CN210056040U - Separately powered continuous blood glucose monitoring transmitter and system - Google Patents

Abstract

The utility model discloses a separate power supply dynamic blood glucose monitoring transmitter and a system thereof. The structure comprises a transmitter and a sensor base device; the sensor base device is divided into a base and an adhesive tape. The base is provided with a battery slot and a groove, and a battery is installed in the battery slot. , a rotary seat is installed in the groove, one side of the rotary seat is hinged in the groove, the rotary seat has a silicone seat, a pair of conductive rubbers are arranged in the silicone seat, the transmitter includes a circuit board assembly, and the circuit board assembly has four A conductive needle can contact the positive and negative electrodes of the battery and two conductive rubbers. Compared with the prior art, the utility model can separate the button battery from the transmitter and integrate it with the sensor. When not in use, the transmitter has not been installed on the sensor base, so the transmitter is in a power-off state. , The button battery does not consume power. When in use, the transmitter is buckled on the sensor base, and the battery on the sensor base supplies power to the transmitter through electrical connection.

Description

Separately powered continuous blood glucose monitoring transmitter and system

technical field

The utility model relates to a separate power supply dynamic blood glucose monitoring transmitter and a system thereof, belonging to the technical field of wearable medical devices.

Background technique

The traditional continuous blood glucose transmitter is mainly composed of three parts, button battery, circuit board and plastic casing. Due to waterproof requirements and volume constraints, the button battery and the circuit board are generally placed in the transmitter together, and the two are usually plastic-molded together. Therefore, the transmitter battery cannot be replaced, and the one-time sensor is generally used for 3-14 days. , it will be discarded after use. When the battery life is used up, the transmitter is basically unusable. From the perspective of cost, the cost of the plastic casing and circuit board of the transmitter is much greater than the cost of the battery, and the life of the plastic casing and the circuit board of the transmitter is also much longer than that of the battery. Therefore, this method will greatly waste the circuit board and the plastic casing, increasing the material cost and waste.

The use of polymer rechargeable lithium batteries can improve the problem of cost waste, but the polymer battery will have the problem of loss. After considering the number of charging times, its lifespan is still much lower than the lifespan of circuit boards and plastic casings, which cannot fundamentally solve the above problems. In addition, there is no standard product suitable for transmitters for polymer rechargeable batteries, which usually requires non-standard supply from battery suppliers, which increases the difficulty of procurement.

In addition, in order to effectively utilize the life of the transmitter circuit board and the plastic case, the cost and waste are reduced. Usually, a button battery with a slightly larger volume (more power) is selected, which cannot make the transmitter smaller, which reduces the wearing experience.

In order to solve the above problems, a suitable way is adopted to separate the battery from the transmitter, so that the service life of the circuit board and the plastic case is not limited by the battery life. On the one hand, it is very meaningful to reduce costs and waste, and on the other hand On the one hand, a smaller battery can be used to reduce the system volume and improve the wearing experience.

In addition, the dynamic blood glucose transmitter calculates the blood glucose concentration by sampling the current value of the sensor, so the accuracy of the sampling sensor directly affects the accuracy of calculating the blood glucose concentration, and the wireless SOC module generally has a built-in ADC sampling circuit, and the accuracy of this circuit is usually marked with Called around 10 to 12 bits, the effective precision may be slightly lower than the nominal value. If higher accuracy is required, an expensive external ADC circuit needs to be added.

Utility model content

The technical problem to be solved by the present invention is to provide a high-precision dynamic blood glucose monitoring transmitter and a system thereof with separate power supply in view of the above-mentioned deficiencies of the prior art.

In order to solve the above-mentioned technical problems, the technical scheme adopted by the present utility model is:

A separate power supply dynamic blood glucose monitoring transmitter, comprising a transmitter and a sensor base device; the sensor base device includes a base and an adhesive tape, the base is located on the adhesive tape; the upper part of the base is an opening, and the base is provided with a battery slot and a groove, so A battery and a battery cover are installed in the battery slot, a rotating seat is installed in the groove, the rotating seat is hinged in the groove by one side of the battery slot, the rotating seat has a silica gel seat, and a pair of silica gel seats are arranged in the silica gel seat. Conductive rubber, a sensor is arranged through the silicone base and the rotating base, the sensor can pass through the two conductive rubbers, the groove has an opening on the side of the battery slot, the tape is provided with a hole, and the sensor can pass through the opening and the gap of the tape. The transmitter includes a plastic casing and a circuit board assembly, the plastic casing is covered on the base, the circuit board assembly is installed on the top of the plastic casing, and the circuit board assembly has four conductive pins, which can contact the battery Positive and negative electrodes and two conductive rubbers.

