer circuit assembly 302 is shown before multilayer circuit 308 is formed into its final shape and before multilayer circuit assembly 302 is incorporated into sensor assembly 300. For each of electrical lead pads 316 and electrical mounting pads 318, first mask layer 314A is removed so that the pad is exposed and accessible for electrical coupling to corresponding electrical leads 304 and wire bonds 326, etc.

[0082] The multilayer circuit 308 includes a proximal section 328 having exposed electrical lead pads 316 and a distal section 330 having exposed electrical mounting pads 318. During manufacturing, the electrical leads 304 may be coupled to the electrical lead pads 316 via a variety of methods (e.g., reflow solder (so that the solder melts and solidifies), soldering (laser and the like), tape automated bonding, thermal compression, ultrasonic compression, anisotropic conductive film, soldering, and the like) to mechanically and electrically couple the electrical leads 304 and the electrical lead pads 316. Providing the electrical lead pads 316 on one side of the multilayer circuit 308 makes manufacturing easier, for example, because the solder can be reflowed once on only one side of the multilayer circuit 308. As mentioned above, the magnetic field sensors 320A-320C and the sensor circuits 322A-322C may be electrically coupled to the electrical mounting pads 318 via wire bonding, flip chip, through silicon vias, fan-out wafer level packaging, and the like. After the various electrical couplings are made, the proximal section 328 may be folded (eg, curled).

[0083] like Figure 3-Figure 5 , the proximal section 328 is folded so that the multi-layer circuit 308 (and therefore the multi-layer circuit assembly 302) consumes less cross-sectional area at the proximal end 310A of the multi-layer circuit assembly 302. In some embodiments, the proximal section 328 is folded and formed into a generally c-shape. In such embodiments, the proximal section 328 has a substantially constant bend radius throughout the length of the cross section. Figure 4 As shown in FIG. 1 , in some embodiments, the proximal section 328 includes a first leg 330A and a second leg 330B and a bend 332 extending between the first leg 330A and the second leg 330B. The electrical lead pad 316 is positioned on the first leg 330A and the second leg 330B. The bend 332 has a substantially constant bend radius throughout its cross-sectional length, while the first leg 330A and the second leg 330B are substantially straight. Figure 4 , once the multi-layer circuit 308 is folded, the electrical leads 304 and the electrical lead pads 316 are positioned within the interior region of the proximal section 328. In other embodiments, once the multi-layer circuit 308 is folded, the electrical leads 304 and the electrical lead pads 316 can be positioned outside the interior region of the proximal section 328 closer to the housing 306.

[0084] like Figure 3 and Figure 6 , the proximal section 328 has a length L extending along the longitudinal axis 324. Only a portion of the proximal section 328 is covered by the second mask layer 314B, so that the flexible substrate 312 is exposed. Limiting the coverage of the second mask layer 314B on the proximal section 328 can provide additional flexibility for folding or curling the proximal section 328. For example, without complete coverage of the second mask layer 314B, the proximal section 328 can be folded with a small bending radius. In some embodiments, in order to provide additional flexibility for folding or curling the proximal section 328, portions of one or more of the layers of the multilayer circuit 308 have a reduced thickness.

[0085] like Figure 4 As shown in FIG. 1 , the cross-sectional area of ​​the housing 306 can be divided into four quadrants 334A-334D and / or an upper half 336A and a lower half 336B, wherein each of the quadrants 334A-334D and the halves 336A-336B has substantially the same respective cross-sectional area. Figure 4 As shown in FIG. 1 , when the multi-layer circuit 308 is folded, at least one of the electrical leads 304 is positioned in each of the quadrants 334A-334D and the halves 336A-336B. This approach helps to fully utilize the given cross-sectional area so that a sufficient number of electrical leads 304 and electrical lead pads 316 can be used without interfering with each other, and the electrical traces within the multi-layer circuit 308 do not interfere with each other. In some embodiments, the diameter of the housing 306 is .35-1 mm (i.e., the cross-sectional area is .096-.79 mm). 2 ) and a length of 3-6 mm. In some embodiments, the diameter of the housing 306 is .45-.55 mm (ie, a cross-sectional area of ​​.16-.24 mm 2 ), and a length of 4-5 mm. In some embodiments, the housing 306 is square or rectangular. In some embodiments, the housing 306 includes a shell 338, which includes a material such as polyimide, PEEK, PTFE, FEP, polyurethane, silicone, parylene, metal (e.g., stainless steel, aluminum, titanium, nickel-based alloys, cobalt-based alloys, and the like), and an epoxy filling material within the shell 338 to maintain the position of the multi-layer circuit assembly 302 in the housing 306. In some embodiments, the entire housing 306 includes epoxy material.

