TFT LCD bicycle instrument

Abstract

The utility model discloses a TFT LCD screen bicycle instrument, including casing and install on casing's TFT LCD screen, and the inside of casing is equipped with control circuit and data storage circuit, control circuit is equipped with MCU control chip, data storage circuit is connected with MCU control chip, control circuit is connected with switch -on off detection circuit and data processing circuit, switch -on off detection circuit connects power management circuit, data processing circuit passes through CAN circuit transmission data to display circuit, display circuit includes TFT LCD display screen circuit and back light power, is provided with the tyre pressure display, the speed display and various essential pilot lamp on TFT LCD display screen. This patent is through wide voltage input, CAN communication redundancy, environmental light self -adaptation adjustment and data storage circuit zoning management design, has solved traditional instrument compatibility, communication is susceptible to interference, back light energy consumption is high and data security low etc.

Description

Technical Field

[0001] This utility model relates to the field of electric bicycle instrument technology, specifically to a TFT LCD screen bicycle instrument. Background Technology

[0002] Bicycles, as a very primitive means of transportation, have a long history and are widely used for short-distance travel. Bicycles are divided into electric bicycles and non-electric bicycles, and the bicycle dashboard is an essential device for electric bicycles. Currently, most bicycle dashboards only support 12V / 24V input, are incompatible with 48V lithium battery systems, and only serve the function of displaying vehicle information such as cumulative mileage, battery level, and speed. Generally, electric bicycles do not have data storage capabilities when they leave the factory, meaning they cannot view current or historical records of abnormal driving events, which is quite inconvenient for electric bicycle users with diverse travel needs. Drivers are easily affected by the driving environment and road conditions. When riding on bumpy roads or mountainous terrain, drivers can only observe the vehicle's operating status through the dashboard. If the vehicle exhibits abnormal driving behavior, it is impossible to check for and prevent incidents based on the current fault. Furthermore, the dashboard is easily affected by ambient light, reducing its practicality and versatility.

[0003] Chinese patent document CN220701264U discloses "An FPC LCD Screen Motorcycle Instrument Panel." This motorcycle instrument panel's LCD screen is connected to an FPC board, which has a control circuit and a control chip. The LCD screen includes a vehicle tilt angle display module connected to a CAN circuit. The control chip is connected to a signal acquisition circuit, which is connected to an external interface. The control chip is also connected to a Bluetooth circuit. The LCD screen features a mobile phone caller ID module and a simple navigation module. The instrument panel includes a vehicle tilt angle display module, a mobile phone caller ID module, a simple navigation module, and various essential indicator lights. However, this technical solution, applied to the motorcycle instrument panel field, only includes a basic display module and a simple navigation module. Its functionality cannot meet the actual needs of bicycles or sports bicycles in complex environments, and it suffers from low instrument panel compatibility. Summary of the Invention

[0004] This invention proposes a TFT LCD screen bicycle instrument, which aims to solve the problems of poor compatibility, communication susceptibility to interference, high backlight power consumption, and low data security of traditional instruments through wide voltage input, CAN communication redundancy, ambient light adaptive adjustment, and data storage circuit partition management design. It is suitable for electric bicycles and sports bicycles in complex environments.

[0005] To achieve the above objectives, this utility model proposes a TFT LCD screen bicycle instrument, including a housing and a TFT LCD screen mounted on the housing. The housing contains a control circuit and a data storage circuit. The control circuit has an MCU control chip. The data storage circuit is connected to the MCU control chip. The control circuit is connected to a power-on / off detection circuit and a data processing circuit. The power-on / off detection circuit is connected to a power management circuit. The data processing circuit transmits data to the display circuit through a CAN circuit.

