Patent Description:
Most monitors measure irregular heart-beats or any other irregular or abnormal physiological activity. An ambulatory electrocardiogram (AECG), which is consistently worn anywhere between <NUM> hours to a week or more, monitors electrocardiogram (ECG) data.

Similarly, blood pressure (BP) monitors are used for hypertension management and cardiac monitoring. The monitors generate alarms, which may indicate an, or varying levels of, emergency in response to detection of an abnormal condition. However, often there are cases when a sensor detects what appears to be abnormal physiological activity due to a change in the patient's position or due to the patient's movement, yet the patient is actually healthy and his or her health status does not warrant an alarm. This may be especially true for ambulatory patients. For example, a person using a BP monitor may be exercising when the BP levels are detected as being abnormal. Similarly, an AECG monitor may falsely raise an alarm when the heart-beat of a wearer appears to be abnormal during exercising.

Even though exercise may skew physiological monitoring, low acuity patients need to be active to speed their recovery. Therefore, it may be desirable to be able to monitor their movements over a period of time. Some monitors combine information about different types of physiological data to conclude whether a wearer of the monitor(s) (or patient) is experiencing an abnormal health condition. For example, several models of BP monitors
from various manufacturers have been developed with an added function of irregular heartbeat detection. However, these monitors are also prone to providing false positives when an otherwise healthy person is in motion. In addition to exercising, false positives may also be generated due to other external events, such as any other type of physical stress for example while lifting an object, work, fatigue, and changes in environmental conditions.

Sometimes, even changing posture while sleeping may generate a false positive.

There is therefore a need to combine motion detection information, such as through motion sensors, to be able to effectively monitor physiological data and reduce or eliminate false positives generated by physiological monitors. There is also a need to correlate motion and/or positional information of a patient with any other physiological data, which may be monitored continuously, regularly, or in real time, so as to enhance the reliability and accuracy of physiological data monitors and improve diagnosis. Current physiological monitoring systems, such as AECG monitors, are unable to effectively integrate motion detection information. The monitoring systems fail to effectively combine a motion detector within existing components without having to introduce circuit-level changes or other forms of system-related modifications. Therefore, there is a need for a simple method and system that may be seamlessly integrated with existing monitoring systems, to add the capability of motion detection. It is also desirable to combine motion detection information with the physiological monitoring information to provide users with correlated data.

Many communication methods exist where one electronic device can communicate to another or several other devices over multiple wires. Communication methods are also needed to combine motion sensor data with devices for other purposes, in order to minimize the cost and apparatus needed for the combination. For some designs, however, it becomes more practical to minimize the number of wires necessary for communication. Devices are known to use a single-wire bus for bi-directional communication. The single wire connection used for bi-directional communication can interconnect two or more devices. A master device is known to be connected to one or more slave devices for communication of data and for slave device(s) to draw power from the master device. A system is needed that enables efficient, low-cost, and reliable communication between a motion detecting device and any other physiological monitoring device.

<CIT> discloses a physical monitoring system for monitoring and measuring a patient's respiration. The system includes one or more resistive or inductive respiration belts, an electronic monitoring device with a processor programmed to compute respiration and a module retainer for accommodating the electronic monitoring device and securing the electronic monitoring device to the one or more resistive or inductive respiration belts. The system further includes electrocardiogram, ECG, electrodes attached to or embedded in the one or more resistive or inductive respiration belts. The ECG electrodes are connected with the electronic monitoring module via wires passing through the belts. The system can further include an accelerometer integrated with one or more of the ECG electrodes that are attached to or embedded in the one or more resistive or inductive respiration belts.

<CIT> discloses techniques for detection and treatment of myocardial ischemia that monitor both the electrical and dynamic mechanical activity of the heart to detect and verify the occurrence of myocardial ischemia. The occurrence of myocardial ischemia can be detected by monitoring changes in an electrical signal such as an ECG or EGM, and changes in dynamic mechanical activity of the heart that are sensed by an accelerometer sensor. The heart acceleration signal can be obtained from a single- or multiple-axis accelerometer and/or a pressure sensor deployed within or near the heart. The techniques correlate contractility changes detected by an accelerometer or pressure sensor with changes in the ST electrogram segment detected by the electrodes.

<CIT> discloses a monitor including cardiac and movement sensors responsive to a user's heart beat and a user's movement. The monitor includes a processor coupled to the sensors for generating heart-rate or other cardiac data and user movement or activity data. These data can be stored in a memory and used to analyse the relationship between heart rate and physical exertion.

<CIT> discloses a connector including a housing, a female snap connector member carried by the housing and configured to mechanically and electrically connect to a male snap connector member of an electrode, a three-axis accelerometer carried by the housing and configured to sense proper acceleration of the connector, and a microprocessor in electrical communication with the snap connector and with the accelerometer. The microprocessor is configured to receive cardiac activity data from the electrode, to receive proper acceleration data from the accelerometer, and to correlate the cardiac activity data to the proper acceleration data to define processed data.