[0086] Figure 7-Figure 8 shows that it can be used in medical devices (such as Figure 1The sensor assembly 700 is used in a medical device 104 in a medical device. For example, the sensor assembly 300 can be positioned within the medical device (e.g., at or near the distal end of the medical device). The sensor assembly 700 includes a multi-layer circuit assembly 702 electrically coupled to an electrical lead 704 and positioned within a housing 706.

[0087] The multilayer circuit assembly 702 includes a multilayer circuit 708 extending between a proximal end (not shown) and a distal end 710. The multilayer circuit 708 includes a flexible substrate 712, a first mask layer 714A, a second mask layer 714B, electrical lead pads 716, electrical mounting pads 718, and electrical traces (not shown) that electrically couple certain electrical lead pads 716 to certain electrical mounting pads 718. The first mask layer 714A and the second mask layer 714B are positioned on opposite sides of the flexible substrate 712. In some embodiments, the thickness of the multilayer circuit 708 is approximately 50 microns.

[0088] The multi-layer circuit assembly 702 further includes a first magnetic field sensor 720A, a second magnetic field sensor 720B, and a third magnetic field sensor 720C, and a first sensor circuit 722A, a second sensor circuit 722B, and a third sensor circuit 722C. Figure 7-Figure 8 As shown in , magnetic field sensors 720A-720C and sensor circuits 722A-722C can be implemented on separate dies and positioned adjacent to each other. In such embodiments, magnetic field sensors 720A-720C and sensor circuits 722A-722C can be electrically and communicatively coupled together. In certain embodiments, corresponding magnetic field sensors 720A-720C and sensor circuits 722A-722C can be implemented on the same die or substrate (e.g., a monolithic design). For example, magnetic field sensors 720A-720C can be manufactured on top of corresponding sensor circuits 722A-722C.

[0089] The magnetic field sensors 720A-720C may include sensors (such as inductive sensing coils) and / or various sensing elements, such as MR sensing elements (e.g., AMR sensing elements, GMR sensing elements, TMR sensing elements, Hall effect sensing elements, CMR sensing elements, EMR sensing elements, spin Hall sensing elements, and the like), GMI sensing elements, and / or fluxgate sensing elements. The MR sensing elements are configured to sense magnetic fields, such as Figure 1 The multilayer circuit assembly 702 may also feature other types of sensors, such as temperature sensors, ultrasonic sensors, etc. The sensor signals generated by the magnetic field sensors 720A-720C may be transmitted from the sensor assembly 700 to a controller wirelessly or via one or more conductors, such as Figure 1A magnetic field controller 114 is provided.

[0090] In some embodiments, the magnetic field sensors 720A-720C are arranged in a two-axis, six-degree-of-freedom arrangement. In such an embodiment, the first magnetic field sensor 720A and the second magnetic field sensor 720B are oriented so that their primary sensing directions are aligned along the longitudinal axis 724 (e.g., the X-axis) of the sensor accessory 700. The third magnetic field sensor 720C is oriented so that its primary sensing direction is aligned along an axis (e.g., the Y-axis) that is orthogonal to the longitudinal axis 724. In some embodiments, the magnetic field sensors 720A-720C are arranged in a three-axis, six-degree-of-freedom arrangement. In such an embodiment, the primary sensing directions of the magnetic field sensors are orthogonal to each other. Although the first magnetic field sensor 720A, the second magnetic field sensor 720B, and the third magnetic field sensor 720C and the first sensor circuit 722A, the second sensor circuit 722B, and the third sensor circuit 722C are shown as being oriented substantially in the same plane, the magnetic field sensors may be oriented in different planes (e.g., orthogonal planes). Although Figure 7-Figure 8 Magnetic field sensors 720A-720C and sensor circuits 722A-722C are shown positioned on the same side of multilayer circuit 708, but magnetic field sensors 720A-720C and sensor circuits 722A-722C can be distributed between the two sides of multilayer circuit 708. In some embodiments, multilayer circuit assembly 702 includes only two magnetic field sensors with different main sensing directions. In some embodiments, one or more of the magnetic field sensors are dual-axis or tri-axis sensors with two or three main sensing directions, respectively. The first, second, and third magnetic field sensors 720A-720C are configured to generate responsive sensing signals in response to a magnetic field. The sensing signals are used to determine the position and orientation of sensor assembly 700. In some embodiments, the magnetic field sensors are arranged in a single-axis, five-degree-of-freedom arrangement.