[0006] The MCU control chip is a Qinheng CH32V208RBT6. As the main control MCU, the Qinheng CH32V208RBT6 is responsible for: processing sensor signals (steering, tire pressure, light, vehicle speed, etc.); communicating with other devices via the CAN bus to receive or send data; driving the TFT LCD screen; controlling the displayed content (such as vehicle speed, tire pressure, and steering indication) via parallel or SPI interface; and supporting SWD debugging interfaces (SWCLK, SWDIO) and UART firmware updates (UART4_TX / RX).

[0007] Preferably, the data storage circuit is connected to the control circuit, including an EEPROM memory chip. One end has three device address configuration pins and a ground pin all grounded, while the other end has SCL and SDA pins connected to the MCU control chip via an I2C bus. The I2C bus is equipped with pull-up resistors R22 and R23. The VCC1 pin is connected to power supply filter capacitors C21 and C22. The write protection pin WP is connected to a low level to enable writing.

[0008] The data storage of this instrument is achieved by the above-mentioned data storage circuit and SPI FLASH, where SPI FLASH is used to store firmware or configuration data; and EEPROM storage chip is used to store user settings or calibration parameters.

[0009] Preferably, the power-on / off detection circuit is connected to the power management circuit and includes vehicle ignition signal input and signal output pins. A voltage divider resistor and a pull-down resistor are provided between the vehicle ignition signal input and signal output pin circuits. The voltage divider resistors 2R1 and 2R3 reduce the high-level signal to a logic level acceptable to the MCU control chip, and the pull-down resistor 2R2 ensures that the output pin remains at a low level when there is no signal input.

[0010] When the vehicle is ignited, the power-on / off detection circuit uses voltage divider resistors and pull-down resistors to safely convert the vehicle's high-voltage ignition signal IGN(+) into a logic level (ICN_AD) that the MCU can recognize, thus achieving reliable detection of the power-on / off status. When the MCU detects a high level, it starts the system; when it detects a low level, it enters a low-power mode.

[0011] Preferably, the power management circuit has an input voltage range of 8~60V, which is stepped down to 3.3V by a DC-DC conversion circuit to power the MCU control chip and TFT LCD screen.

[0012] Preferably, the power management circuit specifically includes a feedback network and an LDO regulator. The feedback network sets the conversion output voltage through voltage divider resistors 1R4 and 1R5, and the LDO regulator steps down the voltage to 3.3V. The DC-DC conversion circuit connects an EMI suppression circuit and a filter circuit. The filter circuit consists of multiple capacitors connected in parallel. The EMI suppression circuit includes TVS diodes TVS1 and TVS3 connected in parallel at the input stage to suppress surge voltage, and LC filter networks 1L1 and 1C6 to filter out high-frequency noise.

[0013] The aforementioned power management circuit has an input range of 8~60V, covering 12V / 24V lead-acid batteries and 48V lithium battery systems for electric bicycles, and even generator power supply scenarios, making it highly versatile. Furthermore, it includes feedback regulation and filtering design to ensure voltage stability and anti-interference capabilities.

[0014] Preferably, the data processing circuit includes a tire pressure module circuit and a vehicle speed circuit, as well as an ambient light detection circuit and a turn signal circuit. The tire pressure module circuit includes an SPI FLASH chip, which communicates with the MCU control chip via an SPI interface, and stores abnormal data in the data storage circuit EEPROM. The vehicle speed circuit is connected to the control circuit and includes diodes and transistors, as well as voltage divider resistors and matching resistors. The diodes 5D2 and 5Q6 suppress electromagnetic interference, and the voltage divider resistors and matching resistors adjust the signal level. The ambient light detection circuit is connected to the MCU control chip via a ZM_IN interface and includes a photosensor and a resistor-capacitor combination. The photosensor changes its resistance value according to the light intensity, the resistor converts the photosensor's resistance value into a voltage signal, and the capacitor is a filter capacitor. The turn signal circuit includes a left turn signal circuit and a right turn signal circuit, as well as a position light signal circuit and a high beam signal circuit.

