CN111273368B - Geomagnetic sensor circuit, circuit board and electronic equipment - Google Patents

Abstract

The embodiment of the application provides a geomagnetic sensor circuit, a circuit board and electronic equipment, wherein the geomagnetic sensor circuit comprises a first magnetic sensor, a second magnetic sensor, an amplifier, an analog-to-digital converter and an interface unit; the first magnetic sensor is used for acquiring a first magnetic signal; the second magnetic sensor is used for acquiring a second magnetic signal, and the range of the magnetic signal acquired by the second magnetic sensor is larger than that of the magnetic signal acquired by the first magnetic sensor; the first magnetic sensor and the second magnetic sensor are both connected with the input end of the amplifier, and the amplifier is used for amplifying signals input into the amplifier; the analog-to-digital converter is used for acquiring the signal amplified by the amplifier and converting the amplified signal into a digital signal; the interface unit is used for acquiring the digital signal converted by the analog-to-digital converter and transmitting the digital signal. The method can support the measurement of small-range high precision and the measurement of large-range.

Description

Geomagnetic sensor circuit, circuit board and electronic equipment

technical field

The present application relates to the field of electronic technology, in particular to a geomagnetic sensor circuit, a circuit board and electronic equipment.

Background technique

Geomagnetic sensors are more and more widely used in electronic equipment. According to the geomagnetic sensor, the earth's magnetic field can be detected and the function of indicating the direction can be realized. In electronic devices such as smartphones, the application of geomagnetic sensors is very rich.

Contents of the invention

Embodiments of the present application provide a geomagnetic sensor circuit, a circuit board, and electronic equipment, which can increase the measuring range of the geomagnetic sensor circuit.

The embodiment of the present application also provides a geomagnetic sensor circuit, which includes:

a first magnetic sensor, configured to acquire a first magnetic signal;

The second magnetic sensor is used to obtain a second magnetic signal, and the range of the magnetic signal obtained by the second magnetic sensor is larger than the range of the magnetic signal obtained by the first magnetic sensor;

An amplifier, the first magnetic sensor and the second magnetic sensor are both connected to the input of the amplifier, and the amplifier is used to amplify the signal input to the amplifier;

An analog-to-digital converter, the input of the analog-to-digital converter is connected to the output of the amplifier, and the analog-to-digital converter is used to obtain the amplified signal of the amplifier and convert the amplified signal into a digital signal; and

The interface unit is connected to the output end of the analog-to-digital converter, and the interface unit is used to obtain the digital signal converted by the analog-to-digital converter and transmit the digital signal.

The embodiment of the present application also provides a circuit board, which includes:

Substrate;

A geomagnetic sensor circuit is arranged on the substrate, and the geomagnetic sensor circuit is the above-mentioned geomagnetic sensor circuit.

The embodiment of the present application also provides an electronic device, which includes:

case;

A circuit board is installed in the housing, and the circuit board is the above-mentioned circuit board.

In the embodiment of the present application, the first magnetic sensor can be used to measure a small-range magnetic signal, and the second magnetic sensor can be used to measure a large-range magnetic signal. The geomagnetic sensor circuit in the embodiment of the present application can support both small-range and high-precision It can also support large-scale measurement, and can be applied to more scenarios. At the same time, the magnetic signals obtained by the first magnetic sensor and the second magnetic sensor can be amplified through the amplifier, so that subsequent modules can obtain more accurate data.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings that need to be used in the description of the embodiments.

FIG. 1 is a schematic diagram of a first structure of a geomagnetic sensor circuit provided in an embodiment of the present application.

FIG. 2 is a schematic diagram of a second structure of a geomagnetic sensor circuit provided in an embodiment of the present application.

FIG. 3 is a schematic diagram of a third structure of a geomagnetic sensor circuit provided in an embodiment of the present application.

FIG. 4 is a schematic diagram of a fourth structure of a geomagnetic sensor circuit provided in an embodiment of the present application.

FIG. 5 is a schematic circuit diagram of a geomagnetic sensor circuit provided in an embodiment of the present application.

