JPH0119152B2 - - Google Patents

Description

[Detailed description of the invention]

[Summary] The number display segment and the character display segment share terminals to reduce the number of control terminals, thereby achieving miniaturization and simplifying the control circuit. [Industrial Application Field] The present invention relates to a display device, and particularly to a display device that displays numerical information and character information. [Prior Art] Generally, in a digital watch, for example, a digital wristwatch, numbers from 0 to 9 are displayed in a plurality of segments, for example, seven segments. This is extremely widely applied, and is also used, for example, in display panels for car radios. Within this display panel, various numbers are displayed in seven segments. The first is the band information number, and the receiving frequency is, for example,
Displayed as AM1008kHz, FM86.5MHz. The second is clock information, where the numbers indicating the time are e.g.
Displayed as 6:07 AM and 8:09 PM. These numbers 0 to 9 are displayed on an LED display, a fluorescent tube display, or a liquid crystal display by driving any segment within the seven segments. [Problem to be solved by the invention] By the way, in the display panel, not only the numbers 0 to 9 but also AM, FM, kHz, MHz, AM,
Text information such as PM is displayed, and text information such as LW (long wave), MW (medium wave), STEREO, etc. may also be displayed. For this reason, when a display panel drive circuit is integrated into an IC (integrated circuit), the number of pins occupied for displaying this character information is not small among the limited number of pins on the IC. This was a hindrance to fully utilizing the functions. or,
For displaying these character information, the numbers (0
~9) Since a control circuit completely separate from the information control circuit had to be provided, there were various problems such as increased manufacturing wiring work and increased costs. [Means for Solving the Problems] The present invention aims to solve the above-mentioned problems, and provides numerical information representing a numerical value by changing a display pattern according to a display signal from a display signal source; In a display device that displays character information that is paired with information to represent the meaning of the numerical information or represents the content of a specific state by itself, the display device is composed of a plurality of numerical display segments, and the plurality of numerical display segments are selected. a group of numeric display segments that display numbers by a combination of the driven numeric display segments, the number display segment selection drive individual terminal provided individually for each of the numeric display segments; The terminal has a numeric display segment common terminal that is paired with the display segment selection drive individual terminal and is common to each of the numeric display segments, and when a drive signal is input to the numeric display segment common terminal, the numeric display segment The numeric display segments are selectively driven by selectively inputting a segment selection drive signal to the display segment selection drive individual terminal, and the numeric information is displayed at the timing when the drive signal is input to the numeric display segment common terminal. a group of numeric display segments that display a number display segment, and one or more character display segments that each display the character information by the segment shape itself, each character display segment being selected from the number display segment assigned in advance. It has an individual character display segment selection driving terminal that shares the individual driving terminal, and a character display segment common terminal that is a terminal that is paired with the character display segment selection driving individual terminal and that is common to each of the character display segments. By selectively inputting the segment selection drive signal to the individual terminal for numeric display segment selection drive while the drive signal is input to the character display segment common terminal,
The segment selection drive signal is inputted to the character display segment selection drive individual terminal that shares the numeric display segment selection drive individual terminal to selectively drive the character display segment, and the character display segment common terminal is input to the character display segment selection drive signal. The drive signal is sequentially applied to the character display segment group that displays the character information at the timing when the drive signal is input, the number display segment common terminal of the number display segment group, and the character display segment common terminal of the character display segment group. a timing setting circuit that receives the drive signal from the timing setting circuit and selectively drives the numeric display segment selection according to the display signal from the display signal source at the timing when the drive signal is output. and a selection drive circuit that outputs the segment selection drive signal to the individual terminals for the segment selection drive signal. [Example] The present invention will be described below with reference to the drawings. 1A and 1B are block diagrams schematically illustrating a conventional apparatus for digital display and an apparatus of the present invention, respectively. In both figures, 11 is
A character information display section 12 is composed of a group of character display segments such as AM, PM, FM, etc., a numeric information display section 12 is a numeric information display section consisting of a group of numeric display segments 0 to 9, and 13 is a control circuit for the numeric information display section 12. Conventionally, the first
As shown in Figure A, an independent control circuit 14 was required for the character information display section 11. For this reason, for driving the display panel 10 (consisting of 11 and 12)
In IC15, the proportion of pins occupied for displaying character information among the number of pins was quite high. Therefore, there was a problem in that the functions that should be provided to the IC15 were reduced in order to display characters. Furthermore, since the control circuit 14 for character display is required independently, wiring work during manufacturing increases. On the other hand, according to the device of the present invention shown in FIG. 1B,
The conventional character display control circuit 14 is no longer necessary,
Among the pins of the IC15, the pins conventionally occupied for displaying characters can now be used for other purposes, and the functions of the IC15 can be greatly expanded. Furthermore, since the control circuit 14 for character display is no longer required, the wiring work during manufacturing is reduced accordingly, leading to lower costs. However, a dynamic drive section 16 is separately required to drive the character information display section 11 and the numerical information display section 12 alternately at respective timings. However, since the dynamic drive unit 16 can be constructed simply by having a counter, there is hardly any problem in terms of hardware. FIG. 2 is a diagram for clearly explaining the operating principle of the block structure according to the present invention shown in FIG. 1B. In this figure, character display segment group 2
1 corresponds to the character information (for example, W, X, Y, Z) display section 11 shown in FIGS. 1A and 1B, and the numeric display segment group 22 corresponds to the numeric information (0 to 9) display section 12 shown in the same figure. . The number display segment group 22 consists of a plurality of segments, usually seven segments a, b...g, and as is well known, for example, for the number "3", segments a, b, c, d and g are driven. Conventionally, these seven segments are numbers (0 to