As a further preferred solution, the silicone seat is provided with a first conductive rubber hole and a second conductive rubber hole, and the two conductive rubbers are respectively installed in the first conductive rubber hole and the second conductive rubber hole; Two square holes are also provided, the two conductive rubbers and the two square holes are distributed in a straight line, and the sensor passes through the two conductive rubbers.

As a further preferred solution, a semi-circular hole is opened on both sides of the groove, and a flexible extension rod is provided on both sides of the end of the rotating seat, and the outer side of the extension rod has a cylindrical shaft, The cylindrical shaft is placed in the semicircular hole to rotate.

As a further preferred solution, an electrode adapter is installed on the positive and negative electrodes of the battery, each electrode adapter is provided with an electrode connector, and the battery cover is provided with two circular holes, one circular hole. The hole corresponds to an electrode connector, and the electrode connector passes through the circular hole and is placed outside the battery cover.

As a further preferred solution, the four conductive pins on the circuit board assembly are two battery guide pins and two rubber guide pins, the two battery guide pins are respectively connected to an electrode connector, and the two rubber guide pins are respectively connected to a Conductive rubber.

As a further preferred solution, the end of the base has a base snap opening, the end of the plastic-encapsulated shell has an edge boss inserted into the base snap opening; the side of the plastic-encapsulated shell has a shell slot, the The inner side wall of the groove is provided with elastic buckles that are clamped into the casing grooves.

As a further preferred solution, the edge of the battery slot is provided with a sealing strip, and the edge of the silicone seat is provided with a rib.

A system for separating and supplying dynamic blood glucose monitoring transmitters, including an LC filter energy storage module, a wireless SOC module, a functional circuit power module, a sensor excitation and conditioning module, an ADC precision enhancement module, a battery and a sensor, the positive and negative electrodes of the battery pass through respectively. The line is connected to the LC filter energy storage module, and there is a connection line between the LC filter energy storage module and the VDD end of the wireless SOC module. The connection line has a double control switch, and the double control switch can be connected to the Da end of the wireless SOC module or the functional circuit power supply The module, the functional circuit power supply module is connected to the sensor excitation and conditioning module, and the Db end of the wireless SOC module is also connected to the sensor excitation and conditioning module. The wireless SOC module has a built-in ADC module, and the Dc end of the wireless SOC module and the built-in ADC module are both Connect the ADC precision enhancement module, the ADC precision enhancement module line is connected to the sensor excitation and conditioning module, and the positive and negative poles of the sensor excitation and conditioning module are respectively connected to the sensor.

Compared with the prior art, the beneficial effect of the present invention is that the button battery is separated from the transmitter and integrated with the sensor. When not in use, the transmitter is not yet mounted on the sensor base, so the transmitter is powered off and the coin cell battery is not draining. When in use, the transmitter snaps into the sensor base, and a battery on the sensor base powers the transmitter through an electrical connection. When finished, remove the transmitter and discard the coin cell battery along with the sensor. In this way, the coin cell battery only needs to support the power of the sensor for one cycle. On the one hand, the volume of the button battery will be reduced, and on the other hand, the cost of the battery will be reduced. In addition, since the transmitter can be reused, the cost will also be greatly reduced.

The newly designed ADC accuracy enhancement circuit can enhance the sampling accuracy by 1 bit; the LC filter energy storage circuit can reduce the battery capacity (volume) on the one hand, and make the transmitter power supply more stable on the other hand; and the wireless SOC module power supply The power supply is separated from the power supply of the functional circuit, which effectively reduces the power consumption. And a soft power-on method is designed to make the transmitter work more stable and reliable.

Description of drawings

Fig. 1 is the structural representation of the utility model;

Figure 2 is an exploded view of the launcher;

Figure 3 is an exploded view of the sensor base device;

Figure 4 is a cross-sectional view of a silicone seat;

Fig. 5 is the structural representation of the base;

6 is a schematic diagram of the structure of the battery cover;

FIG. 7 is a schematic structural diagram of a rotating seat and a silicone seat;

8 is a schematic diagram of a system module of the present invention;

9 is a schematic circuit diagram of a functional circuit module;

Figure 10 is a schematic diagram of soft power-on of the functional circuit power supply;

Figure 11 is the sensor excitation and conditioning module circuit;

Figure 12 is the ADC precision enhancement module circuit;

Figure 13 is an LC filter energy storage module circuit;

Figure 14 is a wireless SOC module circuit.

