CN2809777Y - Display circuit for motor vehicle gauge - Google Patents

Abstract

The utility model relates to a display circuit for a motor vehicle gauge, which discloses a circuit on a vehicle meter for displaying data parameters. The utility model overcomes the defect that the traditional interface mode adopted by the modern multiple gauge system has high cost and low working reliability by serially transmitting data to all shift registers. The utility model is composed of a central processing unit 1, multiple digital cord strips or an eight-section LED display 2, and multiple shift registers 3, wherein the shift registers 3 are connected together in series. An output end Q of the shift register 3 positioned on the front end is connected with an input end D of the shift register 3 adjacent to the output end Q and positioned behind the output end Q and the data input of a digital cord strip or the eight-section LED display 2. The data output end RXD of the 1 is connected with the input end D of the 3 positioned on the front end, and the zero clearing signal output ends CLR of the 1 are respectively connected with the resetting end R of each shift register 3. The clock signal output ends CLK of the 1 are respectively connected with the clock signal input end CP of each 3.

Description

The display circuit of vehicle meter

Technical field:

The utility model relates to the circuit that is used for the video data parameter on a kind of vehicle meter.

Background technology:

At present, the most of instrument that shown by electronics of the pointer instrument on the motor vehicle replace.Owing to the automobile each side parameter and the data that need in the modern intelligent automobile to monitor are many, thereby the instrument number on the panel board is many, because having, luminous bar code shows advantage and the display effect that approaches traditional pointer more intuitively in addition, be subjected to liking of driver deeply, so eight of luminous bar code and display digit sections light-emitting diode displays use simultaneously on the panel board of some automobile, the result who does has like this strengthened the quantity of display unit and the quantity of interface chip undoubtedly.Though adopt traditional parallel interface mode control strategy fairly simple, because the I/O mouth of common central processing unit is limited, want to control all display units, must increase decoding scheme or select expensive processor for use.Increasing of display unit also can make the wiring of interface circuits such as register many in addition, and the reliability of work is reduced, and increased the cost of product.Therefore on the motor vehicle of many instrument systems in modern times, adopt the reliability of traditional display circuit interface mode cost height, work low.

The utility model content:

The purpose of this utility model provides a kind of display circuit of vehicle meter, adopts traditional display circuit interface mode circuit cost height, the low defective of reliability of work to overcome on the motor vehicle of many instrument systems in modern times.It is by central processing unit 1, n number code-bar or eight sections light-emitting diode displays 2 and n shift register 3 are formed, n shift register 3 is cascaded, the output terminal Q that is positioned at the shift register 3 of front end connects the input end D of the shift register that is positioned at its rear end 3 that is adjacent and the data input pin of a number code-bar or eight sections light-emitting diode displays 2, the data output end RXD of central processing unit 1 connects the input end D of the shift register 3 that is positioned at head end, the reset signal output terminal CLR of central processing unit 1 connects the reset terminal R of each shift register 3 respectively, and the clock signal output terminal CLK of central processing unit 1 connects the clock signal input terminal CP of each shift register 3 respectively.When display circuit of the present utility model is worked, central processing unit 1 is pressed shift register 3 to the data of each sensor acquisition on the motor vehicle and is connected the order serial transfer in each shift register 3, be connected the digital bar of shift register 3 output terminals or eight sections light-emitting diode displays 2 according to the binary number of shift register 3 outputs corresponding with it according to the show digital bar the light and shade ratio or show shinny stroke section.Because n shift register 3 be cascaded, so data delivery outlet of 1 needs of central processing unit provide digital just can for all display units, selects for use common central processing unit 1 competent at a job with regard to energy.All in addition shift registers 3 are connected in series, and wiring is few, are not easy to be out of order, although a lot of instrument are arranged on the panel board, just can finish the real-time demonstration of all data and information by the continuous refresh operation of the control of clock.The utlity model has simple in structure, reliable operation, be easy to the advantage of promotion and implementation.

Description of drawings:

Fig. 1 is a structural representation of the present utility model, and Fig. 2 is the electrical block diagram of embodiment two.