<CIT> discloses a system including an electrocardiograph, a plurality of sensors communicatively coupled with the electrocardiograph, wherein each of the plurality of sensors comprises an electrode capable of detecting electrical impulses generated by a patient's body and transmitting signals indicative of detected electrical impulses to the electrocardiograph. The system can also includes a motion detection feature communicatively coupled with the electrocardiograph. The motion detection feature is capable of detecting movement of the patient's body and providing signals indicative of detected movement to the electrocardiograph. The electrocardiograph is capable of: detecting a particular type of patient motion and/or patient position based on the signals indicative of the detected motion; providing output based on the signals indicative of the detected electrical impulses; and providing output based on the signals indicative of the detected movement.

The present specification discloses a physiological lead wire configured to monitor a motion of a person and to monitor a physiological parameter of the person according to the appended claims <NUM>-<NUM>.

The present specification also discloses an electrocardiogram monitoring system according to the appended claims <NUM>-<NUM>.

The present specification also discloses a method according to the appended claims <NUM>-<NUM>.

The aforementioned and other embodiments of the present specification shall be described in greater depth in the drawings and detailed description provided below.

These and other features and advantages of the present specification will be appreciated, as they become better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:.

In various embodiments, the present specification provides methods and systems to seamlessly integrate a motion detection system with existing physiological monitoring system. The motion detection system monitors changes in position and/or movement of a wearer of the physiological monitoring system. The monitored changes may be correlated with other physiological monitoring data to identify physiological abnormalities and aid in improving diagnosis. A single wire communication system enables interfacing between the position and/or movement sensing device and an existing or conventional physiological monitor. Embodiments of the present specification provide a motion sensor system that can be embedded within a connecting wire that has the form and structure of an ECG lead wire. The connecting wire is compatible with a monitoring device, such as an ECG monitoring device. The connecting wire is connected similar to and in addition to other ECG lead wires that measure cardiac signals, to a physiological monitoring device. The connecting wire is used for providing power to the motion sensor system, which is integrated into the distal body of the ECG lead wire, and supporting bi-directional communication between the motion sensor system and the monitoring device. In alternative embodiments, the connecting wire with motion sensor system is compatible with any other physiological monitoring device, in addition to an ECG monitoring device. In embodiments, the motion sensor information is combined with information from one or more other physiological sensors to identify abnormalities and improve diagnosis.

In the description and claims of the application, each of the words "comprise" "include" and "have", and forms thereof, are not necessarily limited to members in a list with which the words may be associated. It should be noted herein that any feature or component described in association with a specific embodiment may be used and implemented with any other embodiment unless clearly indicated otherwise.

Embodiments of the present specification provide a connecting wire capable of connecting to a physiological monitoring device, such as an ECG monitor, also termed herein
as ECG device or ECG monitoring device. Embodiments of the connecting wire are described below with respect to <FIG>, <FIG>, <FIG>, and <FIG>. In an embodiment, the ECG device is a system that senses and analyses ECG signals by recording electrical activity of the heart. The monitoring is performed over a period of time using electrodes that are placed on the skin of a subject/person, such as a patient or other individual. In embodiments, the person is a patient or any other living being that is under observation for monitoring by the systems of the present specification. The ECG device typically interfaces with the electrodes through a connecting lead wire (ECG lead wire). The lead wire comprises an attachment mechanism at one end (proximal) for connection to the electrode(s) that are positioned on the subject's skin. The opposite end (distal) of the lead wire comprises a plug that interfaces with the ECG device. The heart muscle's electrophysiological pattern of depolarizing and repolarizing is measured and viewed in the form of a graph of voltage versus time (electrocardiogram). The electrocardiogram can be viewed on a screen attached to the ECG device, and/or can be printed on paper.

Ambulatory ECG devices use a small monitoring device worn by the subject which transmits monitored data from the device to a distant monitoring station using wireless communication. The device itself records, analyses, and communicates ECG data. Hardware components in the device enable sensing and storage, while software elements enable processing of data.

Sometimes hemodynamic monitoring is performed simultaneously with cardiac monitoring. Hemodynamic monitoring is usually performed using hydraulic circuits that monitor properties of blood flow. Some monitors combine respiration monitoring with ECG monitoring and/or hemodynamic monitoring, or just blood pressure (BP) monitoring. Respiration monitoring devices indicate respiration data like respiration rate, amplitude, and other characteristics. Most of these and other physiological monitoring devices receive the data concerning their objective, but also tend to receive noise that may arise due to motion of the subject. The motion data, when combined with other physiological monitoring data provides crucial diagnostic information about the subject.