Detailed ways

The preferred technical solutions of the present utility model will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 1 , the transmitter system is structurally divided into two parts: the transmitter 200 and the sensor base device 300 . The sensor electrodes 301 connected to the sensor base device 300 can be implanted into the recipient tissue through an auxiliary implant device. For the auxiliary implantation device, please refer to the published patent CN206424078U.

As shown in FIG. 2 , the hardware of the transmitter 200 includes a circuit board assembly 201 and a plastic package 202 . The size of the transmitter is about 32mm*16mm*5mm. After being installed in the sensor base device 300, it is convenient to stick to the skin of the receptor and carry it with you.

The circuit board assembly 201 includes four conductive pins, and the conductive pins are generally made of conductive metal, preferably brass. The conductive pins are drawn out from the plastic casing 202 and are flush with the bottom surface of the plastic casing. After the transmitter 200 is snapped into the sensor base device 300, the conductive pins are respectively connected to the sensors S+, S- and the battery V+V-. The battery 304 in the sensor base 300 will supply power to the transmitter 200, and the transmitter 200 can convert the signal values measured from the sensor 301 into corresponding physiological parameters and send them to the user receiving end.

The plastic-encapsulated casing 202 completely wraps the circuit board assembly (except the four conductive pins), which can achieve waterproofing. There is an edge boss 2021 on the left side of the plastic package, and a shell slot 2022 on each side. When the transmitter is installed on the sensor base, the edge boss 2021 and the shell slot 2022 can fix the transmitter 200 on the base.

As shown in FIG. 3 , the sensor base device 300 mainly includes a battery 304 and a sensor 301 . Wherein the battery 304 and the transmitter 200 are connected by electrical contacts V+ and V-. Sensor 301 and transmitter 200 are connected by electrical contacts S+S-.

The sensor base device 300 includes a sensor 301, a base 302, a tape 303, a battery 304, a battery adapter 305, an electrode connector 306, a battery cover 307, a waterproof sealing ring 308 for the battery connector, a rotating seat 309, a silicone seat 310, a conductive Rubber et al. 311.

The battery adapter 305 may be a metal part such as a nickel strip. The battery adapter 305 is connected to the battery 304 and the battery connector 306 by welding or the like.

For the battery 304, insulating paper is provided outside the battery to prevent the positive and negative electrodes of the battery from conducting.

The battery connector 306 is placed on the battery adapter 305 and can be pressed by the installation of the battery cover 307 .

The battery connector 306 is resilient and enables a resilient electrical connection to the transmitter. Preferably, the battery connector 306 can be a spring pin with a spring inside. When the transmitter 200 is installed, the contacts of the battery connector are pressed down to ensure reliable contact between the battery connector contacts and the transmitter contacts.

The base 302 has a waterproof sealing ring 308 on the surface, and the waterproof sealing ring can be elastic materials such as silicone, TPE, TPU, etc. The waterproof sealing ring can be directly injected on the base, or it can be bonded to the base later. The waterproof sealing ring is trapezoidal or triangular, which can better place the transmitter and can be better waterproof. When combined with the bottom plane of the transmitter, it can play a waterproof role, and the waterproof level can reach IPX7.

When not in use, the transmitter 200 is not installed on the sensor base device 300, so the transmitter 200 is in a power-off state and the battery 304 is not consumed. When in use, the transmitter 200 snaps onto the sensor base assembly 300, and the battery on the sensor base assembly 300 powers the transmitter 200 through an electrical connection. When finished, the transmitter is removed and the battery 304 is discarded with the sensor.

As shown in FIG. 4, the sensor 301 is implanted in the subcutaneous tissue of the living body for sensing the raw signal of the analyte. The sensor 301 includes at least one working electrode and one reference electrode. The working electrode and the reference electrode S+S- are electrically connected through the conductive rubber 311 and the battery guide pins 2011 and 2012 of the transmitter 200, respectively.

The base 302 is, on the one hand, fixed on the recipient's skin by a non-woven tape 303, and on the other hand is used to fix and connect the transmitter 200.