FIG. 6 is a schematic structural diagram of a circuit board provided by an embodiment of the present application.

FIG. 7 is a schematic structural diagram of an electronic device provided by an embodiment of the present application.

FIG. 8 is a schematic diagram of another side of the electronic device shown in FIG. 7 .

detailed description

The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Apparently, the described embodiments are only some of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the protection scope of this application.

Embodiments of the present application provide a geomagnetic sensor circuit, a circuit board, and electronic equipment. The geomagnetic sensor circuit is described in detail below.

Please refer to FIG. 1 . FIG. 1 is a schematic diagram of a first structure of a geomagnetic sensor circuit provided in an embodiment of the present application. The geomagnetic sensor circuit 100 includes a first magnetic sensor 122 , a second magnetic sensor 124 , an amplifier 140 , an analog-to-digital converter 160 and an interface unit 180 .

The first magnetic sensor 122 is used to obtain a first magnetic signal, and the second magnetic sensor 124 is used to obtain a second magnetic signal. The range of the magnetic signal obtained by the second magnetic sensor 124 is larger than the range of the magnetic signal obtained by the first magnetic sensor 122 .

The amplifier 140 can be a buffer amplifier or a preamplifier. Both the first magnetic sensor 122 and the second magnetic sensor 124 are connected to the input end of the amplifier 140 . The amplifier 140 is used to amplify the signal input to the amplifier 140 . For example, the first magnetic signal and/or the second magnetic signal may be amplified. The amplifier (Pre Amplifier) 140 may be an amplifier with a fixed multiple, such as 71 times. The amplifier 140 can also be an adjustable magnification amplifier, which can amplify different signals input to the amplifier 140 with different magnifications as required. Exemplarily, the adjustable magnifier can be adjusted between 0 times and 100 times.

An input terminal of an analog-to-digital converter (A/D Converter) 160 is connected to an output terminal of the amplifier 140, and the analog-to-digital converter 160 is used to obtain the amplified signal of the amplifier 140 and convert the amplified signal into a digital signal.

The interface unit 180 is connected to the output end of the analog-to-digital converter 160 , and the interface unit 180 is used to acquire the digital signal converted by the analog-to-digital converter 160 and transmit the digital signal.

The first magnetic sensor 122 can be used to measure a small-range magnetic signal, and the second magnetic sensor 124 can be used to measure a large-range magnetic signal. The geomagnetic sensor circuit 100 can support both small-range and high-precision measurement and a large-range. The measurement can be applied to more scenarios, and at the same time, the magnetic signals obtained by the first magnetic sensor 122 and the second magnetic sensor 124 can be amplified by the amplifier 140, so that subsequent modules can obtain more accurate data.

Please refer to FIG. 2 . FIG. 2 is a schematic diagram of a second structure of a geomagnetic sensor circuit provided in an embodiment of the present application. The geomagnetic sensor circuit 100 further includes a temperature sensor 132 (Temperature Sensor), which is used to acquire temperature information of the geomagnetic sensor circuit 100 , and the temperature sensor 132 is connected to the interface unit 180 . The interface unit 180 can be used to acquire temperature information of the temperature sensor 132, correlate the temperature information with a digital signal, and then transmit it. In some other embodiments, the interface unit 180 can also be used to acquire temperature information of the temperature sensor 132, adjust the digital signal according to the temperature information, and transmit the adjusted digital signal.

The temperature information collected by the temperature sensor 132 can be used to correct the results of the geomagnetic sensor circuit 100 . Magnetic signals obtained at different temperatures undergo different corrections. For example, when the temperature information is higher than the preset temperature information, the magnetic signal will be correspondingly reduced; when the temperature information is lower than the preset temperature information, the magnetic signal will be correspondingly increased. The temperature information collected by the temperature sensor 132 can be used to correct the magnetic signal at the back end, or can be calibrated in the geomagnetic sensor circuit 100 (such as the interface unit 180 ), and then transmitted to the back end after the calibration is completed.