Embodiments of the present specification can be configured to interface with an ECG device, a respiration monitoring device, a BP monitoring device, any other physiological monitoring device, or a combination of two or more of these devices. For instance, embodiments could be used on a patient who is wearing a Non-Invasive BP (NIBP) cuff or an SpO<NUM> sensor. The motion information derived from embodiments of the present specification would be used to provide more context to the collected NIBP or SpO<NUM> data, such as whether the patient is sitting up or active at the time of the reading. While some embodiments of systems of the present specification are described in the context of an ECG device (as the systems attach similarly to ECG electrodes and can be attached to a monitor in the same manner as an ECG lead wire, such as through a combiner (Yoke) cable or directly to the monitor), the systems of the present specification do not rely on any of the ECG components to operate. Embodiments of the present specification provide a low cost, portable option to additionally monitor position and movement-related data of a subject over a single wire for power and data, and combine the motion data with the other physiological data, in order to improve medical diagnosis as well as determine health or fitness levels.

<FIG> illustrates a connecting wire <NUM> comprising a motion sensing system, in accordance with some embodiments of the present specification. Wire <NUM> has two opposing ends including a connector/plug <NUM> at a first (distal) end and a receptacle <NUM> at a second (proximal) end. In one implementation, plug <NUM> is similar to the plug of an ECG lead wire <NUM> and therefore compatible with a conventional ECG monitor. Additionally, plug <NUM> can interface with a device <NUM>. In one embodiment device <NUM> is an ECG device, and plug <NUM> connects to the ECG device similarly to the manner in which an ECG lead wire <NUM> interfaces with device <NUM>. Accordingly, the present invention is directed toward a lead wire having a connector at one end that is compatible with a connection port of a conventional ECG monitoring device, a connection port of a conventional respiration monitoring device, a connection port of a conventional SpO<NUM> monitoring device, or a connection port of a conventional BP monitoring device such that the connector is structurally similar to a connector of a conventional ECG lead wire, a connector of a conventional respiration sensor, a connector of a conventional SpO<NUM> sensor, or a connector of a conventional blood pressure cuff, none of which have a motion sensor integrated therein.

The electrocardiogram monitoring system of <FIG>, according to embodiments of the present specification is configured to monitor a motion of a person and to monitor electrical signals generated by the person's heart. The ECG monitoring device <NUM> receives data indicative of the electrical signals from one or more ECG lead wires, including but not limited to lead wire <NUM> and motion sensor lead <NUM>. Additionally, the motion sensor lead <NUM> provides data indicative of the motion of the person. Device <NUM> includes multiple ports <NUM> where at least one of the ports is used to connect to the motion sensor lead <NUM>. The receptacle <NUM>, positioned at the second (proximal) end of the motion sensor lead <NUM>, attaches to the patient and includes an electrode and a motion detector to acquire positional and movement information of the patient and transmit the information over the motion sensor lead <NUM>. One or more of the other remaining ports <NUM> on device <NUM> connect to one or more lead wires <NUM>, which do not include a motion detector.

In one implementation receptacle <NUM> is configured similar to a snap-attach receptacle of ECG lead wire <NUM>. A snap connector, also known as a pinch clip connector, may be attached to the body of a subject. The subject could be a patient, or any other being who is a wearer of the monitoring system and is to be monitored by the various embodiments of the present specification. Receptacle <NUM> may use the ECG adhesive snaps as a way to attach to the patient's body. In embodiments, the position or placement of receptacle <NUM> on the patient's body is independent of the placement of any ECG electrode. In some embodiments, optimal locations for placement of receptacle <NUM> are suggested to the patient, which allow for better detection of respiration activity (used to verify respiratory data or to signal breathing difficulty or stress).

In one embodiment, ECG adhesive pads are used to attach receptacle <NUM> to the subject. In various embodiments, receptacle <NUM> is configured in a manner similar to any type of an ECG electrode connector, such as but not limited to a wire dumbbell connector, a locking slot connector, or a keyhole connector. In embodiments, at least one motion sensor system is embedded in proximity to receptacle <NUM>, and preferably within the housing of the receptacle <NUM>. In one embodiment, a housing at the second end of wire <NUM> a motion sensor positioned within the receptacle <NUM>. Connecting wire <NUM> is uniquely configured to communicate motion detection data from receptacle <NUM> to plug <NUM>, which may be further recorded and/or processed by separate circuits within device <NUM>. Connecting wire <NUM> provides a single path for powering the motion sensing device in receptacle <NUM> and enabling bi-directional communication between the motion sensing system and device <NUM>. In embodiments, the data collected through the motion sensor system is correlated with data from an ECG monitor and/or other physiological monitoring systems, such as respiration data and blood pressure (BP) data.