As shown in FIG. 5 , the base 302 has a battery slot 3021 with a diameter of 12 mm in the middle for placing the battery 304 . The positive and negative electrodes of the battery are connected to the battery connector 306 through the battery adapter 305, and then lead to the outer surface of the base through the battery connector.

The base 302 is provided with a base snap opening 3023 at the end. The top of the opening is flat, and the bottom is provided with an angled slope. The top surface is used to cooperate with the edge boss 2021 of the transmitter 200 to limit the transmitter. Bottom bevel facilitates transmitter installation.

The base 302 has a groove 3024 on the right side, and the groove is used for placing the rotating seat 309 . After the sensor 301 is implanted, the rotating seat rotates clockwise by a certain angle, and finally fits with the bottom surface of the groove. The lower left side of the groove 3024 has an opening 3025 through which the sensor 301 can pass.

A semi-circular hole 3026 is provided on both sides of the groove 3024, and the semi-circular hole is matched with the cylindrical shaft 3092 of the rotating seat 309, so that the rotating seat can rotate along the axis of the hole.

An inclined surface is provided above the semicircular hole 3026, and the inclined surface is used to facilitate the clamping of the cylindrical shaft of the rotating seat into the semicircular hole.

Both sides of the base 302 are provided with elastic buckles 3027. The elastic buckles are used to cooperate with the casing slots 2022 on both sides of the transmitter. When the transmitter is installed, the elastic buckles on both sides of the base are opened outwards. When in place, the elastic snaps retract. The bottom surface of the elastic buckle is locked with the slot of the launcher, which restricts the movement of the launcher.

As shown in FIG. 6 , the battery cover 307 is used to cooperate with the base 302 to fix the battery connector 306 and the battery 304 . A battery cover groove 3071 is provided in the middle of the battery cover 307 for accommodating the battery 304 . Both ends have a cylindrical hole step surface 3072, and the battery connector is fixed by cooperating with the two cylindrical steps 3022 corresponding to the bottom surface of the base. The two round holes 3073 on the top of the battery cover 307 allow the elastic parts of the battery connector to pass through, so as to be in contact with the transmitter contacts.

As shown in FIG. 7 , the rotating seat 309, on the one hand, provides support for the silicone seat 310 on it when it is not installed; on the other hand, when the installation is completed, it can rotate around the base to the installed state.

There are two extension rods 3091 on both sides of the rotating seat 309. The extension rods have a certain elasticity. When the extension rod is subjected to force, it can be retracted inward; after the force is removed, the extension rod can return to its original position.

Each end of the rod has a cylindrical shaft 3092, which is matched with the semicircular hole of the base.

The cylindrical shaft 3092 has an inclined surface on the side. When the rotating seat is installed in the base, the inclined surface of the cylindrical shaft contacts and guides the inclined surface of the base. Under the action of the pressing force, the extension rod 3091 shrinks inwardly, the cylindrical shaft is clamped into the semicircular hole of the base, and the extension rod can return to its original position. At this time, the degrees of freedom of the rotating seat and the base are limited, and the rotating seat can only rotate around the cylinder axis.

The silicone seat 310, on the one hand, is used to store the conductive rubber 311, provide deformation space for the conductive rubber and limit the conductive rubber; .

The silicone seat 310 has a first conductive rubber hole 3101 and a second conductive rubber hole 3102 in the middle. The circular hole is used to place the conductive rubber 311 .

There are two conductive rubbers 311. After the implantation is completed, the sensor 301 passes through the conductive rubber. Resilient electrical connection between transmitters. In addition to the electrical connection, the conductive rubber maintains the position of the sensor through friction under pressure.

The silicone seat 310 also has two square holes 3103 . The purpose of the square hole is to reduce the resistance when the guide needle and the puncture needle are withdrawn from the silicone seat.

The silicone seat 310 has a circle of trapezoidal or triangular ribs 3104 on the top, which can make the installation of the transmitter lighter and better waterproof.