[0015] Preferably, the turn signal circuit includes a left turn signal circuit and a right turn signal circuit, as well as a position light signal circuit and a high beam signal circuit; one end of the left turn signal circuit is connected to an external left turn signal, and the other end is connected to an MCU control chip; one end of the right turn signal circuit is connected to an external right turn signal, and the other end is connected to an MCU control chip; one end of the position light signal circuit is connected to an external position light, and the other end is connected to an MCU control chip; one end of the high beam signal circuit is connected to an external high beam, and the other end is connected to an MCU control chip.

[0016] The aforementioned data processing circuit primarily serves as sensor input. Specifically, left and right turn signal signals, position lights, and high beam signals are input to the MCU via voltage divider resistors and filter circuits. The tire pressure module communicates with the MCU via a dedicated SPI circuit. The ambient light detection circuit (such as a photoresistor or sensor) is input via ZM_IN and is used to automatically adjust screen brightness. The vehicle speed signal is input via the ADC pin, originating from a Hall sensor or encoder, and its output pulse frequency is proportional to the vehicle speed.

[0017] Preferably, the CAN circuit is connected to the control circuit, and the CAN transceiver chip converts the TTL level signal of the MCU control chip into a differential signal of the CAN bus. Specifically, it includes a CAN transceiver chip and a TVS diode. The CAN transceiver chip processes the MCU control chip level signal after it has been filtered by a filter capacitor. The TVS diode is connected to the CAN bus terminating resistor and the filter capacitor, and a common-mode inductor L8 is provided in the middle to suppress bus noise.

[0018] The aforementioned CAN communication circuit module features an anti-interference design, with parallel terminating resistors RN7 on the CANH / CANL lines for impedance matching to reduce reflections; its CAN transceiver chip SIT1051T also supports standby mode, controlled by the CAN_STBY pin.

[0019] Preferably, the display circuit includes a TFT LCD screen display circuit and a backlight power supply. The TFT LCD screen display circuit mainly includes an LCD module and multiple RN connection circuits, wherein the LCD module is connected to the MCU control chip and the multiple RN connection circuits; one end of the backlight power supply is connected to the TFT LCD screen display circuit, and the other end is connected to the control circuit.

[0020] Preferably, the backlight power supply includes a MOSFET 4Q1 and a transistor 4VT1. The input PWM signal is provided by an MCU control chip. The MOSFET 4Q1 controls the LED backlight on / off and brightness through the PWM signal. The transistor assists in current regulation. The backlight power supply also includes a filter capacitor to smooth the PWM signal and suppress noise.

[0021] The aforementioned LCD display circuit incorporates backlight power control to achieve adaptive backlight adjustment: the TFT LCD screen is directly driven by the MCU to display riding information; the backlight circuit uses PWM dimming, combined with an ambient light detection circuit to achieve automatic brightness adjustment, reducing the power consumption of the instrument.

[0022] Compared with the prior art, the beneficial effects achieved by this utility model are as follows: High compatibility and stability: Supports a wide voltage input of 8~60V, adapting to complex power supply environments (such as electric bicycles and generators). Low power consumption and high reliability: CAN communication standby mode reduces static power consumption, ambient light detection combined with backlight adaptive adjustment saves energy; TVS diodes and filter circuits ensure surge and EMI resistance. Data security and scalability: SPI Flash and EEPROM partitioned storage, write protection for critical parameters, support for remote firmware upgrades, and multiple sensor interfaces for easy function expansion; Therefore, this utility model is applicable to electric bicycles and sports bicycles, and can achieve high reliability, low power consumption and high compatibility of riding information management in complex environments, thus possessing significant market competitiveness. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the TFT LCD screen bicycle instrument structure of Embodiment 1 of this utility model.

[0024] Figure 2 This is a schematic diagram of the internal circuit architecture of Embodiment 2 of this utility model.

[0025] Figure 3 This is a pin diagram of the MCU control chip of the control circuit in Embodiment 2 of this utility model.