In an embodiment, an adapter cable is used to connect multiple motion sensor systems to a physiological monitoring system, such as device <NUM> shown in <FIG>. A plug portion of the adapter is configured to connect to a specific device <NUM> and may include any safety feature or unique/specialized aspect required to allow plug <NUM> to connect with wire <NUM>. Multiple receptacles are electrically coupled to device <NUM> through the adapter cable, plug <NUM>, and wire <NUM>. <FIG> illustrates an adapter cable <NUM> used to connect multiple wires to device <NUM> of <FIG>, in accordance with some embodiments of the present specification. Plug <NUM> connects to a connector 112a of adapter <NUM>, while another connector portion 112b of adapter <NUM> is available to connect another wire, such as another motion sensor system. Additionally, <FIG> illustrates an alternative embodiment of a device 110a that includes a separate connector <NUM> to connect plug <NUM>. Connector <NUM> may be provided in addition to the conventional connectors for interfacing with physiological monitoring device 110a. Connector <NUM> may also interface with an adapter <NUM> to connect with multiple sensors. Accordingly, connector comprises a first connector portion <NUM> configured to connect to a connector port of a conventional ECG monitoring device, a connection port of a conventional respiration monitoring device, or a connection port of a conventional BP monitoring device, a wire extending therefrom and being split into two or more prongs, where each prong leads to a port (112a, 112b, etc.) configured to receive a connector portion of an ECG lead wire, a cable of a respiration sensor, or a cable of a blood pressure cuff. It should be appreciated that while <FIG> shows a two-pronged connection, there could be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> prongs, or any whole number increment therein.

<FIG> is a flowchart showing exemplary process steps for monitoring both a motion of a person and electrical signals generated by the person's heart, in accordance with some embodiments of the present specification. The person is a patient or any other living being that is under observation for monitoring by the systems of the present specification. With reference to both <FIG> and <FIG>, at step <NUM>, the person, a physician or any other care provider for the person, acquires a monitoring device, such as device <NUM>, configured to receive data indicative of the electrical signals and data indicative of the motion of the person. The monitoring device <NUM> includes two or more ports <NUM> that are used to connect ECG lead wires such as lead wire <NUM>, which does not include a motion detector, and wire <NUM> which includes a motion detector, in their respective receptacles. Each of the two or more ports <NUM> of device <NUM> are structurally equivalent and are configured to receive a same shaped connector. At step <NUM>, a first ECG lead wire, such as wire <NUM>, is connected to a first port. In embodiments, wire <NUM> does not include a motion detector. The first port can be any one of the two or more ports <NUM> on device <NUM>. A first end of the wire <NUM> includes a connector configured to connect to the port of device <NUM>. A second end of the wire <NUM> includes a receptacle configured to attach to the person. The receptacle includes an electrode and does not comprise a motion detector. At step <NUM>, the electrode of first ECG lead wire is attached to the person at a suitable location on the body of the person. At step <NUM>, a second ECG lead wire, such as wire <NUM>, is connected to a second port of the two or more ports <NUM> on device <NUM>. The second ECG lead wire has a first end with a connector, such as plug <NUM>, configured to the corresponding port on device <NUM>. A second end of the wire <NUM> has a receptacle, such as receptacle <NUM>, which includes an electrode and a motion detector, configured to attach to the person. The motion detector is configured to acquire positional and movement information of the person and transmit the positional and movement information over the second ECG lead wire (wire <NUM>) to the monitoring device <NUM> when it is activated. Once device <NUM> is activated, wire <NUM> channels power to the motion detector and to transmit data to and from the motion detector. At step <NUM>, the electrode of second ECG lead wire is attached to the person in a manner similar to any other ECG lead wire, such as wire <NUM>. In some embodiments, a third ECG lead wire is attached to the device <NUM> at third port of the two or more ports <NUM>. The third ECG lead wire is similar to the first ECG lead wire <NUM>, and does not include a motion detector. A receptacle of the third wire is attached to the person similar to the first wire <NUM>. In some embodiments, a fourth ECG lead wire is attached to the device <NUM> at yet another one of its ports. The fourth ECG lead wire is similar to the first ECG lead wire <NUM> and the third wire, and does not include a motion detector. A receptacle of the fourth wire is attached to the person similar to the first wire <NUM>. At step <NUM>, the monitoring device <NUM> is activated. The monitoring device <NUM> is activated by enabling power supply to operate the device <NUM>, and optionally by selecting one or more options through a user interface such as buttons, to activate the device <NUM>. At step <NUM>, the monitoring device <NUM> records data indicative of the electrical signals and data indicative of the motion of the person.

The conventional physiological monitoring devices record and analyze data pertaining to their intended physiological parameter. Integration of real-time physiological data with position and/or movement-related data can be more effective in determining changes in the physiology of the subject. Physiological data can be monitored as a result of change in posture or movement of the subject.