9) was used only to form and display.
However, in the present invention, these seven segments are commonly used not only for displaying numerical information but also for displaying character information (W to Z). For example, the letter "W" is assigned to the a segment, and the letters "X", "Y", and "Z" are assigned to the f, e, and d segments, respectively. Therefore, for example, in order to display the character "X", it is sufficient to specify the ff segment previously allocated to it. Note that each of the letters "W to Z" is displayed by a single display element, for example, an LED, a fluorescent tube, a liquid crystal, or the like. In the example in this figure, up to seven types of character information can be assigned to each of the seven segments, but if necessary, even more types of character information can be specified by combining two or more segments. You can also do it. By the way, in Fig. 2, for example, the character "X",
If “Y” is specified, the f segment and e segment will be specified, so in addition to “X” and “Y” as characters, “1” as a number
will also be displayed at the same time. However, since this number "1" is a meaningless display, it is necessary to mask it. Therefore, the present invention applies a well-known dynamic drive. For example, if the information to be displayed is the letter "Z" and the number "6", the d segment for displaying the letter "Z" is driven at the timing shown in the lower part of Figure 2, and at the timing Drive the a, f, e, d, c, and g segments to display the number "6". Since only the character display segment group 21 is activated during timing, and only the number display segment group 22 is active during timing, the character "Z" and the number "6" are dynamically alternately displayed. will be displayed in segment groups 21 and 22 of.
Therefore, if the timing of this dynamic drive is set to a high frequency, the human eye will see the letter "Z".
and the number "6" appear to be lit simultaneously in the character display segment group 21 and the number display segment group 22. The timing of these dynamic drives can be set, for example, by a counter (dynamic drive unit 16 in FIG. 1B). In this way, a digital display device is realized that is free from the problems mentioned above. FIG. 3 is a circuit configuration diagram showing an example in which the digital display device of the present invention explained in FIGS. 1B and 2 is applied to a display panel of a vehicle-mounted radio receiver. In this figure, 11 is AM, PM, LW, MW,
12 is a character information display section consisting of the aforementioned character display segment group that displays characters such as FM, STEREO, etc. 12 is the aforementioned numerical information display section that displays a pattern such as the number 1888 (however, in this figure, it is a 4-block segment) consisting of a group). Note that the most significant digit only has a 1, so it does not have a 7-segment configuration. These segment groups are commonly connected to each other, and the segment group connected to individual terminal a (corresponding to segment a in Fig. 2) has character information “LW”, and similarly the individual terminals b and c , d, e, and f (corresponding to segments b to f in Figure 2) contain character information such as "MW", "AM", "FM",
“STEREO” and “PM” are respectively assigned. However, these allocation methods may be arbitrary. These segment groups have individual terminals a, b...
g (a segment selection drive signal for displaying data points is input to the individual terminal DP),
The segment selection drive signal is applied from a PLA (programmable logic array) circuit 33 via a drive circuit D2. The two drive circuits D1 and D2 in the figure are necessary only for fluorescent tube display, and the same applies to the heater H. This is because LED displays and liquid crystal displays can be driven directly by logic signal levels. In addition, the dashed-dotted line 31 in the figure shows the boundary of the driving area of the display panel, and the dashed-dotted line 32 shows the boundary of the area of the IC 15 shown in FIG. 1B. Further, L is a common power supply line in the case of a fluorescent tube display. Also G1, G2, G
3, G4 and G5 are common terminals. The arrangement in the upper part in FIG. 2 is thus realized. Next, the configuration for implementing the dynamic drive shown in the lower part of FIG. A display signal from a display signal source according to the timing signal.
A selection drive circuit is required that selectively inputs FD, CD, and TD and selectively outputs segment selection drive signals to the individual terminals a, b...g, DP in accordance with the display signals. This timing setting circuit 35 is a dynamic drive section 16 (counter) in FIG. 1B.
The selection drive circuit is realized by the data selector 34, the PLA circuit 33, etc. The timing setting circuit (counter) 35 connects the common terminals G1, G2, G3,
For G4 and G5, sequentially phase-shifted drive signals, that is, timing signals T1, T2, T
3, T4 and T5 are applied respectively. These timing signals are generated by clock pulses CL. When the timing signal T1 is output, a segment selection drive signal forming the first digit of the numerical information is given from the PLA circuit 33, and similarly, when the timing signals T2, T3 and T4 are output, the segment selection drive signal forming the first digit of the numerical information is applied to the numerical information 2, 3 and 4, respectively. The segment selection drive signal forming the digit number is transmitted to the PLA circuit 33.
given sequentially. When the timing signal T5 is output, character information (AM, PM, etc.) is formed, and which character is formed is designated by the segment selection drive signal, as described above. These 1~
The timing for specifying the fourth digit number and character is defined by the timing signals T1 to T5 applied to the data selector 34. The data selector 34 receives the clock/frequency switching signal T/F, and when it is a clock (T), gives the clock information data TD to the PLA circuit 33 as numeric information, and when it is a frequency (F), it gives the clock information data TD as character information. The received frequency information data FD is given to the PLA circuit 33. The switching signal T/F is manually set according to the operator's wishes. Also, regarding these data TD and FD,
It is provided by a PLL (phase locked loop) circuit (not shown). The PLL circuit is a common component in modern frequency synthesizer type digital radio receivers, and therefore the PLL circuit is used for the data TD,
It is not necessary to introduce any special means to obtain FD. This PLL circuit can also output character information data CD. The PLA circuit 33 basically functions as a decoder, and receives frequency information data FD from the display signal source.
It receives clock information data TD and character information data CD, determines which segment is to be driven, and provides segment selection drive signals to be applied to the individual terminals DP, a, b...g. this
The PLA circuit 33 is, for example, an accumulator,
Although it consists of an AND matrix and an OR matrix, their details are omitted because they are not very important for explaining the idea of the present invention. However, only one example of the logical format of the resulting segment selection drive signal is listed in the table below. In the upper column of the table below, DP, a, b...g indicate the logic bits (1, 0) of the segment selection drive signal to be applied to the individual terminals DP, a, b...g, respectively, in FIG. The right column shows the pattern to be displayed (0, 1, 2...
9, A, b, C, d, E, 0., 1., 2., …9., suppress, LW, MW, FM, FM・ST
(STEREO), AM, PM). Suppress means no display.