[0026] Figure 4 This is the power-on / off detection circuit of Embodiment 2 of this utility model.

[0027] Figure 5 This is the power management circuit of Embodiment 2 of this utility model.

[0028] Figure 6 This is the data storage circuit EEPROM of Embodiment 2 of this utility model.

[0029] Figure 7 This is the CAN circuit of Embodiment 2 of this utility model.

[0030] Figure 8 This is the display circuit of Embodiment 2 of this utility model.

[0031] Figure 9 This is the data processing circuit of Embodiment 2 of this utility model.

[0032] In the diagram: 1. TFT LCD screen; 2. Housing; 3. Mounting arm; 4. Mounting hole; 5. Screw mounting hole. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only one preferred embodiment of this utility model and are only used to explain the technical solutions of this utility model. They do not limit the scope of protection of this utility model. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0034] Example 1: This utility model provides a TFT LCD screen bicycle instrument panel, including a housing and a TFT LCD screen mounted on the housing, such as... Figure 1 As shown: The backlight of the TFT LCD screen 1 should be pure white light with uniform brightness; the surface of the LCD screen should be free of obvious scratches or debris, and there should be no bright spots affecting the reading within the visible area, with a total number of bright spots ≤ 3 and a diameter < 0.3mm; the optimal viewing angle of the LCD screen is at the 12 o'clock position, and there is a circular main switch for the instrument to the left of the optimal viewing angle, used to control the instrument's power on and off; the LCD screen displays numbers and characters with clear contrast, without ghosting (shadows) or missing strokes; the instrument should be free of dust and debris, and the LCD screen and transparent plate should be free of obvious fingerprints, scratches, and cracks.

[0035] The TFT LCD screen 1 is fitted with a housing 2. The housing is a one-piece injection molded plastic part. The plastic part should be free of burrs, flash, shrinkage marks, and bubbles that may affect the appearance or assembly. Two identical symmetrical mounting arms 3 are connected to the back of the housing. The bicycle instrument can be mounted on the handlebar of the bicycle. It is fitted into the appropriate position on the handlebar through the mounting holes 4 and pressed tightly through the screw mounting holes 5 to ensure that the instrument is firmly installed and will not fall off.

[0036] Example 2: As Figure 2-9 As shown in the figure, the internal circuit structure diagram of the TFT LCD screen bicycle instrument housing proposed in this utility model is as follows. Figure 2 As shown: The entire instrument cluster revolves around the control circuit. The MCU control chip within this circuit connects to a power-on / off detection circuit, a data storage circuit, a CAN circuit, an LCD display circuit, a backlight power supply, an ambient light detection circuit, a turn signal circuit, a tire pressure module circuit, and a vehicle speed circuit. The power-on / off detection circuit is connected to the power management circuit. The data processing circuit (ambient light detection circuit, turn signal circuit, tire pressure module circuit, and vehicle speed circuit) transmits data to the display circuit (LCD display circuit and backlight power supply) via the CAN circuit. The control circuit operates at a voltage range of DC 8-60V, with a typical operating current of 150~300mA and a maximum current of <500mA.

[0037] like Figure 3As shown, the control circuit chip model used in this embodiment is Qinheng CH32V208RBT6, which serves as the main control MCU. Its main responsibilities include: processing sensor signals (steering, tire pressure, light, vehicle speed, etc.); communicating with other devices via the CAN bus to receive or send data; driving the TFT LCD screen; controlling the displayed content (such as vehicle speed, tire pressure, steering indication) via parallel port or SPI interface; and supporting SWD debugging interface (SWCLK, SWDIO) and UART firmware updates (UART4_TX / RX).