<FIG> illustrates an orthographic view of a receptacle <NUM> shown in <FIG>, in accordance with some embodiments of the present specification. Receptacle <NUM> includes a housing <NUM> that encompasses components of an integrated motion sensor system <NUM>. A lead connector <NUM> is located at the distal end of a connecting wire <NUM> within a portion of the housing <NUM> that interfaces with an electrode connector, analogous to an ECG electrode connector for the purpose of attaching receptacle <NUM> to the body of the subject. Motion sensor system <NUM> may comprise multiple components placed on a printed circuit board (PCB), and including elements that detect and process position and movement-related data. Accordingly, in one embodiment, the present invention is directed to a ECG electrode having a housing, an electrode embedded into, and exposed outside of, the housing, and a motion detector integrated into the housing, proximate the electrode.

<FIG> illustrates a first portion 300a of a PCB configured to carry components of motion sensor system <NUM> shown in <FIG>, in accordance with some embodiments of the present specification. <FIG> illustrates a second portion 300b of a PCB, which is on a side opposite to the side of first portion 300a, configured to carry components of motion sensor system <NUM> shown in <FIG>, in accordance with some embodiments of the present specification. Referring simultaneously to <FIG>, the PCB (300a, 300b) is configured to be housed within a housing of a receptacle of a lead connecting wire that couples the motion sensor system to a monitoring device that stores and processes motion sensor data alone, or in combination with other physiological monitoring data. In embodiments, the PCB (300a, 300b) is sized in order to fit within the housing of the receptacle. In one embodiment, the PCB (300a, 300b) is <NUM> inches (<NUM>) long and <NUM> inches (<NUM>,<NUM>) wide, with electrical and electronic components on both sides. In some embodiments, electrical 1pads <NUM> on the PCB (300a, 300b) are configured to solder the ground and power/communication wires to the PCB (300a, 300b).

The connecting wire may be soldered to one of the electrical pads <NUM> to enable communication between PCB (300a, 300b) components and a power source and physiological data monitoring device. Power from the source may be communicated over the connecting wire and received by a power converter <NUM>. Power converter <NUM> is configured to drop the power on the cable down to a recommended chip voltage and to remove the fluctuation of the power due to the signalling, and thereby power the electronic components of PCB (300a, 300b). A processor <NUM> is configured to both process sensor data and facilitate communication to and from the physiological monitoring device. A motion sensor <NUM> detects position and movement-related data and provides the data to processor <NUM>. In some embodiments, motion sensor <NUM> is a multi-axis accelerometer. In one embodiment, motion sensor <NUM> is a tri-axis accelerometer. In various embodiments, motion sensor <NUM> could include a '<NUM>-axis' sensor (<NUM>-axis accelerometer and <NUM>-axis gyroscope), or a '<NUM>-axis' sensor (<NUM>-axis accelerometer, <NUM>-axis gyroscope, and <NUM>-axis magnetometer). The sensors are used to provide positional and orientation information in <NUM>-axis, which could be used to determine an orientation of a patient, such as determining if a patient is facing down a corridor as opposed to across it. Given that an accelerometer will indicate a value of <NUM> straight downward (due to gravity), the accelerometer may be used to determine inclination of a patient. Quick changes in the acceleration indicated by the accelerometer may show motion of the subject,
whereas slow changes in the acceleration may indicate an inclination change (for example, sitting up or rolling on one's side). Motion sensor <NUM> is configured to detect at least one or more of a position, inclination, and movement of the subject.

Embodiments of the present specification can be configured to interface with different types of physiological monitoring devices, such as respiration monitoring devices, BP monitoring devices, and devices that monitor multiple physiological parameters but, in each case, are preferably positioned within the housing of a conventional physiological sensor positioned on the patient's body.

Embodiments of the present specification are used to monitor exercise data of the subject. Activity levels may be quantified to provide helpful indications about the exercises performed by the subject. For example, the number of steps can be monitored. Embodiments of the present specification may also be used to indicate a type and duration of one or more activities performed by the subject. For example, physiological data is combined with posture information to determine whether the subject is sitting, standing, awake, or asleep, for a healthy duration. Similarly, embodiments may be used to determine levels of inactivity. For example, a subject who is bed-ridden is monitored for duration(s) of inactivity and an alarm is generated to remind that the subject needs to be moved to avoid bed-sores, or if they have deceased. Embodiments can be used to also detect fall of a subject. Embodiments can also be used to detect movement by a subject that may be unwarranted, accidental, or unhealthy. For example, movement of a subject exiting the bed can be detected when they are not supposed to leave on their own. Embodiments can also be used to detect rapid movements, such as but not limited to seizures, tremors, epileptic episodes, shivers, rapid breathing due to discomfort, coughing, vomiting, and rolling in bed.

Embodiments of the present specification may combine respiration detection data with motion sensor data to monitor chest motion and detect apnea. Additionally, measurement of respiration characteristics can be suppressed during a healthy exercise regimen. Similarly, when combining BP measurement data, a monitoring attempt can be cancelled, delayed or retried at later time, if the subject is identified to be excessively active.