Embodiment:

Embodiment one: specify present embodiment below in conjunction with Fig. 1.Present embodiment is by central processing unit 1, n number code-bar or eight sections light-emitting diode displays 2 and n shift register 3 are formed, n shift register 3 is cascaded, the output terminal Q that is positioned at the shift register 3 of front end connects the input end D of the shift register that is positioned at its rear end 3 that is adjacent and the data input pin of a number code-bar or eight sections light-emitting diode displays 2, the data output end RXD of central processing unit 1 connects the input end D of the shift register 3 that is positioned at head end, the reset signal output terminal CLR of central processing unit 1 connects the reset terminal R of each shift register 3 respectively, and the clock signal output terminal CLK of central processing unit 1 connects the clock signal input terminal CP of each shift register 3 respectively.

Embodiment two: specify present embodiment below in conjunction with Fig. 2.The difference of present embodiment and embodiment one is: it is the chip of 74LS164 that shift register 3 is selected model for use, shared 20 shift registers 3 in the present embodiment, the i.e. first chip U1 to the, 20 chip U20, each digital bar is made up of ten light emitting diodes, shared eight number code-bars in the present embodiment, i.e. first digital bar U22A to the eight digital bar U22H, shared 12 eight sections light-emitting diode displays in the present embodiment, be ten No. two eight sections light-emitting diode display DS12 of eight sections light-emitting diode display DS1 to the of number one, the data output end RXD of central processing unit 1 connects the pin 1 of the first chip U1 and pin 2 to its Data transmission, the reset signal output terminal CLR of central processing unit 1 connects the pin 9 of the first chip U1 to the, 20 chip U20 respectively, the clock signal output terminal CLK of central processing unit 1 connects the pin 8 of the first chip U1 to the, 20 chip U20 respectively, the pin 3 of the first chip U1 is connected an end of first resistance R, 001 to the 8th resistance R 008 respectively to pin 6 and pin 10 to pin 13, the other end of first resistance R, 001 to the 8th resistance R 008 connects the pin 1 of the first digital bar U22A respectively, pin 3, pin 5, pin 7, pin 9, pin 11, pin 13 and pin 15, the pin 2 of the first digital bar U22A, pin 4, pin 6, pin 8, pin 10, pin 12, pin 14 and pin 16 all are connected on the power supply VCC, the pin 13 of the first chip U1 connects pin 1 and the pin 2 of the second chip U2, other shift register, the connected mode of digital bar or eight sections light-emitting diode displays is identical with the connected mode of the first digital bar U22A with the first chip U1.The 74LS164 chip is to go here and there to change shift register in the lump, selects for use this chip price cheap, and a chip can be controlled eight light emitting diodes.

Claims (2)

1, the display circuit of vehicle meter, it is characterized in that it is by central processing unit (1), n number code-bar or eight sections light-emitting diode displays (2) and n shift register (3) are formed, n shift register (3) is cascaded, the output terminal (Q) that is positioned at the shift register (3) of front end connects the input end (D) of the shift register that is positioned at its rear end (3) that is adjacent and the data input pin of a number code-bar or eight sections light-emitting diode displays (2), the data output end (RXD) of central processing unit (1) connects the input end (D) of the shift register (3) that is positioned at head end, the reset signal output terminal (CLR) of central processing unit (1) connects the reset terminal (R) of each shift register (3) respectively, and the clock signal output terminal (CLK) of central processing unit (1) connects the clock signal input terminal (CP) of each shift register (3) respectively.

2, the display circuit of vehicle meter according to claim 1, it is characterized in that it is that first chip (U1) of 74LS164 is to the 20 chip (U20) that shift register (3) is selected model for use, the first digital bar (U22A) to the 8th digital bar (U22H) is made up of ten light emitting diodes respectively, the pin 1 of data output end (RXD) connection first chip (U1) of central processing unit (1) and pin 2 are to its Data transmission, the reset signal output terminal (CLR) of central processing unit (1) connects the pin 9 of first chip (U1) to the 20 chip (U20) respectively, the clock signal output terminal (CLK) of central processing unit (1) connects the pin 8 of first chip (U1) to the 20 chip (U20) respectively, the pin 3 of first chip (U1) to pin 6 and pin 10 to pin 13 is connected the end of first resistance (R001) to the 8th resistance (R008) respectively, first resistance (R001) connects the pin 1 of the first digital bar (U22A) respectively to the other end of the 8th resistance (R008), pin 3, pin 5, pin 7, pin 9, pin 11, pin 13 and pin 15, the pin 2 of the first digital bar (U22A), pin 4, pin 6, pin 8, pin 10, pin 12, pin 14 and pin 16 all are connected on the power supply (VCC), and the pin 13 of first chip (U1) connects the pin 1 and the pin 2 of second chip (U2).

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