JP2602284B2 - LCD time-sharing dynamic drive system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an LCD time-division dynamic drive system used as a display device such as an integrating calorimeter.

[Prior art] As a conventional LCD time-division dynamic drive system of this type, a segment is divided into several groups, and these are dynamically driven in a time-division manner for each group, thereby suppressing a decrease in contrast and displaying numbers. There is something that is made to do.

One example is a time-sharing dynamic drive system with 1/3 bias and 1/3 duty. However, in the standard number display system, three LCD terminals are required for each digit.

[Problems to be Solved by the Invention] In the conventional LCD time-division dynamic driving method, an LCD
, The circuit configuration becomes complicated, and it is difficult to increase the circuit density. In addition, it is necessary to increase the capacity (number of bits) of the microcomputer or the LCD register in the LCD driver corresponding to each digit of the LCD. However, when using a general-purpose low-cost microcomputer register, it is actually The capacity of the register cannot be so large.

An object of the present invention is to stably and reliably drive control an LCD in which a plurality of odd-numbered digit display elements composed of seven segments are arranged using a first line and a second line.
The number of terminals for driving the LCD can be reduced, the density of the drive circuit can be increased, the rational use of general-purpose LCDs can be rationalized, the capacity of the LCD register can be reduced, and the display software can be simplified. And to provide an LCD time-sharing dynamic drive system.

[Means for Solving the Problems] In order to solve the above problems and achieve the object, an LC of the present invention is used.
The D time-sharing dynamic drive system is configured as follows. That is, in a method of displaying an LCD in which a plurality of digits are arranged in a plurality of digits in a seven-segment shape of a day character by performing time-division dynamic driving with a 1 / m bias and a 1 / n duty, , Each segment of the 7 segments is a to f clockwise from the upper segment, and the central horizontal segment is g. When all segments are along the digit direction, “first digit baf” “second digit” a "and" the third digit baf "is 1
A column in which a plurality of patterns as patterns are sequentially and repeatedly provided from the lower digit to the upper digit, “cg of the first digit”, “bgf of the second digit”, “ge of the third digit”
A column in which a plurality of patterns are sequentially and repeatedly provided from the lower digit to the upper digit, “1st digit de”, “2nd digit cde”, “3rd digit cd” is 1
A plurality of patterns are sequentially arranged in order from a lower digit to an upper digit, and are divided into three columns of a first series, and an LCD in which the digit display elements are arranged in a plurality of digits is provided. From the lower digit to the upper digit, the three digits are divided into a plurality of blocks as one block, and the “first digit” “second digit” for each block
The segment group included in the “third digit” is divided into “first digit bcd” and “first digit age” along the direction orthogonal to the digit direction.
7 groups of "1st digit f and 2nd digit bc""2nd digit agd""2nd digit ef and 3rd digit b""3rd digit agc""3rd digit fed" One electrode of each segment is commonly connected to the common side terminal of the LCD for each column of the first series, and the other electrode of each segment is connected to each group of the second series. Commonly connected to the LCD segment side terminals, each bit output of a plurality of LCD registers for each digit having the same correspondence to each digit segment is given to the segment side terminal corresponding to each digit segment to be displayed At the same time, a signal of 1 / m bias and 1 / n duty generated based on each bit output of the LCD register is periodically supplied to each common terminal in a time division manner. [Action] As a result of taking the above-described means, the following action occurs. That is, in the present invention, the LCD is divided into three columns along the digit direction forming the first series while using an odd-numbered digit display element composed of seven segments, which is simply arranged in a plurality of digits. The number of segments in each column is the same when the number of display digits is a multiple of three digits, and is almost the same even with other numbers of digits, with only one difference. Further, the number of segments in each of the groups divided into a plurality of groups along the direction orthogonal to the digit direction forming the second series is exactly equal to three. For this reason, the first
Stable and reliable drive control can be performed using the common wiring of the series and the second series.

In addition, each bit of the LCD register for each digit and the 7 segments of each digit have the same correspondence. Therefore, each segment drive wiring of the LCD is shared to the maximum. Therefore, the number of terminals for driving the LCD can be reduced, the wiring between the terminals of the LCD and each bit in the LD register is simplified, and the circuit configuration is simplified. As a result, the density of the driving circuit is increased.

In addition, the LCD only needs to have a simple arrangement of a plurality of odd-numbered digit display elements consisting of 7 segments, and does not require any additional auxiliary electrodes. Therefore, the configuration of the LCD itself can be simple. It is not necessary to provide useless wiring. In other words, a general-purpose LCD can be used reasonably.