[0091] In some embodiments, the magnetic field sensors 720A-720C and / or the sensor circuits 722A-722C are electrically coupled to the respective electrical mounting pads 718 via wire bonds 726. In some embodiments, the magnetic field sensors 720A-720C and / or the sensor circuits 722A-722C are electrically coupled to the respective electrical mounting pads 718 via a flip chip approach, through silicon vias, or fan-out wafer level packaging. As previously mentioned, the electrical mounting pads 718 are electrically coupled to the electrical lead pads 716 via electrical traces.

[0092] In some embodiments, when magnetic field sensors 720A-720C are arranged in a dual-axis or tri-axis arrangement, multi-layer circuit 708 includes six or seven electrical lead pads 716, and multi-layer circuit assembly 702 includes six or seven electrical leads 704. In a dual-axis arrangement, multi-layer circuit assembly 702 may include six electrical lead pads 716: one ground lead pad, one bias lead pad, one positive X-axis signal lead pad, one negative X-axis signal lead pad, one positive Y-axis signal lead pad, and one negative Y-axis signal lead pad. In a tri-axis arrangement, multi-layer circuit assembly 702 may include eight or nine electrical lead pads: one ground lead pad, one bias lead pad, one positive X-axis signal lead pad, one negative X-axis signal lead pad, one positive Y-axis signal lead pad, one negative Y-axis signal lead pad, one positive Z-axis signal lead pad, one negative Z-axis signal lead pad, and a reset lead pad. In certain embodiments, the electrical leads 704 include a conductive material (eg, copper), and the electrical lead pads 716 are spaced apart from each other at the proximal end for adequate electrical isolation.

[0093] like Figure 7-Figure 8 As shown in FIG. 7 , the multilayer circuit 708 is not like Figure 3-Figure 6 Instead of being folded or rolled, the multilayer circuit 708 is able to fit the electrical lead pads 716 into a limited cross-sectional area by distributing the electrical lead pads 716 between the two sides of the flexible substrate 712. In addition, because the multilayer circuit 708 is not folded or rolled, it is not as convenient as the multilayer circuit 308 of FIG. Figure 3-Figure 6 Compared to the multilayer circuit 308 of FIG. 1 , the multilayer circuit 708 can be rigid and utilize a more rigid printed circuit board. During manufacturing, the electrical leads 704 can be coupled to the electrical lead pads 716 via a variety of methods (e.g., reflow solder (so that the solder melts and solidifies), welding (laser and the like), tape automated bonding, thermal compression, ultrasonic compression, anisotropic conductive film, soldering, and the like) to mechanically and electrically couple the electrical leads 704 and the electrical lead pads 716. As mentioned above, the magnetic field sensors 720A-720C and the sensor circuits 722A-722C can be electrically coupled to the electrical mounting pads 718 via wire bonding, flip chip, through silicon vias, fan-out wafer level packaging, and the like.

[0094] like Figure 8 As shown in FIG. 1 , the cross-sectional area of ​​the housing 706 can be divided into four quadrants 726A-726D and / or an upper half 728A and a lower half 728B, wherein each of the quadrants 726A-726D and the halves 728A-728B has substantially the same respective cross-sectional area. Figure 8, in such a configuration, at least one of the electrical leads 704 is positioned in each of the quadrants 726A-726D and the halves 728A-728B. This approach helps to fully utilize the given cross-sectional area so that a sufficient number of electrical leads 704 and electrical lead pads 716 can be used without interfering with each other, and electrical traces within the multi-layer circuit 708 do not interfere with each other. In some embodiments, the diameter of the housing 706 is .35-1 mm (i.e., the cross-sectional area is .096-.79 mm 2 ) and a length of 3-6 mm. In some embodiments, the diameter of the housing 706 is .45-.55 mm (ie, a cross-sectional area of ​​.16-.24 mm 2 ), and a length of 4-5 mm. In some embodiments, the housing 706 is square or rectangular. In some embodiments, the housing 706 includes a shell 730, which includes a material such as polyimide, PEEK, PTFE, FEP, polyurethane, silicone, parylene, metal (e.g., stainless steel, aluminum, titanium, nickel-based alloys, cobalt-based alloys, and the like), and an epoxy filling material to maintain the position of the multi-layer circuit assembly 702 in the housing 706. In some embodiments, the entire housing 706 includes an epoxy material.

[0095] Figure 9-10 shows that it can be used in medical devices (such as Figure 1 Sensor assembly 900 for use in a medical device 104 in a medical device. For example, sensor assembly 300 can be positioned within a medical device (e.g., at or near a distal end of the medical device). Sensor assembly 900 includes a multi-layer circuit assembly 902 electrically coupled to electrical leads 904 and positioned within a housing 906.