The temperature sensor 132 itself may also be used to correct the obtained temperature information of the geomagnetic sensor circuit 100 . The obtained temperature information of the geomagnetic sensor circuit 100 may be corrected according to the ambient temperature of the geomagnetic sensor circuit 100 . For example, when the ambient temperature is higher than the temperature information of the geomagnetic sensor circuit 100 , the obtained temperature information of the geomagnetic sensor circuit 100 may be correspondingly lowered. When the ambient temperature is lower than the temperature information of the geomagnetic sensor circuit 100 , the obtained temperature information of the geomagnetic sensor circuit 100 may be correspondingly increased. The obtained temperature information of the geomagnetic sensor circuit 100 may also be corrected according to the historical temperature of the geomagnetic sensor circuit 100 . The obtained temperature information of the geomagnetic sensor circuit 100 may also be corrected according to the temperature curve of the current temperature information of the geomagnetic sensor circuit 100 . For example, when the temperature curve is a rising curve, the obtained temperature information of the geomagnetic sensor circuit 100 may be correspondingly lowered. When the temperature curve is a descending curve, the obtained temperature information of the geomagnetic sensor circuit 100 may be adjusted accordingly. Through the above method, the accuracy of the acquired temperature information can be controlled within 0.1 degrees Celsius, which improves the test accuracy.

The coil area of the second magnetic sensor 124 may be larger than the coil area of the first magnetic sensor 122 , so that the range of the magnetic signal obtained by the second magnetic sensor 124 is larger than the range of the magnetic signal obtained by the first magnetic sensor 122 .

The number of coils of the second magnetic sensor 124 is smaller than the number of coils of the first magnetic sensor 122 , so that the range of the magnetic signal obtained by the second magnetic sensor 124 is larger than the range of the magnetic signal obtained by the first magnetic sensor 122 .

The coil area of the second magnetic force sensor 124 can be greater than the coil area of the first magnetic force sensor 122, meanwhile, the coil quantity of the second magnetic force sensor 124 is less than the coil quantity of the first magnetic force sensor 122, to realize the magnetic force signal that the second magnetic force sensor 124 acquires The range is larger than the range of the magnetic signal acquired by the first magnetic sensor 122 .

It should be noted that the second magnetic sensor 124 can also measure large magnetic flux changes, the magnetic signal range obtained by the second magnetic sensor 124 is larger than the magnetic signal range obtained by the first magnetic sensor 122, but the measurement accuracy will be lower than that of the first magnetic sensor. sense of measurement accuracy.

Please refer to FIG. 3 . FIG. 3 is a schematic diagram of a third structure of a geomagnetic sensor circuit provided in an embodiment of the present application. The geomagnetic sensor circuit 100 may further include a third magnetic sensor 126, the third magnetic sensor 126 acquires a third magnetic signal, and the third magnetic signal is used to calculate the magnetic signal in cooperation with the first magnetic signal. The range of the magnetic signal obtained by the third magnetic signal is the same as the range of the magnetic signal obtained by the first magnetic sensor 122 . The third magnetic signal can cooperate with the first magnetic signal to achieve high-precision detection. When the value difference between the first magnetic signal and the third magnetic signal exceeds the threshold value, it will be re-detected. When the value difference between the first magnetic signal and the third magnetic signal exceeds the valve When the value is within the range, you can calculate the average output or multiply the corresponding weight output. For example, the weight of the first magnetic force signal is 0.6, and the weight of the third magnetic force signal is 0.4.

It can be understood that the first magnetic sensor 122, the second magnetic sensor 124 and the third magnetic sensor 126 can detect the magnetic signals in the three directions of X\Y\Z, which can also be understood as the first magnetic signal, the second magnetic signal Both the third magnetic force signal and the third magnetic force signal include magnetic force signals in three directions of X\Y\Z.

The interface unit 180 may include an I2C interface or an I3C interface. The geomagnetic sensor circuit 100 is electrically connected with other devices through the interface unit 180 , and transmits the magnetic force signal acquired by the geomagnetic sensor circuit 100 to other devices. For example, the geomagnetic sensor circuit 100 is electrically connected to the processor through the interface unit 180, and transmits the magnetic force signal to the processor. After the processor receives the magnetic force signal, it can adjust corresponding application programs, such as adjusting compass, games, navigation and other application programs. Among them, the I3C interface has a higher transmission speed, supports multiple working modes in terms of power consumption, and saves more power. In some embodiments, the interface unit 180 may be a serial interface (Serial Data Interface).