【table】

〔Effect of the invention〕

As described in detail above, according to the present invention, in a display device that simultaneously displays character information and numerical information on the same panel, individual terminals for character display segments and numerical display segments are shared, thereby reducing the number of control terminals. Therefore, miniaturization and simplification of the control circuit can be achieved.

[Brief explanation of drawings]

1A and 1B are block diagrams schematically illustrating a conventional digital display device and a device according to the present invention, respectively, and FIG. 2 provides an easy-to-understand explanation of the operating principle of the block configuration according to the present invention shown in FIG. 1B. FIG. 3, which is a diagram for explanation, is a circuit configuration diagram showing an example of application of the digital display device of the present invention. In the figure, 11 is a character information display section, 12 is a numerical information display section, 13 is a control circuit, 15 is an IC circuit,
a, b...g, DP are individual terminals, G1, G2...G5
is a common terminal.

Claims (1)

[Claims] 1. Numerical information that represents a numerical value by changing the display pattern in accordance with a display signal from a display signal source, and that represents the meaning of the numerical information in pairs with the numerical information or alone. A display device that displays character information representing the contents of a specific state, which is composed of a plurality of number display segments, selectively drives the plurality of number display segments, and displays numbers by a combination of the driven number display segments. A group of numeric display segments for displaying a group of numeric display segments, comprising an individual terminal for numeric display segment selection drive provided individually in each of the numeric display segments, and a terminal paired with the individual terminal for numeric display segment selection drive, each of which is provided individually for each of the numeric display segments. The numeric display segment has a numeric display segment common terminal common to the numeric display segment, and a segment selection drive signal is selectively applied to the numeric display segment selection drive individual terminal in a state where a drive signal is input to the numeric display segment common terminal. a group of numeric display segments that selectively drive the numeric display segments in response to an input and display the numeric information at the timing when a drive signal is input to the common terminal of the numeric display segments; Therefore, the character display segment is composed of one or more character display segments for displaying the character information, and each character display segment has an individual terminal for character display segment selection driving that shares the previously allocated individual terminal for selecting and driving the number display segment. , a character display segment common terminal that is a terminal paired with the character display segment selection drive individual terminal and that is common to each of the character display segments, and the drive signal is input to the character display segment common terminal. By selectively inputting the segment selection drive signal to the individual terminal for numeric display segment selection drive in the state where
The segment selection drive signal is inputted to the character display segment selection drive individual terminal that shares the numeric display segment selection drive individual terminal to selectively drive the character display segment, and the character display segment common terminal is input to the character display segment selection drive signal. The drive signal is sequentially applied to the character display segment group that displays the character information at the timing when the drive signal is input, the number display segment common terminal of the number display segment group, and the character display segment common terminal of the character display segment group. a timing setting circuit that receives the drive signal from the timing setting circuit and selectively drives the numeric display segment selection according to the display signal from the display signal source at the timing when the drive signal is output. and a selection drive circuit that outputs the segment selection drive signal to individual terminals for the display.