Embodiments of the present specification assist in minimizing false ECG ST Segment alarms, which may otherwise occur due to positional changes. Additionally, false ECG rhythm alarms, such as v-tach (ventricular tachycardia), v-run (ventricular run), or any other ECG parameter, due to changes in position or due to motion, are minimized. A combination of ECG data, respiration data, BP data, with the motion sensor data in accordance with the embodiments of the present specification can detect and raise an appropriate alarm if a subject has a critical condition, for example, if the heart rate is low and there is a decrease in pulse amplitude.

Referring now to <FIG>, a block diagram <NUM> of two devices that are connected using a single wire <NUM> for power and data communication is illustrated in accordance with some embodiments of the present specification. In embodiments, device <NUM> corresponds to device <NUM> (<FIG>) used for physiological monitoring, and device <NUM> corresponds to an integrated motion sensor system <NUM> (<FIG>) placed within a receptacle <NUM> (<FIG>). In embodiments, a first device <NUM> and a second device <NUM>, are respectively configured as a master device and a slave device. Device <NUM> provides power to device <NUM>, and both devices communicate with each other over wire <NUM>. In some embodiments, multiple slave devices are connected to first device <NUM>.

In one embodiment during normal operation, a first transistor <NUM> in first device <NUM> does not conduct, thus allowing power from a power source and through a power module <NUM>, through a second transistor <NUM>, and through a first resistor <NUM> to wire <NUM> and thus to any connected devices, such as device <NUM>. First device <NUM> and second device <NUM>, each have a transistor <NUM> and <NUM>, respectively, which are non-conducting. The transistor <NUM> in second device <NUM> is normally non-conducting. Therefore, the power sourced by device <NUM> over wire <NUM> to device <NUM> flows through a diode <NUM> positioned between transistor <NUM> and a power module <NUM> within device <NUM>, towards power module <NUM>. A comparator <NUM> is configured to receive power sent over wire <NUM>, within device <NUM>. Comparator <NUM> compares the input power rail to a reference voltage and outputs a 'low' to a receiving pin on a processor <NUM> of device <NUM>.

In one embodiment, for transmitting a bit from first/master device <NUM> to second/slave device <NUM>, first transistor <NUM> is moved to a conducting state which switches transistor <NUM> to a non-conducting state. The side of first resistor <NUM> that is connected to wire <NUM>, is pulled 'low' through conducting transistor <NUM>. On the other side of wire <NUM>, in second device <NUM>, comparator <NUM> senses the input supply going 'low' and switches the receiving pin on processor <NUM> to 'high'. In some embodiments, 'low' and 'high' signify a level of voltage, which can be interpreted by digital circuits as binary data. In some embodiments the 'high' and 'low' states can be opposite - that is what is specified in this description as a 'low' could be a 'high' and a 'high' could be a 'low'. In some embodiments, the transition on the receiving pin, from 'low' to 'high' denotes a binary '<NUM>'. Diode <NUM> prevents the voltage into the power module <NUM> of second device <NUM> from dropping rapidly. A capacitor <NUM> positioned between the line connecting resistor <NUM> and power module <NUM>, and the ground, provides a small amount of power as the power supplied to device <NUM> through its power module <NUM> starts to drain the current from that node. The combination of diode <NUM> and capacitor <NUM> momentarily minimizes the voltage drop into the power supply from power module <NUM>.

Once a sufficient amount of time is given for second device <NUM> to have seen the input from wire <NUM> drop 'low', first device <NUM> turns first transistor <NUM> back to a non-conducting state, which turns transistors <NUM> to a conducting state, thereby allowing a normal amount of current to flow through wire <NUM>. If first transistor <NUM> is turned on to a conducting state and then back to a non-conducting state relatively quickly, second device <NUM> registers the change as data, but the power supplied to second device <NUM> remains constant. The amount of time in which transistor <NUM> changes its state from on to off may be determined on the basis of amount of current consumed by device(s) <NUM>, the leakage of current back through diode <NUM>, and the size of capacitor <NUM>.

For second device <NUM> to transmit a bit of data to first device <NUM>, transistor <NUM> and therefore transistor <NUM> are turned on to a conducting state by processor <NUM>. Input from wire <NUM> through a resistor <NUM>, positioned between output of wire <NUM> and transistor <NUM> of second device <NUM>, is momentarily pulled 'low'. A comparator <NUM> on first device <NUM> senses the power output through resistor <NUM> drops to 'low' and consequently changes a receiving pin on a processor <NUM> within first device <NUM> to 'high'. After a sufficient amount of time expires, processor <NUM> on second device <NUM> switches off conduction through transistor <NUM> and wire <NUM> input to second device <NUM> rapidly rises back up to the supply level since that input is no longer shorted to ground. Comparator <NUM> detects the output voltage transitioning back to 'high' and sets the receiving pin on processor <NUM> of first device <NUM> back to 'low'.