The geomagnetic sensor circuit 100 can also include a reset coil 134 (Reset coils), the reset coil 134 is used to restore the magnetic sensor element to a normal working state under the action of a strong magnetic field, and the magnetic field generated by driving the reset coil 134 restores the original performance of the sensor element, thus Can effectively improve the test accuracy.

The geomagnetic sensor circuit 100 may further include a test coil 136 (Test Coils), which is used to generate a reference magnetic field to test the sensor element for simple diagnosis.

The geomagnetic sensor circuit 100 may also include an on-chip voltage regulator 138 (Voltage Regulator), and the on-chip voltage regulator 138 supplies power to internal circuits.

The geomagnetic sensor circuit 100 may further include a reset unit 142 (Power-on Reset). The reset unit 142 is used to generate a signal to reset and initialize device registers through a power supply voltage ramp when the chip is powered on.

The geomagnetic sensor circuit 100 may also include an on-chip clock generator 144 (Clock Generator), which is used to generate a clock signal and provide it to internal circuits.

The geomagnetic sensor circuit 100 may also include a power down control 146 (Power Down Control) for controlling the voltage.

It can be understood that the geomagnetic sensor circuit includes a geomagnetic sensor chip. Please refer to FIG. 4 for details. FIG. 4 is a fourth structural schematic diagram of the geomagnetic sensor circuit provided by the embodiment of the present application. The geomagnetic sensor chip 190 includes a first magnetic sensor 122 , a second magnetic sensor 124 , a second magnetic sensor 124 , an amplifier 140 , an analog-to-digital converter 160 and an interface unit 180 . It can also be understood that the geomagnetic sensor chip 190, the geomagnetic sensor chip 190 includes the first magnetic sensor 122, the second magnetic sensor 124, the second magnetic sensor 124, the amplifier 140, the analog-to-digital converter 160 and the interface unit 180 integrated in the geomagnetic sensor chip Within 190.

Certainly, the geomagnetic sensor circuit 100 in the above-mentioned embodiment can be integrated in a geomagnetic sensor chip 190, the integration is higher, the volume can be made small, does not take up space, and the space utilization rate is improved. At the same time, because the geomagnetic sensor circuit 100 is integrated In one geomagnetic sensor chip 190, the stability is better and the anti-interference ability is also stronger.

Please refer to FIG. 5 , which is a schematic circuit diagram of a geomagnetic sensor circuit provided in an embodiment of the present application. The geomagnetic sensor circuit 100 may include a geomagnetic sensor chip 190 and a peripheral matching circuit. Specifically, the geomagnetic sensor chip includes a power supply pin (VDD), a first reset pin (VCAP), a second reset pin (VPP), a test pin (TEST), a null pin (NC), a communication pin ( SDA, SCL), ground pin (VSA).

The second reset pin can be connected with a series resistor R2507 to reduce the effect of overshoot.

The power supply pin is connected to the pull-up resistor R2515, and at the same time connects the capacitor C2507 (1uF) to the ground for stabilizing the input voltage.

The first reset pin connects the capacitor C2505 (4.7uF) to the ground, and also connects to the first voltage terminal (VIO28-PMU). The first reset pin is the reset power supply pin of the geomagnetic sensor device. The Anisotropic Magnetoresistive Sensor (AMR) technology device is easily magnetized by the external magnetic field. In the chip design, the capacitor discharges the first reset pin to reset ( reset), to eliminate the influence of external magnetic field interference. The reset current is 500-600mA, and the maintenance time is 0.4uS. Since the reset of the device will draw current from the capacitor terminal, a voltage drop (that is, ripple) will appear at the first reset pin. The reset strategy selected by the geomagnetic sensor circuit 100 is to reset after detecting magnetic saturation. In related technologies, some equipment platforms do not have a sensor hub (sensor hub), and need to use the G-sensor to assist, specifically: when it is detected that the G-sensor has data changes, but the geomagnetism does not move, it is judged as geomagnetic saturation. Therefore, the device performs reset calibration, but the G-sensor must be turned on all the time. Another part of the platform uses a fixed time interval to reset, reset every 5s. The reset strategy selected by the geomagnetic sensor circuit 100 in this embodiment is to reset after detecting magnetic saturation, which has higher accuracy and is compatible with different platforms. Only reset. It should be noted that when the detected magnetic flux is greater than 95% of the maximum range, it can be considered magnetic saturation. The device platform may be understood as a chip platform of the electronic device 300, such as an MTK platform, a Qualcomm platform, and the like.