[0038] Specifically, the circuit modules connected to the MCU control chip in the control circuit are as follows: (1) Power on / off detection circuit like Figure 4 As shown, the power-on / off detection circuit is connected to the power management circuit, including the vehicle ignition signal input IGN(+) and the signal output pin ICN_AD. A voltage divider resistor 2R1, 2R3 and a pull-down resistor 2R2 are provided between the vehicle ignition signal input and the signal output pin circuit. The voltage divider resistors 2R1 and 2R3 reduce the high-level signal to a logic level acceptable to the MCU control chip, and the pull-down resistor 2R2 ensures that the output pin remains at a low level when there is no signal input.

[0039] When the vehicle is ignited, the power-on / off detection circuit uses voltage divider resistors and pull-down resistors to safely convert the vehicle's high-voltage ignition signal IGN(+) into a logic level (ICN_AD) that the MCU can recognize, thus achieving reliable detection of the power-on / off status. When the MCU detects a high level, it starts the system; when it detects a low level, it enters a low-power mode.

[0040] (2) Power management circuit like Figure 5 As shown, the power management circuit receives the vehicle's high-voltage ignition signal IGN(+), with an operating voltage range of 8~60V. This voltage is stepped down to 3.3V via a DC-DC converter circuit to power the MCU control chip and TFT LCD screen. Specifically, it includes a feedback network and an LDO regulator. The feedback network sets the output voltage using voltage divider resistors 1R4 and 1R5, which is then stepped down to 3.3V again by the LDO regulator. The DC-DC converter circuit connects an EMI suppression circuit and a filter circuit. The filter circuit consists of multiple capacitors connected in parallel. The EMI suppression circuit includes TVS diodes TVS1 and TVS3 connected in parallel at the input stage to suppress surge voltage, and an LC filter network 1L1 and 1C6 to filter out high-frequency noise.

[0041] The aforementioned power management circuit has an input range of 8~60V, covering 12V / 24V lead-acid batteries and 48V lithium battery systems for electric bicycles, and even generator power supply scenarios, making it highly versatile. Furthermore, it includes feedback regulation and filtering design to ensure voltage stability and anti-interference capabilities.

[0042] (3) Data storage circuit like Figure 6 As shown, the data storage circuit is connected to the control circuit MCU control chip. The main core component is an EEPROM memory chip. On one end, the three device address configuration pins (A0, A1, A2) and the ground pin GND are all grounded. On the other end, the SCL pin and SDA pin are connected to the MCU control chip via an I2C bus. The I2C bus is equipped with pull-up resistors R22 and R23. The VCC1 pin is connected to power supply filter capacitors C21 and C22. The write protection pin WP is connected to a low level to enable writing.

[0043] The data storage of this instrument is jointly implemented by the aforementioned data storage circuit and the SPI FLASH in the tire pressure module circuit. The SPI FLASH is used to store firmware or configuration data, and the EEPROM storage chip is used to store user settings or calibration parameters.

[0044] (4) CAN circuit like Figure 7 As shown, the CAN circuit connects to the CAN transceiver pins of the MCU control chip in the control circuit. The core component, the CAN transceiver chip SIT1051T / 3, converts the TTL level signal of the MCU control chip into a differential signal of the CAN bus. Specifically, it includes the CAN transceiver chip and the TVS diode TVS2. The CAN transceiver chip processes the MCU control chip level signal after it has been filtered by the filter capacitor. The TVS diode TVS2 is connected to the CAN bus terminating resistor and the filter capacitor, with a common-mode inductor L8 in between to suppress bus noise.

[0045] The aforementioned CAN communication circuit module features an anti-interference design, with parallel terminating resistors RN7 on the CANH / CANL lines for impedance matching to reduce reflections. Its CAN transceiver chip SIT1051T also supports standby mode, controlled by the CAN_STBY pin, reducing the quiescent current from 5mA to 50µA.

[0046] (5) Display circuit like Figure 8 As shown, the display circuit includes a TFT LCD screen display circuit and a backlight power supply. The adaptive backlight adjustment is achieved by combining the backlight power supply control: the TFT LCD screen is directly driven by the MCU to display riding information; the backlight circuit adopts PWM dimming, which, combined with the ambient light detection circuit in the data processing circuit, realizes automatic brightness adjustment and reduces the power consumption of the instrument.