Further, since the capacity of the LCD register can be small, and the data to be loaded into the LCD register is common to all digits, it is preferable for forming a program, and the display software can be simplified.

[Embodiment] FIGS. 1 to 4 show an embodiment in which the present invention is applied to a 7-digit LCD display device for displaying a battery voltage and a measured temperature. In this example, 1/3 bias, 1
This is an example using a time-sharing dynamic drive method of / 3 duty.

FIG. 1 is a view showing a wiring relationship between segment side terminals S1 to S17 of the LCD and one (front side) electrode of the segment, and FIG. 2 is a diagram showing common side terminals C1 to C3 of the LCD and the other of the segments. It is a figure which shows the wiring relationship with the electrode of (back side).

A1 to A7 in FIG. 1 show one (front side) segment electrode group corresponding to the 7-digit display element.
B1 to B7 indicate the other (back side) segment electrode group corresponding to the seven-digit display element.

As shown in FIG. 3, each digit display element has seven a to g
Are arranged in the shape of a date, and are display elements composed of seven segments. These seven segments are defined clockwise from the upper piece as a to f, and the central horizontal piece as g. As is well known, each segment has a liquid crystal display element sandwiched between a pair of electrodes and emits light when two divided voltages are simultaneously applied to both electrodes. Can be demonstrated.

Returning to FIG. As shown in the drawing, the wiring for one of the segment electrode groups A1 to A3 and A4 to A6 has exactly the same wiring pattern. And the electrode groups A1 and A4, A2 and A5,
Each wiring for A3 and A6 also has the same wiring pattern. Note that the wiring for electrode group A7 is
The wiring pattern is the same as the wiring for A1 and A4. S1 to S17 are segment side terminals, except S17
S1 to S16 are all wired in common to three segment electrodes.

What is characteristic here is that the electrode corresponding to the sixth segment f of the electrode group A1 and the electrode corresponding to the second segment b of the electrode group A2 are connected by the wiring M at adjacent positions. It is a point. Similarly, an electrode corresponding to the sixth segment f of the electrode group A2 and a second segment b of the electrode group A3
Is connected to the corresponding electrode by the wiring N. The same applies between A4 and A5 and between A5 and A6.

On the other hand, as shown in FIG.
B3 and B4 to B6 have exactly the same wiring pattern. The wirings for the electrode groups B1 and B4, B2 and B5, and B3 and B6 also have the same wiring pattern.
The wiring for the electrode group B7 has the same wiring pattern as the wiring for B1 and B4. C1 to C3 are common-side terminals, which are connected to common wiring lines X, Y, and Z. The common wirings X, Y, and Z are obtained by dividing the segment electrode groups B1 to B7 into three systems along the digit direction, and providing a common wiring to each electrode of each system.

Note that the number of electrodes included in each series is the same when the number of display digits is a multiple of three digits, and is substantially the same even when the number of other digits is small, with only one difference. In the case of this embodiment, since the number of display digits is seven, 17 and 16 are used.
It is 16 pieces.

Thus, wiring is performed with a uniform, less wasteful and uniform wiring pattern.

FIG. 4 is a view showing the 7 digit display element of the LCD shown in FIG.
In segments a to g and microcomputer
FIG. 6 is a diagram showing a correspondence relationship with each of bits 0 to 6 of an LCD register.

As shown in the figure, bits 0 to 6 of the LCD register for each digit have the same correspondence with segments g to d of each digit. As described above, the output of each bit 0 to 6 in the plurality of LCD registers for each digit having the same correspondence with each digit segment g to d corresponds to the segment corresponding to each digit segment g to d to be displayed. Side terminals S1 to S17
1 / m bias, 1 / n, which is generated based on the output of each of bits 0 to 6 of the LCD register.
A duty signal is periodically given to each of the common terminals C1 to C3 by time division.

Hereinafter, the operation and operation of the present embodiment will be described. When data to be displayed on the LCD is input to an LCD register (not shown), this data is loaded for each bit as shown in FIG. 4 corresponding to the segment to be displayed. Then, a signal is transmitted to the first digit display element via the segment side terminals S1 to S3, and a signal is transmitted to the second digit display element via the segment side terminals S3 to S5. Is done. Similarly, for the third digit, terminals S5 to S7
Signal is sent out through the terminals S7 to S4 for the fourth digit.
A signal is sent out via S9, and for the fifth digit, the terminal S9
A signal is transmitted via terminals S11 to S13, a signal is transmitted via terminals S11 to S13 for the sixth digit, and a signal is transmitted via terminals S13 to S15 for the seventh digit. . Also, for each digit common wiring X, Y, Z, signals are output in a cyclic manner in the order of C1 to C2 to C3 to C1 through the common side terminals C1, C2, C3 in a time-division manner. . The following table shows the LCD register bits,
It is a table | surface which shows the correspondence of a common side terminal, a segment side terminal, and a display segment.