In embodiments, resistor <NUM> on first device <NUM> keeps the regulator of first device <NUM> (the supply) from overcurrent during the intermittent short circuit events seen on the power line during transmission by second device <NUM>. During these transmissions, transistors <NUM> and <NUM> are in a conducting state, so any momentary short circuit events of wire <NUM> are detected by power module <NUM> which puts system <NUM> into an overcurrent condition.

According to the invention, the communication over wire <NUM> is asynchronous, implying that a device (first device <NUM> or second device <NUM>) could initiate communication on wire <NUM> at any time. Therefore, it is important for each device <NUM> and <NUM> to be able to detect possible data collisions. A data collision may occur when both devices <NUM> and <NUM> are sending data at the same time. When a device wishes to transmit data, it enters into a transmit state. In that state it should only detect the receiving pin change state when it has changed the state of a device processor's transmitting pin. If the receiving pin changes when the transmitting pin has not changed, then the processor (<NUM>, <NUM>) concludes that it has sensed a collision and an upper level protocol of processors <NUM> and <NUM> of system <NUM> are signaled of such an event. It will be up to the upper level protocol to initiate any corrective action (according to the invention a backoff for some random amount of time followed by a retry).

<FIG> illustrates an exemplary circuit <NUM> where the systems in accordance with some embodiments of the present specification were simulated. In one embodiment, a left side of the circuit <NUM> relates to a device <NUM> corresponding to first device <NUM> described with reference to <FIG>. Similarly, a right side of circuit <NUM> relates to a device <NUM> corresponding to second device <NUM> of <FIG>. A wire <NUM> (<NUM>) connects devices <NUM> (<NUM>) and <NUM> (<NUM>). Components of <FIG> correspond to the various components of <FIG> and are numbered similarly. For example, transistors <NUM> and <NUM> correspond to the transistors <NUM> and <NUM> of first device <NUM>/<NUM>. In alternative embodiments, there can be multiple devices similar to device <NUM>, which may be connected to device <NUM> through wire <NUM>. In embodiments, the number of devices, similar to device <NUM>, which may be connected through wire <NUM> to device <NUM>, is limited by the power supplied by device <NUM> and consumed by multiple devices <NUM>. Additionally, the numbers of multiple device <NUM> is limited by the protocols' ability to address more than a specific number of devices individually. In one embodiment, up to eight devices <NUM> are connected to device <NUM>.

Referring again to <FIG>, a voltage supply simulation 'HostProc' which is connected to Vgate simulates the interaction with processor <NUM>. The remaining portions of processor <NUM> are not simulated. Similarly, a voltage supply simulation 'DevProc' simulates the interaction of the processor <NUM> and the remaining portions of that processor are not simulated. Referring to <FIG>, a resistance 'WIreR_1' <NUM> and capacitance 'WireC_1' <NUM> are used to simulate parasitic resistances and capacitances of the wire <NUM>. Finally, component U5 and associated components C9 through C13, in the power supply <NUM> of the first device <NUM>, are optional. In some embodiments voltage dividers and op-amps make up comparator portions <NUM> and <NUM>, respectively within devices <NUM> and <NUM>, of circuit <NUM>. However, there is no restriction to that portion of the circuit - other circuits such as those with internal references may also be used.

<FIG> illustrates transmission of data from first device <NUM>/<NUM> to second device <NUM>/<NUM>, shown in <FIG> and <FIG>, in accordance with some embodiments of the present specification. Simultaneous reference to components of <FIG> and <FIG> is made to enhance the description of the graphs. The figure shows transmission of a value of 0xFFFF (<NUM> sets of <NUM> bits of <NUM>'s). Lower graph <NUM> shows the input provided to the transmit transistor (transmitting pin of transistor <NUM> of <FIG>). Middle graph <NUM> shows comparator <NUM>/<NUM> op-amp inputs on second device <NUM>/<NUM> where a line <NUM> drawn across graph <NUM>, is the reference voltage. In an embodiment, the reference voltage is between <NUM>. 19V and <NUM>. Top graph <NUM> shows the output of comparator <NUM>/<NUM> which is for all practical purposes identical to the transmitted input. In an exemplary embodiment, these transmissions were simulated at a rate of <NUM>.