[0047] like Figure 8As shown in (a), the TFT LCD screen display circuit mainly includes an LCD module, a grounding circuit and multiple RN connection circuits. The LCD module is connected to the MCU control chip and multiple RN connection circuits, and is also connected to the backlight power supply circuit through the LEDA and LEDK pins to control the brightness of the TFT LCD screen.

[0048] like Figure 8 As shown in (b), the core components of the backlight power supply mainly include a MOSFET 4Q1 and a transistor 4VT1. The input PWM_OUT signal is provided by the MCU control chip. The MOSFET 4Q1 controls the LED backlight on / off and brightness through the PWM signal. The transistor 4VT1 assists in current regulation. The backlight power supply also includes filter capacitors 4C1, 4C2, 4C3, and 4C4 to smooth the PWM signal and suppress noise. The MCU outputs a PWM signal (PWM_OUT) to the gate of 4Q1 to control its duty cycle. The PWM signal drives LEDA (anode) and LEDK (cathode) through 4Q1 to adjust the backlight brightness. The capacitors filter out high-frequency components of the PWM to prevent LED flicker.

[0049] (6) Data processing circuit like Figure 9 As shown, the data processing circuit includes a tire pressure module circuit and a vehicle speed circuit, as well as an ambient light detection circuit and a turn signal circuit; the turn signal circuit includes a left turn signal circuit and a right turn signal circuit, as well as a position light signal circuit and a high beam signal circuit.

[0050] The aforementioned data processing circuit primarily serves as sensor input. Specifically, left and right turn signal signals, position lights, and high beam signals are input to the MCU via voltage divider resistors and filter circuits. The tire pressure module communicates with the MCU via a dedicated SPI circuit. The ambient light detection circuit (such as a photoresistor or sensor) is input via ZM_IN and is used to automatically adjust screen brightness. The vehicle speed signal is input via the ADC pin, originating from a Hall sensor or encoder, and its output pulse frequency is proportional to the vehicle speed.

[0051] like Figure 9 As shown in (a), the ambient light detection circuit is connected to the MCU control chip through the ZM_IN interface. It includes a photosensitive sensor GD, resistors 3R26, 3R27, and 3R29, and a filter capacitor 3C1. The photosensitive sensor GD changes its resistance value according to the light intensity. The resistors 3R26, 3R27, and 3R29 convert the resistance value of the photosensitive sensor into a voltage signal. The filter capacitor 3C1 eliminates high-frequency interference. The photosensitive resistor and the fixed resistor 3R27 form a voltage divider circuit, which outputs an analog voltage to the MCU's ADC2. The MCU adjusts the PWM_OUT duty cycle according to the ADC value to achieve adaptive adjustment of the backlight brightness.

[0052] like Figure 9 As shown in Figure (b), the core circuit element of the tire pressure module circuit is an SPI FLASH chip. The chip pins are as follows: 1, CE#; 2, SO; 3, WP#; 4, GND; 5, SI; 6, SCK; 7, HOLD#; 8, VCC. Among them, CE#, WP#, and HOLD# are control signals used for chip enable, write protection, and data retention. The circuit communicates with the MCU control chip through the SPI interface (SPI_CS, SPI_CLK, SPI_MOSI, SPI_MISO) and outputs pressure and temperature data. The MCU periodically reads the tire pressure sensor data through the SPI bus, processes the data, and displays it on the TFT LCD screen. An alarm is triggered when there is an abnormality, and the abnormal data is stored in the data storage circuit EEPROM.