AMR technology can be understood as, when the external magnetic field and the built-in magnetic field of the magnet form a zero-degree angle, the resistance will not change with the change of the external magnetic field; but when the external magnetic field has a certain angle with the built-in magnetic field of the magnet, The magnetization vector inside the magnet will shift and the sheet resistance will decrease. This characteristic is called anisotropic magnetoresistance effect.

The communication pins (SDA, SCL) are I2C or I3C communication pins, and the NC pin can select different I2C or I3C addresses by connecting high level and ground.

The embodiment of the present application further provides a circuit board, please refer to FIG. 6 for details. FIG. 6 is a schematic structural diagram of the circuit board provided in the embodiment of the present application. The circuit board 200 includes a substrate 220 and the geomagnetic sensor circuit 100 . The geomagnetic sensor circuit 100 may be the geomagnetic sensor circuit 100 in any of the above-mentioned embodiments.

Capacitors (C2505, C2507) in the geomagnetic sensor circuit 100 are placed close to the geomagnetic sensor chip. When the geomagnetic sensor chip is far away from the device platform processor, and the interface unit (such as I2C or I3C) has a long line or is close to the antenna, the interface unit The two signal lines (SDA, SCL) are routed in parallel, and ground wires are added to both sides of the two signal lines for protection to avoid high-speed signal lines on adjacent layers. When using the geomagnetic sensor chip for the first time, start to connect 0 ohm resistors in series on the two signal lines, cancel after the small batch process verification test (Pilot-run Verification Test, PVT), and pay attention to prevent address conflicts.

The circuit board 200 also includes a power supply module 230, the geomagnetic sensor circuit 100 includes a power supply pin, and the power supply pin and the power supply module 230 are connected by a power supply wiring 240. The circuit board 200 is also provided with a signal line 250 and a power supply wiring 240. Set apart from the signal line 250 . specific:

1) When the current variation range of the power supply wiring can reach 10mA, the safe distance from the surrounding signal lines should be more than 3mm;

2) When the current variation range of the power supply wiring can reach 50mA, the safe distance from the surrounding signal lines should be more than 7mm;

3) When the current variation range of the power supply wiring can reach 100mA, the safe distance from the surrounding signal lines should be more than 10mm;

4) When the current variation range of the power supply wiring can reach 200mA, the safe distance from the surrounding signal lines should be more than 20mm.

The geomagnetic sensor circuit 100 and the capacitor connected to the power supply pin can be placed inside the shielding cover 260 (the main shielding cover or a separate small shielding cover closed all around, and the shielding cover can be made of nickel-nickel copper or other materials), compared to placing it under the bow-shaped shielding bracket , can prevent the geomagnetic sensor circuit 100 and the capacitor connected to the power supply pin from being corroded after the device is infiltrated with liquid.

The circuit board 200 is also provided with a preset magnetic component 270 , and the geomagnetic sensor circuit 100 is arranged at intervals from the preset magnetic component 270 . The geomagnetic sensor circuit 100 should be as far away from magnetic devices as possible, or avoid using magnetic devices. The preset magnetic components 270 can include magnetic devices with hard iron materials such as receivers, speakers, magnetic switches, rotating shafts, camera modules, and vibration motors. , TV antenna, inductor, Hall switch and so on. In addition, devices containing soft iron materials such as LCD, RF shielding frame, memory card holder, SIM card holder, various connectors, shafts, batteries, NFC antennas and other metal structural parts, etc. Before layout, probes can be used to measure the magnetic field strength of each device to find a suitable position. For example, the geomagnetic sensor circuit 100 may be disposed on the periphery of the circuit board 200 . The distance between the geomagnetic sensor circuit 100 and other magnetic devices can be:

1) The safety distance from the magnetic switch device is more than 20mm;

2) The safe distance from the speaker is 10-20mm;

3) The safe distance from the vibration motor is more than 10mm;

4) The safe distance from the camera module is more than 10mm;

5) The safe distance from the memory card holder is more than 5mm;

6) The safe distance from the magnetic shielding frame is more than 10mm;

7) The safe distance from the receiver is more than 10mm;

8) The safe distance from the large inductance is more than 5mm;

9) The safety distance of the rotating shaft is more than 10mm;

10) More than 15mm away from the NFC antenna;

11) 5mm away from the soft magnetic material such as the bending edge of the LCD frame (if the requirements cannot be met, the LCD should use non-magnetic materials;

12) 10mm away from switching power supply.

The geomagnetic sensor circuit 100 of this embodiment (the improved geomagnetic sensor circuit) has obvious advantages over the geomagnetic sensor circuit in the prior art (the geomagnetic sensor circuit before the improvement). The geomagnetic sensor chip in the geomagnetic sensor circuit 100 of this embodiment adopts a highly integrated process, which is more integrated and smaller in size. The first magnetic sensor, the second magnetic sensor and the third magnetic sensor in the geomagnetic sensor circuit 100 are used to measure the magnetic field strength, and the first magnetic sensor and the third magnetic sensor are used to measure a small range to achieve high precision, and the second magnetic sensor is used It is suitable for measuring a large range and supports a large range of measurements. The geomagnetic sensor circuit 100 adds temperature compensation, which is accurate to 0.1 degree, and the temperature compensation is more accurate. The internal packaging of the geomagnetic sensor circuit 100 has good shielding performance, strong anti-interference ability and high reliability. The geomagnetic sensor circuit 100 supports a low power consumption mode with lower power consumption. The geomagnetic sensor circuit 100 is compatible with various device platforms. Table 1 below is an illustrative example.

Table 1: Angle data

The standard deviation of the improved geomagnetic sensor in the X direction STDRV-X=0.140, the standard deviation of the geomagnetic sensor in the X direction STDRV-X=0.171; the standard deviation of the improved geomagnetic sensor in the Y direction STDRV-Y=0.152 before improvement The standard deviation of the geomagnetic sensor in the Y direction STDRV-Y=0.223; the standard deviation of the improved geomagnetic sensor in the Z direction STDRV-Z=0.187 the standard deviation of the geomagnetic sensor in the Z direction STDRV-Z=0.264; the improved geomagnetic sensor angle The accuracy is also higher, and the performance of the improved geomagnetic sensor has been significantly improved.

It should be noted that only part of the signal lines and part of the preset magnetic components are shown on the circuit board shown in the figure.

The embodiment of the present application also provides an electronic device, a housing of the electronic device and a circuit board, the circuit board is installed in the housing, and the circuit board may be the circuit board in any of the foregoing embodiments.

The electronic device may be a mobile terminal such as a smart phone or a tablet computer, and may also be a game device, an augmented reality (Augmented Reality, AR) device, a virtual reality (Virtual Reality, VR) device, a data storage device, an audio playback device, or a video playback device. , wearable devices and other devices with display devices, wherein the wearable devices may be smart bracelets, smart glasses, smart watches, smart decorations, and the like. In the following, an electronic device such as a mobile phone is taken as an example for description. Please refer to FIG. 7 and FIG. 8 for details. FIG. 7 is a schematic structural diagram of an electronic device provided by an embodiment of the present application, and FIG. 8 is a schematic diagram of another side of the electronic device shown in FIG. 7 . The electronic device 300 also includes a display screen 310 , a casing 320 , a main board 330 and a battery 340 .