・ First digit display element When the common side terminal C1 is “1”, the segments f, a, b
Becomes a displayable state. When the segment f is displayed, the segment side terminal S3 is set to "1". When the segment a is displayed, the segment side terminal S2 is set to "1".
When displaying the segment b, the segment side terminal S1 is set to "1".

When the common terminal C2 is "1", the segments g and c are in a displayable state. When displaying the segment g, the segment side terminal S2 is set to "1", and when displaying the segment c, the segment side terminal S1 is set to "1".

When the common terminal C3 is "1", the segments e and d are in a displayable state. To display the segment e, the segment side terminal S2 is set to "1" and the segment d
Is displayed, the segment side terminal S1 is set to "1".

-Second digit display element When the common-side terminal C1 is "1", the segment a can be displayed. When displaying segment a, the segment side terminal S4 is set to "1".

When the common side terminal C2 is "1", the segments g, f, b
Becomes a displayable state. When the segment g is displayed, the segment side terminal S4 is set to "1". When the segment f is displayed, the segment side terminal S5 is set to "1".
When displaying the segment b, the segment side terminal S3 is set to "1".

When the common terminal C3 is "1", the segments e, c, d
Becomes a displayable state. When the segment e is displayed, the segment side terminal S5 is set to "1". When the segment c is displayed, the segment side terminal S3 is set to "1".
To display the segment d, the segment side terminal S4 is set to "1".

• Third digit display element When the common side terminal C1 is "1", the segments f, a, b
Becomes a displayable state. When the segment f is displayed, the segment side terminal S7 is set to "1". When the segment a is displayed, the segment side terminal S6 is set to "1".
When displaying the segment b, the segment side terminal S5 is set to "1".

When the common terminal C2 is "1", the segments g and e are in a displayable state. To display the segment g, the segment side terminal S6 is set to "1" and the segment e
Is displayed, the segment side terminal S7 is set to "1".

When the common terminal C3 is "1", the segments c and d are in a displayable state. To display the segment c, the segment side terminal S6 is set to “1”, and the segment d is set.
Is displayed, the segment side terminal S7 is set to "1".

The above-mentioned signal to the LCD is a signal sent to the first digit display element to the third digit display element, but the segment signal for displaying the fourth digit display element to the sixth digit display element is the same as that of S1 described above. S8, S2 S9, S3 S10, S4 S11, S5 S12, S6 S1
3, S7 should be read as S14. For the segment signal for displaying the display elements after the seventh digit display element,
The same reading as described above may be performed.

(Summary of Embodiment) The configuration and operation of the LCD time-division dynamic drive system shown in the above embodiment are summarized as follows.

In a method of displaying an LCD in which a plurality of digit display elements consisting of 7 segments of a day character are arranged in a plurality of digits by performing time-sharing dynamic driving with a 1 / m bias and a 1 / n duty, the day character is formed. When each piece of the segment is a to f clockwise from the upper piece and the center horizontal piece is g, all the segments along the digit direction are "first digit baf""second digit a"" 3rd digit baf is 1
A column in which a plurality of patterns as patterns are sequentially and repeatedly provided from the lower digit to the upper digit, “cg of the first digit”, “bgf of the second digit”, “ge of the third digit”
A column in which a plurality of patterns as patterns are repeatedly arranged in order from the lower digit to the upper digit, “1st digit de”, “2nd digit cde”, “3rd digit cd” is 1
A plurality of patterns are sequentially arranged in order from a lower digit to an upper digit, and are divided into three columns of a first series, and an LCD in which the digit display elements are arranged in a plurality of digits is provided. From the lower digit to the upper digit, the three digits are divided into a plurality of blocks as one block, and the “first digit” “second digit” for each block
The segment group included in the “third digit” is divided into “first digit bcd” and “first digit age” along the direction orthogonal to the digit direction.
7 groups of "1st digit f and 2nd digit bc""2nd digit agd""2nd digit ef and 3rd digit b""3rd digit agc""3rd digit fed" And one electrode of each segment is commonly connected to the common side terminals C1 to C3 of the LCD for each column of the first system, and the other electrode of each segment a to f is connected to the second system. A plurality of LCs for each digit, which are commonly connected to the segment side terminals S1 to S17 of the LCD for each group and have the same correspondence to the digit segments a to f.
Each bit output of the D register is provided to the segment side terminals S1 to S17 corresponding to each digit segment to be displayed, and 1 / m bias, 1 / m is created based on each bit output of the LCD register. An n-duty signal is periodically supplied to each of the common terminals in a time-division manner.