[0053] like Figure 9 As shown in (c), the LOW_IN2 pin of the vehicle speed circuit is connected to the ADC3 pin of the MCU control chip in the control circuit. Its core components mainly include diode 5D2 and transistor 5Q6, as well as voltage divider resistors and matching resistors. Diode 5D2 and transistor 5Q6 suppress electromagnetic interference, and voltage divider resistors and matching resistors adjust the signal level. The Hall sensor outputs a pulse signal proportional to the vehicle speed. After filtering and shaping, the signal is input to the timer pin (TIM5_CH4) of the MCU. The MCU calculates the real-time vehicle speed by capturing the pulse frequency.

[0054] like Figure 9 As shown in (d), the turn signal circuit includes a left turn signal circuit and a right turn signal circuit, as well as a position light signal circuit and a high beam signal circuit; one end of the left turn signal circuit is connected to an external left turn signal, and the other end LT_IN is connected to the MCU control chip; one end of the right turn signal circuit is connected to an external right turn signal, and the other end RT_IN is connected to the MCU control chip; one end of the position light signal circuit is connected to an external position light, and the other end CLL_IN is connected to the MCU control chip; one end of the high beam signal circuit is connected to an external high beam, and the other end HB_IN is connected to the MCU control chip.

[0055] The above signal light circuit connections are similar. Taking the left turn signal circuit as an example, its core components are mainly resistors and capacitors. Resistors 5R1-5R4 are used for signal voltage division and current limiting, reducing the vehicle's high-level signal (such as 12V) to a logic level acceptable to the MCU (3.3V). The capacitors act as filters. The GRD ground pin provides a signal reference ground to ensure level stability. When the vehicle's left turn signal is activated, the high-level signal (such as 12V) is reduced to below 3.3V through the voltage divider resistor network. The divided signal is input to the MCU's ADC12 pin (PBC2). After the MCU detects the high level, it controls the screen to display the left turn icon. The multi-stage resistor design here can enhance anti-interference capability and prevent false triggering.

[0056] This utility model's TFT LCD bicycle instrument panel supports a wide voltage input power supply, including 48V lithium battery systems. In addition to displaying vehicle information such as cumulative mileage, battery level, and speed, the instrument panel also features data storage capabilities, allowing users to view current and historical records of abnormal driving events. This is particularly convenient for electric bicycle users facing challenging environments. When riding on bumpy roads or mountainous terrain, if the vehicle exhibits abnormal behavior, the instrument panel allows users to observe its operating status and identify and prevent potential malfunctions. Furthermore, the instrument panel is not easily affected by ambient light, enhancing its practicality and versatility.

[0057] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. It should be noted that for those skilled in the art, any changes or substitutions that can be easily conceived without departing from the technical principle of the present invention should be included within the protection scope of the present utility model.

Claims

1. A TFT LCD screen bicycle instrument panel, characterized in that, The device includes a housing and a TFT LCD screen mounted on the housing. The housing contains a control circuit and a data storage circuit. The control circuit has an MCU control chip. The data storage circuit is connected to the MCU control chip. The control circuit is connected to a power-on / off detection circuit and a data processing circuit. The power-on / off detection circuit is connected to a power management circuit. The data processing circuit transmits data to the display circuit via a CAN circuit.

2. The TFT LCD screen bicycle instrument according to claim 1, characterized in that, The data storage circuit is connected to the control circuit and includes an EEPROM memory chip. On one end, all three device address configuration pins and the ground pin are grounded. On the other end, the SCL pin and SDA pin are connected to the MCU control chip via an I2C bus. The I2C bus is equipped with pull-up resistors R22 and R23. The VCC1 pin is connected to power supply filter capacitors C21 and C22. The write protection pin WP is connected to a low level to enable writing.

3. The TFT LCD screen bicycle instrument according to claim 1, characterized in that, The power-on / off detection circuit is connected to the power management circuit and includes vehicle ignition signal input and signal output pins. A voltage divider resistor and a pull-down resistor are provided between the vehicle ignition signal input and signal output pin circuits. The voltage divider resistors 2R1 and 2R3 reduce the high-level signal to a logic level acceptable to the MCU control chip, and the pull-down resistor 2R2 ensures that the output pin remains at a low level when there is no signal input.