<FIG> illustrates transmission of data from second device <NUM>/<NUM> to first device <NUM>/<NUM> in response to the data transmission of <FIG>, in accordance with some embodiments of the present specification. In a first graph <NUM>, a top trace <NUM> shows the input supply rail to the regulator <NUM> of second device <NUM>/<NUM>. Some amount of expected sag is seen in trace <NUM>, which occurs as a result of the power input intermittently dropping out. The output of that supply, however, remains constant at <NUM>. 3V (as shown in a lower trace <NUM> of graph <NUM>) since the input is above the drop-out limit of the regulator. In some embodiments, regulators with low dropout values are selected to keep the slave device(s), such as second device <NUM>/<NUM>, from drawing the power down below into the dropout range of their regulator(s). Alternatively, in some embodiments, the power resistor, such as resistor <NUM>, is adjusted. A second graph <NUM> shows the current through resistor <NUM>. A graph <NUM> below graph <NUM> shows comparator <NUM> output of first device <NUM>/<NUM>, which is identical to the inputs from both of devices <NUM>/<NUM> and <NUM>/<NUM>. A fourth graph <NUM> shows op-amp inputs <NUM> of first device <NUM>/<NUM> with a straight line <NUM> being the reference input voltage. A graph <NUM> shows an output <NUM> of the comparator <NUM>. Traces <NUM> in a graph <NUM> show the signal and reference inputs, respectively, to the comparator <NUM>. A trace <NUM> in a lower graph <NUM> is the input to transistor <NUM> of second device <NUM>/<NUM>.

Additionally care needs to be taken to minimize the pulse widths of the bits transmitted and to allow enough recovery time in-between transmissions. Therefore, the pulse width of each bit is controlled. The bandwidth (baud rate) at which the transmission is driven may be a factor in controlling the pulse width for each bit. Independent of the baud rate, if the actual data transmission rate is low, a sag in the applied voltage is small. As the transmission rate increases and approaches the full bandwidth (baud rate) of the channel, the sag will worsen. In some embodiments, these signals are in the kHz range and the low portion of the pulse is minimized. In embodiments, pulse width depends upon the speed of each processor (<NUM> and <NUM>) and on the current draw of each <NUM> device. The size of capacitor <NUM>, the leakage of diode <NUM>, and the drop-out voltage value of regulator <NUM> may also affect the pulse width. Pulses of equal high and low widths that are between <NUM> and <NUM> are easily accommodated without resorting to larger or more expensive components.

<FIG> illustrate images of a first end <NUM> of a wire that connects the first master device <NUM> (<FIG>) and the second slave device <NUM> (<FIG>), in accordance with some embodiments of the present specification. The first end <NUM> is a plug portion of the wire that connects with a physiological monitoring system, such as device <NUM> shown in <FIG>. <FIG> illustrates a photograph of the plug portion <NUM>, in accordance with some embodiments of the present specification. <FIG> illustrates a line drawing of the plug portion <NUM>, including a cross-section view of its housing. <FIG> illustrates a line drawing of the plug portion <NUM> with dimensions of its components. Referring simultaneously to <FIG>, the plug portion comprises a pin <NUM> that is configured to be placed inside a corresponding female port of the physiological monitoring device, thereby providing an electrical connection between the wire and the physiological monitoring device. A pointed end of the pin <NUM>, extending for a length of approximately <NUM> millimeters (mm) and with a diameter of approximately <NUM>, emerges from a band of approximately <NUM> that joins the pointed end of the pin <NUM> to an opposite end of the pin <NUM>, which extends for a length of approximately <NUM> and has a diameter of approximately <NUM>. At the opposite end, the pin <NUM> is connected to a protective housing <NUM>. The housing <NUM> encompasses a switch with electrical components of the wire that provides communication of power and data from and to the physiological monitoring device when the pin is plugged into the physiological monitoring device. A total length of the plug portion <NUM> extends for approximately <NUM>. In embodiments, the pin portion <NUM> plugs into a special pin on the physiological monitoring device or is built into a yoke.

Claim 1:
A physiological lead wire configured to monitor a motion of a person and to monitor a physiological parameter of the person, comprising:
a connecting wire (<NUM>) having a first end and an opposing second end;
a connector plug (<NUM>) attached to the first end, wherein the connector plug is configured to electrically connect the physiological lead wire with a physiological monitoring system, wherein the physiological monitoring system is at least one of an electrocardiogram, ECG, monitoring device, a respiration monitoring device, a SpO<NUM> monitoring device, or a blood pressure monitoring device;
a receptacle at the second end, wherein the receptacle (<NUM>) is configured to attach to the person;
a motion detector (<NUM>) integrated into the receptacle, wherein the motion detector comprises a printed circuit board and a processor (<NUM>) comprising a transmit port and a receive port coupled to the connecting wire, and configured to acquire positional and movement information of the person and to transmit the positional and movement information over the connecting wire; and
a physiological sensor integrated into the receptacle, wherein the physiological sensor is configured to acquire physiological data of the person, the processor configured to transmit the physiological data over the connecting wire and wherein the physiological data comprises at least one of ECG data, respiration data, SpO<NUM> data, or blood pressure data;
wherein the processor is configured to communicate data asynchronously with the monitoring system across the connecting wire, and
wherein the processor is configured, responsive to detecting a data collision based on signals transmitted by the transmit port not matching signals received at the receive port, to halt transmission for a period of time.