Wherein, the casing 320 includes a frame 322 and a rear cover 324 . The display screen 310 and the rear cover 324 are located on opposite sides of the electronic device 300 . The electronic device 300 also includes a middle board, and a frame 320 is arranged around the middle board. The frame 320 and the middle board may form a middle frame of the electronic device 300 . The middle board and the frame 320 respectively form an accommodating chamber on both sides of the middle board. One accommodating chamber accommodates the display screen 310 , and the other accommodating chamber accommodates the main board 330 , battery 340 and other electronic components or functional modules of the electronic device 300 .

The middle plate may be in the form of a thin plate or sheet, or may be a hollow frame structure. The middle frame is used to provide support for the electronic components or functional components in the electronic device 300 , so as to install the electronic components and functional components in the electronic device 300 together. Functional components such as camera components, receivers, circuit boards, and batteries of the electronic device 300 can be installed on the middle frame or the main board 330 for fixing. It can be understood that the material of the middle frame may include metal or plastic.

The main board 330 can be installed on the middle frame. One or more functional components such as a microphone, a speaker, an earphone jack, a camera component, an acceleration sensor, a gyroscope, and a processor may be integrated on the main board 330 . Meanwhile, the display screen 310 can be electrically connected to the main board 330 so as to control the display of the display screen through the processor on the main board 330 .

The battery 340 may be mounted on the middle frame. Meanwhile, the battery 340 is electrically connected to the main board 330 , so that the battery 340 supplies power to the electronic device 300 . Wherein, the main board 330 may be provided with a power management circuit. The power management circuit is used to distribute the voltage provided by the battery 340 to various electronic components in the electronic device 300 .

The display screen 310 forms a display surface of the electronic device 300 and is used for displaying information such as images and texts. The display screen 310 may be a liquid crystal display (Liquid Crystal Display, LCD) or an organic light-emitting diode display (Organic Light-Emitting Diode, OLED) or other type of display.

The display screen 310 may be a special-shaped screen, and the display screen 310 may include a display area 312 and a non-display area 314 . Wherein, the display area 312 performs the display function of the display screen 310 for displaying information such as images and texts. The non-display area 314 does not display information, and the non-display area 314 is used to cooperate with the front camera module 382 to work. For example, the non-display area 314 is a highly light-transmitting area, and the front camera module 382 can obtain images of the outside world through the non-display area 314 , such as taking pictures and video recordings. In some other embodiments, the display screen can be a full screen, that is, the front of the display screen is basically all the display area, and the display area of the display screen is consistent, and the front camera module can be moved from the electronic device to the electronic device using a driving mechanism. Recording outside the device. The display area of the display screen can also include a main display area and an auxiliary display area. The light transmittance of the auxiliary display area is greater than the light transmittance of the main display area. The front camera module is set corresponding to the auxiliary display area. Below, the secondary display area can display images in conjunction with the main display area. When the secondary display area does not display images, the camera module can take pictures through the secondary display area. For example, the non-display area shown in Figure 7 can be replaced by a secondary Display area.

The electronic device 300 also includes a rear camera module 384 , the rear cover 324 is provided with a light-transmitting area corresponding to the rear camera module 384 , and the rear camera module 384 can obtain external images through the light-transmitting area of the rear cover 324 .

It can be understood that the main board in this embodiment may be the circuit board in the above embodiment, and the circuit board in the above embodiment may also be other circuit boards in the electronic device.

In the description of the present application, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of said features. In the description of this application, "plurality" means two or more.

The geomagnetic sensor circuit, circuit board and electronic equipment provided in the embodiments of the present application have been introduced in detail above. In this paper, specific examples are used to illustrate the principles and implementation methods of the present application, and the descriptions of the above embodiments are only used to help understand the present application. At the same time, for those skilled in the art, based on the idea of this application, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be construed as limiting the application.