4. A TFT LCD screen bicycle instrument according to claim 1 or 3, characterized in that, The power management circuit has an input voltage range of 8~60V, which is stepped down to 3.3V by a DC-DC converter circuit to power the MCU control chip and TFT LCD screen.

5. A TFT LCD screen bicycle instrument according to claim 4, characterized in that, The power management circuit specifically includes a feedback network and an LDO regulator. The feedback network sets the output voltage through voltage divider resistors 1R4 and 1R5, and the LDO regulator steps it down to 3.3V. The DC-DC conversion circuit connects an EMI suppression circuit and a filter circuit. The filter circuit consists of multiple capacitors connected in parallel. The EMI suppression circuit includes TVS diodes TVS1 and TVS3 connected in parallel at the input stage to suppress surge voltage, and an LC filter network 1L1 and 1C6 to filter out high-frequency noise.

6. A TFT LCD screen bicycle instrument according to claim 1, characterized in that, The data processing circuit includes a tire pressure module circuit and a vehicle speed circuit, as well as an ambient light detection circuit and a turn signal circuit. The tire pressure module circuit includes an SPI FLASH chip, which communicates with the MCU control chip via an SPI interface, and stores abnormal data in the data storage circuit EEPROM. The vehicle speed circuit is connected to the control circuit and includes diodes and transistors, as well as voltage divider resistors and matching resistors. The diodes 5D2 and 5Q6 suppress electromagnetic interference, and the voltage divider resistors and matching resistors adjust the signal level. The ambient light detection circuit is connected to the MCU control chip via a ZM_IN interface and includes a photosensor and a resistor-capacitor combination. The photosensor changes its resistance value according to the light intensity, the resistor converts the photosensor's resistance value into a voltage signal, and the capacitor is a filter capacitor. The turn signal circuit includes a left turn signal circuit and a right turn signal circuit, as well as a position light signal circuit and a high beam signal circuit.

7. A TFT LCD screen bicycle instrument according to claim 6, characterized in that, One end of the left turn signal circuit is connected to the external left turn signal, and the other end is connected to the MCU control chip; one end of the right turn signal circuit is connected to the external right turn signal, and the other end is connected to the MCU control chip; one end of the position light signal circuit is connected to the external position light, and the other end is connected to the MCU control chip; one end of the high beam signal circuit is connected to the external high beam, and the other end is connected to the MCU control chip.

8. A TFT LCD screen bicycle instrument according to claim 1, characterized in that, The CAN circuit is connected to the control circuit. The CAN transceiver chip converts the TTL level signal of the MCU control chip into a differential signal of the CAN bus. Specifically, it includes a CAN transceiver chip and a TVS diode. The CAN transceiver chip processes the MCU control chip level signal after it has been filtered by a filter capacitor. The TVS diode is connected to the CAN bus terminating resistor and the filter capacitor. A common-mode inductor L8 is provided in the middle to suppress bus noise.

9. A TFT LCD screen bicycle instrument according to claim 1, characterized in that, The display circuit includes a TFT LCD screen display circuit and a backlight power supply. The TFT LCD screen display circuit mainly includes an LCD module and multiple RN connection circuits, wherein the LCD module is connected to the MCU control chip and the multiple RN connection circuits; one end of the backlight power supply is connected to the TFT LCD screen display circuit, and the other end is connected to the control circuit.

10. A TFT LCD screen bicycle instrument according to claim 9, characterized in that, The backlight power supply includes a MOSFET 4Q1 and a transistor 4VT1. The input PWM signal is provided by the MCU control chip. The MOSFET 4Q1 controls the LED backlight on / off and brightness through the PWM signal. The transistor assists in current regulation. The backlight power supply also includes a filter capacitor to smooth the PWM signal and suppress noise.

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