Before use, the rotating base 309 and the base 302 are arranged at 45°, and the hollow guide needle in the implanter passes through the rotating base 309 and the silicone base 310 in parallel, and passes through the first conductive rubber hole 3101 and the second conductive rubber hole 3102; The hollow puncture needle is located in the guide needle, and the needle tip is used to puncture the skin of the recipient. The sensor 301 is a solid needle body made of soft material, and is located in the puncture needle. During use, through the driving force of the implanter, the puncture needle enters the human body with the sensor 301, and then the puncture needle and guide needle can be pulled out to keep the sensor 301 in the human body, and finally the implanter is disassembled, and the transmitter 200 is installed in the body. on the base 302. At this time, the battery on the base supplies power to the transmitter through the battery guide pin 2011 connected to V+V-. The rubber guide pin 2012 connected with the transmitter S+S-, the conductive rubber 311 and the sensor 301 form an electrical circuit. When the glucose oxidase on the sensor reacts with glucose inside the receptor, a weak current is generated. The transmitter can measure the current value through the above electrical circuit. And through the internal algorithm of the transmitter, the measured current value is converted into the blood sugar value of the receptor. Then through the wireless transmission module, the blood glucose value is transmitted to the corresponding display device.

As shown in Figure 8, in the SOC module, VDD is the power supply voltage of the SOC, and Da, Db, and Dc are the digital output pins of the SoC module. The Da pin is used to control the opening and closing of switch S1, so as to control whether the battery supplies power to the functional circuit power module. Db is used to select the level of the sensor excitation circuit, so that the sensor excitation module can provide the sensor with two excitation voltage signals of high level and low level. Dc is used to inject a noise signal into the ADC precision enhancement block. Ain1 and Ain2 are ADC inputs for sampling the conditioned and noise injected sensor voltage output from the ADC precision enhancement module.

As shown in FIG. 9 , Q2 (corresponding to switch S1 of FIG. 1 ) implements the module function of switch S1 . Its gate pole VPER_SHDN (corresponding to the Da signal in Figure 1) is connected to Pin37 of the Bluetooth master control chip U0 in the wireless SOC module circuit.

When VPER_SHDN is low, VBAT and V_PER are turned on. The battery starts to supply power to the functional circuits including the sensor excitation and conditioning module circuit and the ADC precision enhancement module circuit.

When VPER_SHDN is high, VBAT and V_PER are disconnected, and the functional circuits including sensor excitation and conditioning module circuit and ADC precision enhancement module circuit do not work, which can save power consumption. The L1 and L2 inductors mainly divide the digital circuit and the analog circuit. Since the analog circuit signal is a small signal sampling, the division of the digital and analog circuit can ensure that the analog signal is cleaner. U1 is a precision reference power supply with an accuracy of one thousandth. The input is an analog power supply VCCA, and the output is a reference voltage signal VS_REF, which is used as a reference level for applying sensor excitation. C1 and C2 are power filter capacitors.

The utility model adopts the soft power-on of the functional circuit power supply. When the functional circuit needs to be powered on, the wireless SOC module applies a PWM chopping waveform with a timing length of t to the gate of Q2, as shown in Figure 10, the PWM duty cycle gradually increases At this time, the output voltage of the analog switch rises slowly, and its current will maintain a small value range during the voltage rise. The magnitude of the current is related to the PWM period and duty cycle. The size of the power-on current using the PWM soft power-on method can be adjusted according to the PWM duration, duty cycle and PWM period, so this method is used. If you do not use soft power-on, but directly use a high-leveling and hard-on method for the gate of Q2, because there are a large number of filter capacitors in the functional circuit, the instantaneous charging current (also in the form of pulse current) is often very large at this time. It may be that the capacity in the LC filter capacitor is not enough, which will cause the battery voltage to drop, causing the system to reset due to power failure.

As shown in Figure 11, R1, R2, R3, R4, R5, R6, Q1, U5 constitute the sensor excitation circuit, and the gate of Q1 is connected to Pin39 of the Bluetooth master chip U0 in the wireless soc module. The output VS+ of the sensor excitation circuit is connected to the positive electrode of the sensor through the electrical contact S+ of the transmitter. VS_REF is the precision reference voltage source output in the functional circuit power supply module. The calculation relationship between the output VS+ and VS_REF is as follows,

When VS_SEL (corresponding to the Db signal in Figure 1) is high:

Among them, R4//R5 represents the equivalent resistance value of R4 and R5 in parallel

When VS_SEL (corresponding to the Db signal in Figure 1) is low:

R7, R8, C5, and U6 form a conditioning circuit, which is essentially an I-V operation circuit. Its main function is to convert the current signal flowing into VS- into a voltage signal ADC_GLU for the ADC module to convert into a digital signal. Pin3 of U6 is connected to the negative electrode of the sensor through the electrical contact S- of the transmitter. According to the analysis method of the operational amplifier, it can be known that the voltage of S- should be equal to VS_REF. C3 and C39 are U5 and U6 power supply decoupling capacitors. C8 is a filter capacitor, which controls the noise bandwidth of the circulating current signal.