[0096] The multilayer circuit assembly 902 includes a multilayer circuit 908 extending between a proximal end (not shown) and a distal end 910. The multilayer circuit 908 includes a flexible substrate 912, a first mask layer 914A, a second mask layer 914B, electrical lead pads 916, electrical mounting pads 918, and electrical traces (not shown) that electrically couple certain electrical lead pads 916 to certain electrical mounting pads 918. The first mask layer 914A and the second mask layer 914B are positioned on opposite sides of the flexible substrate 912. In some embodiments, the thickness of the multilayer circuit 908 is approximately 50 microns.

[0097] The multilayer circuit assembly 902 further includes a first magnetic field sensor 920A, a second magnetic field sensor 920B, and a third magnetic field sensor 920C, and a first sensor circuit 922A, a second sensor circuit 922B, and a third sensor circuit 922C. Figure 3-Figure 6As shown in , magnetic field sensors 920A-920C and sensor circuits 922A-922C can be implemented on separate dies and positioned adjacent to each other. In such embodiments, magnetic field sensors 920A-920C and sensor circuits 922A-922C can be electrically and communicatively coupled together. In certain embodiments, corresponding magnetic field sensors 920A-920C and sensor circuits 922A-922C can be implemented on the same die or substrate (e.g., a monolithic design). For example, magnetic field sensors 920A-920C can be manufactured on top of corresponding sensor circuits 922A-922C.

[0098] The magnetic field sensors 920A, 920B, and 920C may include sensors (such as inductive sensing coils) and / or various sensing elements, such as MR sensing elements (e.g., AMR sensing elements, GMR sensing elements, TMR sensing elements, Hall effect sensing elements, CMR sensing elements, EMR sensing elements, spin Hall sensing elements, and the like), GMI sensing elements, and / or fluxgate sensing elements. The MR sensing elements are configured to sense magnetic fields, such as Figure 1 The multilayer circuit assembly 902 may also feature other types of sensors, such as temperature sensors, ultrasonic sensors, etc. The sensor signals generated by the magnetic field sensors 920A-920C may be transmitted from the sensor assembly 900 to a controller wirelessly or via one or more conductors, such as Figure 1 A magnetic field controller 114 is provided.

[0099] In some embodiments, the magnetic field sensors 920A-920C are arranged in a two-axis, six-degree-of-freedom arrangement. In such an embodiment, the first magnetic field sensor 920A and the second magnetic field sensor 920B are oriented so that their primary sensing directions are aligned along the longitudinal axis 924 (e.g., the X-axis) of the sensor accessory 900. The third magnetic field sensor 920C is oriented so that its primary sensing direction is aligned along an axis (e.g., the Y-axis) that is orthogonal to the longitudinal axis 924. In some embodiments, the magnetic field sensors 920A-920C are arranged in a three-axis, six-degree-of-freedom arrangement. In such an embodiment, the primary sensing directions of the magnetic field sensors are orthogonal to each other. Although the first magnetic field sensor 920A, the second magnetic field sensor 920B, and the third magnetic field sensor 920C and the first sensor circuit 922A, the second sensor circuit 922B, and the third sensor circuit 922C are shown as being oriented approximately in the same plane, the magnetic field sensors may be oriented in different planes (e.g., orthogonal planes). Although Figure 9-10Magnetic field sensors 920A-920C and sensor circuits 922A-922C are shown positioned on the same side of multilayer circuit 908, but magnetic field sensors 920A-920C and sensor circuits 922A-922C can be distributed between the two sides of multilayer circuit 908. In some embodiments, multilayer circuit assembly 902 includes only two magnetic field sensors with different main sensing directions. In some embodiments, one or more of the magnetic field sensors are dual-axis or tri-axis sensors with two or three main sensing directions, respectively. The first, second, and third magnetic field sensors 920A-920C are configured to generate responsive sensing signals in response to a magnetic field. The sensing signals are used to determine the position and orientation of sensor assembly 900.

[0100] In some embodiments, the magnetic field sensors 920A-920C and / or sensor circuits 922A-922C are electrically coupled to respective electrical mounting pads 918 via wire bonds 926. In some embodiments, the magnetic field sensors 920A-920C and / or sensor circuits 922A-922C are electrically coupled to respective electrical mounting pads 918 via a flip chip approach, through silicon vias, or fan-out wafer level packaging. As previously mentioned, the electrical mounting pads 918 are electrically coupled to the electrical lead pads 916 via electrical traces.