Claims (12)

1. A geomagnetic sensor circuit, characterized in that, comprises a geomagnetic sensor chip, and the geomagnetic sensor chip comprises: a first magnetic sensor, configured to acquire a first magnetic signal; The second magnetic sensor is used to obtain a second magnetic signal, and the range of the magnetic signal obtained by the second magnetic sensor is larger than the range of the magnetic signal obtained by the first magnetic sensor; The third magnetic force sensor is used to acquire a third magnetic force signal, the range of the magnetic force signal acquired by the third magnetic force sensor is the same as the range of the magnetic force signal acquired by the first magnetic force sensor, when the first magnetic force signal and the third magnetic force signal When the value difference of the magnetic signal is within the threshold range, the average value is output or multiplied by the corresponding weight to output the magnetic signal; An amplifier, the first magnetic sensor, the second magnetic sensor and the third magnetic sensor are all connected to the input of the amplifier, and the amplifier is used to amplify the signal input to the amplifier; An analog-to-digital converter, the input of the analog-to-digital converter is connected to the output of the amplifier, and the analog-to-digital converter is used to obtain the amplified signal of the amplifier and convert the amplified signal into a digital signal; and an interface unit connected to the output end of the analog-to-digital converter, the interface unit is used to obtain the digital signal converted by the analog-to-digital converter, and transmit the digital signal; The first reset pin, the first reset pin is used for grounding through the first capacitor, and the first reset pin is also used for connecting the first voltage terminal. When the magnetic sensor chip is saturated, the first reset pin is connected to the first voltage terminal. A reset pin is reset by discharging the first capacitor; The second reset pin is connected to a series resistor and is used to receive a reset signal through the series resistor; The reset coil is used to restore the magnetic sensor element to a normal working state under the action of a strong magnetic field; a test coil for generating a reference magnetic field for testing the magnetic sensor element; The reset unit is used for generating a signal through a power supply voltage ramp to reset and initialize device registers when the geomagnetic sensor chip is powered on. 2. The geomagnetic sensor circuit according to claim 1, wherein the geomagnetic sensor circuit also includes a temperature sensor, the temperature sensor is used to obtain temperature information of the geomagnetic sensor circuit, and the temperature sensor and the The interface unit is connected, and the interface unit is used to acquire the temperature information of the temperature sensor, correlate the temperature information with the digital signal, and then transmit it. 3. The geomagnetic sensor circuit according to claim 1, wherein the geomagnetic sensor circuit also includes a temperature sensor, the temperature sensor is used to obtain the current temperature information of the geomagnetic sensor circuit, and the temperature sensor is connected to the geomagnetic sensor circuit The interface unit is connected to the interface unit, and the interface unit is used to obtain the temperature information of the temperature sensor, adjust the digital signal according to the temperature information, and transmit the adjusted digital signal. 4 . The geomagnetic sensor circuit according to claim 1 , wherein the amplifier is an adjustable magnification amplifier, and the amplifier is used to amplify different signals input to the amplifier with different magnifications. 5. The geomagnetic sensor circuit according to claim 1, wherein the coil area of the second magnetic sensor is greater than the coil area of the first magnetic sensor; and / or The number of coils of the second magnetic sensor is smaller than the number of coils of the first magnetic sensor. 6. The geomagnetic sensor circuit according to claim 1, wherein the interface unit comprises an I2C interface or an I3C interface. 7. A circuit board, characterized in that, comprising: Substrate; The geomagnetic sensor circuit is arranged on the substrate, and the geomagnetic sensor circuit is the geomagnetic sensor circuit described in any one of claims 1-6. 8 . The circuit board according to claim 7 , wherein a shielding cover is further provided on the circuit board, and the geomagnetic sensor circuit is arranged in the shielding cover. 9. The circuit board according to claim 7, wherein the interface unit comprises two signal lines, and the two signal lines are arranged in parallel. 10 . The circuit board according to claim 7 , wherein a preset magnetic component is further provided on the circuit board, and the geomagnetic sensor circuit is spaced apart from the preset magnetic component. 11 . 11. The circuit board according to claim 7, characterized in that, the circuit board also includes a power supply module, the geomagnetic sensor circuit and the power supply module are connected by power wiring, and the circuit board also includes A signal line is provided, and the power supply line is spaced apart from the signal line. 12. An electronic device, characterized in that it comprises: casing; and A circuit board is installed in the housing, and the circuit board is the circuit board described in any one of claims 7-11.

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