Assuming that the sensor current flowing into S- is I ₀ , the relationship between ADC_GLU and input I ₀ is:

ADC_GLU=VS_REF+I ₀ *R ₈

Since the sampled current is at the microamp level, R8 is preferably 1MΩ.

Generally, the precision of the built-in analog-to-digital conversion circuit ADC of the main control chip is fixed and limited, and sometimes it cannot meet the application requirements. The usual solution is to use an external ADC chip, but the off-chip ADC is usually more expensive. To this end, this example uses an ADC precision enhancement circuit module. The ADC precision enhancement circuit adopts the noise injection method, and the sampling precision can be enhanced by 1 bit on the basis of the fixed precision of the built-in ADC of the main control chip of the wireless SOC module. The sampling method is as follows: Step 1, inject a noise voltage with an amplitude of 0 into the sampling signal, perform ADC sampling, and the result is Read1; Step 2, inject a noise voltage with an amplitude of 0 into the sampling signal. The noise voltage (V _{ADC_REF} is the ADC reference voltage, d is the target precision number of digits), the ADC sampling is performed, and the result is Read2; in the third step, the final result Read=(Read1+Read2)/2, the obtained result accuracy can be enhanced by 1 bit.

As shown in Figure 12, injecting two levels of noise signals on the sampled signal for sampling separately, and averaging after sampling, the accuracy can be increased by 1-bit resolution.

The circuit for injecting the noise signal is realized by an addition operation circuit, and each sampling needs an addition operation circuit. As shown in the figure, U8, R13, R14, R15, R16 form a precision enhancement circuit for VS_REF. U9, R17, R18, R19, R20 form a precision enhancement circuit for ADC_GLU. The structure of each ADC precision enhancement circuit is the same. The precision enhancement circuit is filtered by the post-stage filter circuit composed of R9R10C8C9C10 and then outputs ADC_R and ADC_G, which are connected to the built-in ADC pins Pin41 and Pin42 of the Bluetooth master chip U0 in the wireless SOC module for analog-to-digital conversion. Bit11 (corresponding to the Dc signal in Figure 1) is the noise injection signal, which is connected to Pin38 of U0. The injected signal is only 3V at high level or 0V at low level.

Taking the VS_REF road as an example, let R ₁₃ =k*R ₁₄ and R ₁₉ =k*R ₂₀ , so where k= ^2d . When the actual ADC precision is 10 bits and the target precision is 11 bits, k should take a value close to 2048.

Step1: Bit11 outputs low level, V _Bit11 = 0, ADC sampling is performed, and the result is Read1;

Step2: Bit11 outputs high level, V _Bit11 = 3, ADC sampling is performed, and the result is Read2;

·Step3: The final result Read=(Read1+Read2)/2, which is the result after the enhanced precision.

设结果寄存器为12位寄存器，结果高位对齐于结果寄存器。表1表2给出信号注入后，精度增强的计算过程。In this example, the ADC standard conversion accuracy of the Bluetooth master chip when oversampling does not occur is 10 bits, and the reference voltage is calculated as 1 (100%), and its accuracy is

Let the result register be a 12-bit register, and the high-order bits of the result are aligned with the result register. Table 1 and Table 2 show the calculation process of precision enhancement after signal injection.

Table 1. 10-bit ADC and 11-bit ADC encoding table

Table 2. ADC Accuracy Enhanced Signal Calculation Example Table

From Table 2, it can be seen that by injecting (superimposing) a noise signal on the sampled voltage signal according to the method, summing the sampling results of each injected noise signal, and then averaging, the obtained result can increase the sampling accuracy by 1 bit.

As shown in Figure 13, the LC filter energy storage circuit can choose a button battery with a smaller capacity (volume), which can effectively reduce the impact of the pulse current of the wireless SOC module on the battery voltage when a radio frequency event occurs, and make the transmitter power supply more stable. Correspondingly, a battery with a smaller capacity (volume) can be selected to effectively reduce the impact of the pulse current of the wireless SOC module on the battery voltage when a radio frequency event occurs, so that the power supply of the transmitter is more stable. Correspondingly, a battery with a smaller capacity (volume) can be selected. Battery;

In the LC filter energy storage circuit, V+V- is connected to the positive and negative poles of the battery, and VDD_NRF supplies power to the Bluetooth main control chip in the wireless SOC module.