[0101] In some embodiments, when magnetic field sensors 920A-920C are arranged in a dual-axis or tri-axis arrangement, multilayer circuit 908 includes six or seven electrical lead pads 916, and multilayer circuit assembly 902 includes six or seven electrical leads 904. In a dual-axis arrangement, multilayer circuit assembly 902 may include six electrical lead pads 916: one ground lead pad, one bias lead pad, one positive X-axis signal lead pad, one negative X-axis signal lead pad, one positive Y-axis signal lead pad, and one negative Y-axis signal lead pad. In a tri-axis arrangement, multilayer circuit assembly 902 may include eight or nine electrical lead pads: one ground lead pad, one bias lead pad, one positive X-axis signal lead pad, one negative X-axis signal lead pad, one positive Y-axis signal lead pad, one negative Y-axis signal lead pad, one positive Z-axis signal lead pad, one negative Z-axis signal lead pad, and a reset lead pad. In certain embodiments, the electrical leads 904 include a conductive material (eg, copper), and the electrical lead pads 916 are spaced apart from one another at the proximal end for adequate electrical isolation.

[0102] The multilayer circuit 908 includes a proximal section 928 having exposed electrical lead pads 916 and a distal section 930 having exposed electrical mounting pads 918. During manufacturing, the electrical leads 904 may be coupled to the electrical lead pads 916 via a variety of methods (e.g., solder reflow (so that the solder melts and solidifies), welding (laser and the like), tape automated bonding, thermal compression, ultrasonic compression, anisotropic conductive film, soldering, and the like) to mechanically and electrically couple the electrical leads 904 and the electrical lead pads 916. As mentioned above, the magnetic field sensors 920A-920C and the sensor circuits 922A-922C may be electrically coupled to the electrical mounting pads 918 via wire bonding, flip chip, through silicon via, fan-out wafer level packaging, and the like. After various electrical couplings are made, the proximal section 928 may be folded (e.g., curled).

[0103] like Figure 9-10 , the proximal section 928 is folded so that the multi-layer circuit 908 (and therefore the multi-layer circuit assembly 902) consumes less cross-sectional area at the proximal end of the multi-layer circuit assembly 902. In some embodiments, the proximal section 928 is folded and formed into a generally c-shape. In such embodiments, the proximal section 928 has a substantially constant bend radius throughout the length of the cross section. Fig.10 As shown in , in some embodiments, the proximal section 928 includes a first leg 930A and a second leg 930B and a bend 932 extending between the first leg 930A and the second leg 930B. The electrical lead pad 916 is positioned on the first leg 930A and the second leg 930B. The bend 932 has a substantially constant bending radius throughout its cross-sectional length, while the first leg 930A and the second leg 930B are substantially straight. In addition to folding the proximal section 928, the multilayer circuit 908 also distributes the electrical lead pads 916 between the two sides of the flexible substrate 912. For example, the multilayer circuit 908 includes four electrical lead pads 916 on a first side of the flexible substrate 912 and two electrical lead pads on an opposite side of the flexible substrate 912. As shown in FIG. Fig.10 As shown in FIG, once the multilayer circuit 908 is folded, the electrical leads 904 and the electrical lead pads 916 are positioned within the inner region and the outer region of the proximal section 928. In particular, two of the electrical lead pads 916 are positioned within the inner region of the folded proximal section 928, and four of the electrical lead pads 916 are positioned outside the inner region.

[0104] like Fig.10, only a portion of the proximal section 928 is covered by the second mask layer 914B, leaving the flexible substrate 912 exposed. Limiting the coverage of the second mask layer 914B on the proximal section 928 can provide additional flexibility for folding or curling the proximal section 928. For example, without full coverage of the second mask layer 914B (or the first mask layer 914A), the proximal section 928 can be folded with a small bending radius. In some embodiments, in order to provide additional flexibility for folding or curling the proximal section 928, portions of one or more of the layers of the multilayer circuit 908 have a reduced thickness.

[0105] like Fig.10 As shown in FIG. 1 , the cross-sectional area of ​​the housing 906 can be divided into four quadrants 934A-934D and / or an upper half 936A and a lower half 936B, wherein each of the quadrants 934A-934D and the halves 936A-936B has substantially the same respective cross-sectional area. Fig.10 As shown in FIG. 1 , when the multi-layer circuit 908 is folded, at least one of the electrical leads 904 is positioned in each of the quadrants 934A-934D and the halves 936A-936B. This approach helps to fully utilize the given cross-sectional area so that a sufficient number of electrical leads 904 and electrical lead pads 916 can be used without interfering with each other, and the electrical traces within the multi-layer circuit 908 do not interfere with each other. In some embodiments, the diameter of the housing 906 is .35-1 mm (i.e., the cross-sectional area is .096-.79 mm 2 ) and a length of 3-6 mm. In some embodiments, the diameter of the housing 906 is .45-.55 mm (ie, a cross-sectional area of ​​.16-.24 mm 2 ), and a length of 4-5 mm. In some embodiments, the housing 906 is square or rectangular. In some embodiments, the housing 906 includes a shell 938, which includes a material such as polyimide, PEEK, PTFE, FEP, polyurethane, silicone, parylene, metal (e.g., stainless steel, aluminum, titanium, nickel-based alloys, cobalt-based alloys, and the like), and an epoxy filler material to maintain the position of the multi-layer circuit assembly 902 in the housing 906. In some embodiments, the entire housing 906 includes an epoxy material.

[0106] Figure 11-Figure 12 shows that it can be used in medical devices (such as Figure 1 The sensor assembly 1100 or a portion thereof is provided for use in a medical device 104 in a medical device. For example, the sensor assembly 300 can be positioned within the medical device (e.g., at or near a distal end of the medical device). The sensor assembly 1100 includes an electrical lead 1104 (see FIG. 1 ). Fig.12 ) and positioned in housing 1106 (see Fig.12 ) within a multi-layer circuit assembly 1102. Fig.11 Multi-layer circuit assembly 1102 is shown before multi-layer circuit 1108 is formed into its final shape and before multi-layer circuit assembly 1102 is incorporated into sensor assembly 1100 .

[0107] The multilayer circuit assembly 1102 includes a multilayer circuit 1108 extending between a proximal end 1110A and a distal end 1110B. The multilayer circuit 1108 includes a flexible substrate 1112, a first mask layer 1114A, a second mask layer 1114B, electrical lead pads 1116, electrical mounting pads 1118, and electrical traces (not shown) that electrically couple certain electrical lead pads 1116 to certain electrical mounting pads 1118. The first mask layer 1114A and the second mask layer 1114B are positioned on opposite sides of the flexible substrate 1112. In some embodiments, the thickness of the multilayer circuit 1108 is approximately 50 microns.

[0108] The multilayer circuit assembly 1102 further includes a first magnetic field sensor 1120A, a second magnetic field sensor 1120B, and a third magnetic field sensor 1120C, and a first sensor circuit 1122A, a second sensor circuit 1122B, and a third sensor circuit 1122C. Figure 11-Figure 12 As shown in FIG. 1 , magnetic field sensors 1120A-1120C and sensor circuits 1122A-1122C may be implemented on separate dies and positioned adjacent to each other. In such embodiments, magnetic field sensors 1120A-1120C and sensor circuits 1122A-1122C may be electrically and communicatively coupled together. In certain embodiments, respective magnetic field sensors 1120A-1120C and sensor circuits 1122A-1122C may be implemented on the same die or substrate (e.g., a monolithic design). For example, magnetic field sensors 1120A-1120C may be fabricated on top of respective sensor circuits 1122A-1122C.

[0109] The magnetic field sensors 1120A, 1120B, and 1120C may include sensors (such as inductive sensing coils) and / or various sensing elements, such as MR sensing elements (e.g., AMR sensing elements, GMR sensing elements, TMR sensing elements, Hall effect sensing elements, CMR sensing elements, EMR sensing elements, spin Hall sensing elements, and the like), GMI sensing elements, and / or fluxgate sensing elements. The MR sensing elements are configured to sense magnetic fields, such as Figure 1The multilayer circuit assembly 1102 may also feature other types of sensors, such as temperature sensors, ultrasonic sensors, etc. The sensing signals generated by the magnetic field sensors 1120A-1120C may be transmitted from the sensor assembly 1100 to a controller wirelessly or via one or more conductors, such as Figure 1 A magnetic field controller 114 is provided.