L6, C34, C35, C36, C37 constitute the LC filter tank circuit. Since the discharge capacity of the battery is related to the capacity, the pulse discharge capacity of conventional, general small-capacity CR series button batteries is about 5mA, while the current load of the Bluetooth chip is as high as 12mA or more when a radio frequency event occurs (when sending or receiving data wirelessly). , far exceeding the battery pulse discharge capacity.

When the battery pulse discharge capacity is insufficient, the voltage across the battery will be pulled down. When the voltage is too low, the Bluetooth main control chip will be reset, and the entire system will fail due to power failure. On the other hand, repeated pulse current will also cause damage to the battery itself, that is, the pulse current will make the actual operating capacity of the battery much smaller than the nominal capacity.

Considering that the RF event is intermittent, an inductor-capacitor filter energy storage circuit is added in this example. When there is no pulse current, C34, C35, C36, and C37 are mainly used for energy storage. When there is no RF time, the power consumption of the entire circuit is very small, so the battery charges the capacitor more than the capacitor discharges the system circuit, and the excess energy is stored in the capacitor. When a radio frequency event occurs, the pulse current required by the system circuit is preferentially obtained from the capacitor, so the battery does not need to provide pulse current, so that the battery is in a relatively gentle discharge state throughout the working cycle, effectively suppressing voltage sag events, and Prevent damage to the battery from pulsed current.

The inductor L6 mainly suppresses the current amplitude of the battery charging the capacitor. Because the pulse current is a high-frequency characteristic current, the inductor L6 can present a large impedance characteristic to high frequencies. When a pulse current occurs, L6 can make the battery discharge priority over the battery discharge, that is, the power stored in the capacitor is preferentially used.

As shown in FIG. 14 , for the wireless SOC module circuit, in this example, the Bluetooth chip U0 is preferred as the main control chip.

The power supply of the wireless SOC module and the power supply of the functional circuit are separated, and they supply power independently. The functional circuit power supply is mainly for the sensor excitation and conditioning circuit, and the precision enhancement circuit. The method of separate power supply is adopted, according to the principle of who works and who supplies power. When the functional circuit does not need to work, the battery power can be not consumed, and the power consumption can be effectively reduced. In order to power on the functional circuit reliably, a soft power-on method is designed, which effectively suppresses the pulse current amplitude at the moment of power-on and makes the transmitter work more reliable.

Capacitors C27, C28 and crystal Y1 provide a high-frequency clock source for the Bluetooth chip, and crystal Y1 is preferably 16MHz. Capacitors C21, C22 and crystal Y2 provide a low-frequency clock source for the Bluetooth chip, and crystal Y2 is preferably 32.768kHz.

DV, DIO, DCK, DG are emulation ports for emulation and programming. C23, C24, C25, C26, C29, C30, C33 are the power decoupling capacitors for the Bluetooth chip. L4, C31 and antenna ANT1 constitute a Bluetooth radio frequency circuit for modulating wireless signals.

Pin37 of U0 is connected to the gate of the switch S1 circuit Q2, which is used to control the on-off of the power supply of the functional circuit. When the functional circuit is not required to work, it outputs a low level, and the functional circuit is in a non-working state at this time, so as to achieve the purpose of saving power consumption.

Pin41 and Pin42 of U0 are the sensor current sampling signals passed through the ADC precision enhancement module circuit, which are used to calculate the blood sugar concentration.

Pin6 of U0 is connected to the positive electrode of the battery, and the voltage value of the battery is collected, which is used to calculate the power of the battery according to the voltage-power curve of the battery.

Pin39 of U0 is connected to the gate of Q1 in the sensor excitation and conditioning module circuit, which is used to select the level of excitation applied by the sensor. In this example, a mosfet can be used to apply two-level excitation to the sensor.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention In the utility model, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims (8)