[0110] In certain embodiments, the magnetic field sensors 1120A-1120C are arranged in a two-axis, six-degree-of-freedom arrangement. In such an embodiment, the first magnetic field sensor 1120A and the second magnetic field sensor 1120B are oriented so that their primary sensing directions are aligned along the longitudinal axis 1124 (e.g., the X-axis) of the sensor accessory 1100. The third magnetic field sensor 1120C is oriented so that its primary sensing direction is aligned along an axis (e.g., the Y-axis) that is orthogonal to the longitudinal axis 1124. In certain embodiments, the magnetic field sensors 1120A-1120C are arranged in a three-axis, six-degree-of-freedom arrangement. In such an embodiment, the primary sensing directions of the magnetic field sensors are orthogonal to each other. Although the first magnetic field sensor 1120A, the second magnetic field sensor 1120B, and the third magnetic field sensor 1120C and the first sensor circuit 1122A, the second sensor circuit 1122B, and the third sensor circuit 1122C are shown as being oriented substantially in the same plane, the magnetic field sensors may be oriented in different planes (e.g., orthogonal planes). Although Figure 11-Figure 12 Magnetic field sensors 1120A-1120C and sensor circuits 1122A-1122C are shown positioned on the same side of multi-layer circuit 1108, but magnetic field sensors 1120A-1120C and sensor circuits 1122A-1122C can be distributed between the two sides of multi-layer circuit 1108. In some embodiments, multi-layer circuit assembly 1102 includes only two magnetic field sensors with different main sensing directions. In some embodiments, one or more of the magnetic field sensors are dual-axis or tri-axis sensors with two or three main sensing directions, respectively. The first, second, and third magnetic field sensors 1120A-1120C are configured to generate responsive sensing signals in response to a magnetic field. The sensing signals are used to determine the position and orientation of sensor assembly 1100.

[0111] In some embodiments, the magnetic field sensors 1120A-1120C and / or sensor circuits 1122A-1122C are electrically coupled to respective electrical mounting pads 1118 via wire bonds 1126. In some embodiments, the magnetic field sensors 1120A-1120C and / or sensor circuits 1122A-1122C are electrically coupled to respective electrical mounting pads 1118 via a flip chip approach, through silicon vias, or fan-out wafer level packaging. As previously mentioned, the electrical mounting pads 1118 are electrically coupled to the electrical lead pads 1116 via electrical traces.

[0112] In certain embodiments, when magnetic field sensors 1120A-1120C are arranged in a dual-axis or tri-axis arrangement, multi-layer circuit 1108 includes six or seven electrical lead pads 1116, and multi-layer circuit assembly 1102 includes six or seven electrical leads 1104. In a dual-axis arrangement, multi-layer circuit assembly 1102 may include six electrical lead pads 1116: one ground lead pad, one bias lead pad, one positive X-axis signal lead pad, one negative X-axis signal lead pad, one positive Y-axis signal lead pad, and one negative Y-axis signal lead pad. In a three-axis arrangement, multilayer circuit assembly 1102 may include eight or nine electrical lead pads: a ground lead pad, a bias lead pad, a positive X-axis signal lead pad, a negative X-axis signal lead pad, a positive Y-axis signal lead pad, a negative Y-axis signal lead pad, a positive Z-axis signal lead pad, a negative Z-axis signal lead pad, and a reset lead pad. In some embodiments, electrical leads 1104 include conductive material (e.g., copper), and electrical lead pads 1116 are spaced apart from each other at proximal ends for adequate electrical isolation.

[0113] Fig.11 Multilayer circuit assembly 1102 is shown before multilayer circuit 1108 is formed into its final shape and before incorporation of multilayer circuit assembly 1102 into sensor assembly 1100. For each of electrical lead pads 1116 and electrical mounting pads 1118, first mask layer 1114A is removed so that the pad is exposed and accessible for electrical coupling to the corresponding electrical lead 1104 and wire bond 1126, etc.

[0114] The multilayer circuit 1108 includes a proximal section 1128 having exposed electrical lead pads 1116 and a distal section 1130 having exposed electrical mounting pads 1118. During manufacturing, the electrical leads 1104 may be coupled to the electrical lead pads 1116 via a variety of methods (e.g., solder reflow (so that the solder melts and solidifies), welding (laser and the like), tape automated bonding, thermal compression, ultrasonic compression, anisotropic conductive film, soldering, and the like) to mechanically and electrically couple the electrical leads 1104 and the electrical lead pads 1116. As mentioned above, the magnetic field sensors 1120A-1120C and the sensor circuits 1122A-1122C may be electrically coupled to the electrical mounting pads 1118 via wire bonding, flip chip, through silicon via, fan-out wafer level packaging, and the like. After the various electrical couplings are made, the proximal section 1128 may be folded (e.g., curled).

[0115] like Fig.12 , proximal section 1128 is folded so that multi-layer circuit 1108 (and therefore multi-layer circuit assembly 1102) consumes less cross-sectional area at proximal end 1110A of multi-layer circuit assembly 1102. In some embodiments, proximal section 1128 is folded and formed into a shape that at least partially mimics the shape of housing 1106. In such embodiments, a portion of proximal section 1128 has a substantially constant bend radius throughout the length of the cross section. Fig.11 As shown in FIG. 1 , in some embodiments, the proximal section 1128 includes a leg and a bend. The electrical lead pads 1116 are positioned on the leg and the bend. In particular, four of the electrical lead pads 1116 are positioned on the bend, while two of the electrical lead pads 1116 are positioned on the leg. The bend has a substantially constant bend radius throughout its cross-sectional length, while the leg is substantially straight. Fig.12 As shown in FIG. 1 , once the multi-layer circuit 1108 is folded, the electrical leads 1104 and the electrical lead pads 1116 are positioned within the interior region of the proximal section 1128 .

[0116] like Fig.11 As shown in FIG. 1 , the proximal section 1128 has a length L extending along the longitudinal axis 1124. In some embodiments, to provide additional flexibility for folding or curling the proximal section 1128, portions of one or more of the layers of the multilayer circuit 1108 have a reduced thickness or may be removed.

[0117] like Fig.11As shown in FIG. 1 , the cross-sectional area of ​​the housing 1106 can be divided into four quadrants 1134A-1134D and / or an upper half 1136A and a lower half 1136B, wherein each of the quadrants 1134A-1134D and the halves 1136A-1136B has substantially the same respective cross-sectional area. Fig.11 As shown in FIG. 1 , when the multi-layer circuit 1108 is folded, at least one of the electrical leads 1104 is positioned in each of the quadrants 1134A-1134D and the halves 1136A-1136B. This approach helps to fully utilize the given cross-sectional area so that a sufficient number of electrical leads 1104 and electrical lead pads 1116 can be used without interfering with each other, and the electrical traces within the multi-layer circuit 1108 do not interfere with each other. In some embodiments, the diameter of the housing 1106 is .35-1 mm (i.e., the cross-sectional area is .096-.79 mm). 2 ) and has a length of 3-6 mm. In some embodiments, the diameter of the housing 1106 is .45-.55 mm (ie, the cross-sectional area is .16-.24 mm 2 ), and a length of 4-5 mm. In some embodiments, the housing 1106 is square or rectangular. In some embodiments, the housing 1106 includes a shell 1138, which includes a material such as polyimide, PEEK, PTFE, FEP, polyurethane, silicone, parylene, metal (e.g., stainless steel, aluminum, titanium, nickel-based alloys, cobalt-based alloys, and the like), and an epoxy filler material to maintain the position of the multi-layer circuit assembly 1102 in the housing 1106. In some embodiments, the entire housing 1106 includes an epoxy material.

[0118] Various modifications and additions may be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments described above relate to specific features, the scope of the present invention also includes embodiments with different combinations of features and embodiments that do not include all of the described features. Therefore, the scope of the present invention is intended to include all such substitutions, modifications and variations that fall within the scope of the claims, and all equivalents thereof.

Claims

1. A sensor accessory, comprising: a multi-layer circuit extending along a longitudinal axis between a proximal end and a distal end, the multi-layer circuit including a plurality of electrical pads positioned at the proximal end; a first magnetic field sensor coupled to the multi-layer circuit and having a primary sensing direction aligned with the longitudinal axis; as well as A second magnetic field sensor is coupled to the multi-layer circuit and oriented relative to the first magnetic field sensor such that the second magnetic field sensor has a primary sensing direction aligned with an axis orthogonal to the longitudinal axis.

2. The sensor assembly according to claim 1, wherein: The multilayer circuit includes a flexible substrate layer, wherein a first subset of the plurality of electrical pads is positioned on a first side of the flexible substrate layer, and wherein a second subset of the plurality of electrical pads is positioned on a second side of the flexible substrate layer opposite the first side.

3. The sensor accessory according to any one of claims 1 to 2, wherein: The proximal section of the multilayer circuit is folded such that at least one of the plurality of electrical pads is positioned on a different plane than the other plurality of electrical pads.

4. The sensor assembly according to any one of claims 1 to 3, wherein: The proximal section of the multi-layer circuit is generally c-shaped.

5. The sensor assembly according to any one of claims 3 to 4, wherein: The proximal section includes a folded portion that is only partially covered by the mask layer, such that a portion of the flexible substrate layer is exposed.

6. The sensor assembly according to any one of claims 1 to 5, wherein: The multi-layer circuit includes six to nine electrical pads at the proximal end.

7. The sensor assembly according to any one of claims 1 to 6, further comprising: A plurality of electrical leads are each electrically coupled to one of the plurality of electrical pads.

8. The sensor assembly according to any one of claims 1 to 7, further comprising: A housing surrounds the multi-layer circuit, the first magnetic sensor, and the second magnetic sensor.

9. The sensor assembly according to claim 8, wherein: The housing includes four quadrants of substantially equal size, wherein at least one electrical lead is positioned within each of the four quadrants.

10. The sensor assembly according to any one of claims 8 to 9, wherein: The shell is cylindrical, polygonal or rectangular.

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