1. Separation power supply developments blood sugar monitoring transmitter, its characterized in that: comprises an emitter (200) and a sensor base device (300); the sensor base device (300) comprises a base (302) and an adhesive tape (303), wherein the base (302) is positioned on the adhesive tape (303); the upper portion of the base (302) is provided with an opening, a battery jar (3021) and a groove (3024) are arranged in the base (302), a battery (304) and a battery cover (307) are installed in the battery jar (3021), a rotating base (309) is installed in the groove (3024), one side, close to the battery jar (3021), of the rotating base (309) is hinged in the groove (3024), a silica gel base (310) is arranged in the rotating base (309), a pair of conductive rubbers (311) are arranged in the silica gel base (310), a sensor (301) is arranged to penetrate through the silica gel base (310) and the rotating base (309), the sensor (301) can penetrate through the two conductive rubbers (311), one side, close to the battery jar (3021), of the groove (3024) is provided with an opening (3025), the adhesive (303) is provided with a hole, and the sensor (301) can penetrate through the openings (3025) and the adhesive (303); the transmitter (200) comprises a plastic package shell (202) and a circuit board assembly (201), wherein the plastic package shell (202) is covered on the base (302), the circuit board assembly (201) is installed inside the plastic package shell (202), four conductive pins are arranged on the circuit board assembly (201), and the conductive pins can contact the positive electrode and the negative electrode of the battery (304) and two conductive rubbers (311).

2. The separately powered ambulatory blood glucose monitoring transmitter of claim 1, further comprising: the silicon rubber base (310) is provided with a first conductive rubber hole (3101) and a second conductive rubber hole (3102), and the two conductive rubbers (311) are respectively arranged in the first conductive rubber hole (3101) and the second conductive rubber hole (3102); two square holes (3103) are further arranged in the silicon rubber seat (310), two conductive rubbers (311) and the two square holes (3103) are linearly distributed, and the sensor (301) penetrates through the two conductive rubbers (311).

3. The separately powered ambulatory blood glucose monitoring transmitter of claim 1, further comprising: two sides in the groove (3024) are respectively provided with a semicircular hole (3026), two sides of the end part of the rotating base (309) are respectively provided with a flexible extension bar (3091), the outer side of the extension bar (3091) is provided with a cylindrical shaft (3092), and the cylindrical shaft (3092) is arranged in the semicircular hole (3026) to rotate.

4. The separately powered ambulatory blood glucose monitoring transmitter of claim 1, further comprising: the battery comprises a battery body (304), wherein the positive electrode and the negative electrode of the battery body (304) are respectively provided with an electrode adapter (305), each electrode adapter (305) is provided with an electrode connecting piece (306), the battery cover (307) is provided with two round holes (3073), one round hole (3073) corresponds to one electrode connecting piece (306), and the electrode connecting piece (306) penetrates through the round holes (3073) and is partially arranged outside the battery cover (307).

5. The separately powered ambulatory blood glucose monitoring transmitter of claim 4, wherein: four conductive pins on wiring board subassembly (201) are two battery guide pins (2011) and two rubber guide pins (2012), and an electrode connecting piece (306) is connected respectively to two battery guide pins (2011), and a conductive rubber (311) is connected respectively to two rubber guide pins (2012).

6. The separately powered ambulatory blood glucose monitoring transmitter of claim 1, further comprising: the end part of the base (302) is provided with a base buckle opening (3023), and the end part of the plastic package shell (202) is provided with an edge boss (2021) inserted into the base buckle opening (3023); the side of the plastic package shell (202) is provided with a shell clamping groove (2022), and the inner side wall of the groove (3024) is provided with an elastic buckle (3027) clamped into the shell clamping groove (2022).

7. The separately powered ambulatory blood glucose monitoring transmitter of claim 1, further comprising: the battery jar (3021) is provided with a sealing strip (308) on one circle of the edge, and the silica gel base (310) is provided with a rib position (3104) on one circle of the edge.

8. A system of separately powered ambulatory blood glucose monitoring transmitters according to any of claims 1-7 and comprising: comprises an LC filtering energy storage module, a wireless SOC module, a functional circuit power supply module, a sensor excitation and conditioning module, an ADC precision enhancing module, a battery and a sensor, the positive pole and the negative pole of the battery are respectively connected with the LC filtering energy storage module through a circuit, a connecting line is arranged between the LC filtering energy storage module and the VDD end of the wireless SOC module, the connecting wire is provided with a double control switch which can be connected with the Da end of the wireless SOC module or the functional circuit power module, the functional circuit power module is connected with the sensor excitation and conditioning module through a circuit, the Db end of the wireless SOC module is also connected with the sensor excitation and conditioning module through a line, the wireless SOC module is provided with a built-in ADC module, the Dc end of the wireless SOC module and the built-in ADC module are both connected with the ADC precision enhancing module, the ADC precision enhancing module is connected with the sensor excitation and conditioning module through a line, and the positive electrode and the negative electrode of the sensor excitation and conditioning module are respectively connected with the sensor through a line.

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