In the above LCD time division dynamic drive system,
The following effects occur. That is, while using an LCD in which odd-numbered digit display elements consisting of 7 segments are simply arranged in a plurality of digits, each of the columns divided into three columns along the digit direction constituting the first digit series is used. Are the same when the number of display digits is a multiple of three digits, and are almost the same even when the number of other digits is used, with only one difference being generated. Further, the number of segments in each of the groups divided into a plurality of groups along the direction orthogonal to the digit direction forming the second series is exactly equal to three. Therefore, stable and reliable drive control can be performed by using the first and second common lines provided so as to cross each other.

In addition, each bit of the LCD register for each digit and the 7 segments of each digit have the same correspondence. Therefore, each segment drive wiring of the LCD is shared to the maximum. Therefore, the number of terminals for driving the LCD can be reduced, the wiring between the terminals of the LCD and each bit in the LCD register can be simplified, and the circuit configuration can be simplified. As a result, the density of the driving circuit is increased.

In addition, as for the LCD, it is only necessary to arrange an odd-numbered digit display element composed of 7 segments in a plurality of digits, and since there is no need to provide any other auxiliary electrodes, the configuration of the LCD itself may be simple. It is not necessary to provide useless wiring. In other words, a general-purpose LCD can be used reasonably.

Further, since the capacity of the LCD register can be small, and the data to be loaded into the LCD register is common to all digits, it is preferable for forming a program, and the display software can be simplified.

It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the spirit of the present invention.

[Effects of the Invention] According to the present invention, it is possible to stably and reliably drive control an LCD in which a plurality of odd-numbered digit display elements composed of seven segments are arranged using a first line and a second line.
The number of terminals for driving the LCD can be reduced, the density of the drive circuit can be increased, the rational use of general-purpose LCDs can be rationalized, the capacity of the LCD register can be reduced, and the display software can be simplified. , An LCD time-sharing dynamic drive system can be provided.

[Brief description of the drawings]

1 to 4 are views showing an embodiment of the present invention. FIG. 1 is a view showing a wiring relationship between a segment side terminal of an LCD and one electrode of a segment, and FIG. 2 is a common side terminal. FIG. 3 is a diagram showing a wiring relationship between the second segment electrode and the other segment electrode, FIG. 3 is a diagram showing a configuration of a digit display element composed of seven segments, and FIG.
FIG. 6 is a diagram illustrating a correspondence relationship between an LCD register and a segment of a digit display element. A1 to A7, B1 to B7 ... Segment electrodes M, N ... Wiring X, Y, Z ... Common wiring S1 to S17 ... Segment side terminals, C1 to C3 ... Common side terminals, a to f ... segment

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-58-172683 (JP, A) JP-A-52-90295 (JP, A) JP-A-56-40889 (JP, A) 141071 (JP, U)

Claims (1)

(57) [Claims] 1. A system for displaying an LCD comprising a plurality of digit display elements consisting of seven segments of a day character by performing time-sharing dynamic driving with a 1 / m bias and a 1 / n duty. When 7 pieces of the 7-segment forming the shape of the letter are a to f clockwise from the upper piece and the horizontal piece at the center is g, all the segments along the digit direction are "first digit baf""twodigits" A column in which a plurality of patterns each having one pattern of “a” of “third digit” and “baf of third digit” are sequentially and repeatedly provided from the lower digit to the upper digit, “cg of first digit”, “bgf of second digit” A column in which a plurality of patterns having "ge of the third digit" as one pattern are sequentially and repeatedly provided from the lower digit to the upper digit, "de of the first digit", "cde of the second digit", "3" A plurality of patterns with “cd of the digit” as one pattern were sequentially and repeatedly provided from the lower digit to the upper digit. In addition to dividing the LCD into a first series by dividing the column into three columns, the LCD in which the digit display elements are arranged in a plurality of digits is divided into a plurality of blocks by dividing the three digits into one block from the lower digit to the upper digit, "1st digit""2nddigit""3" for each block
A group of segments included in the “digit” is divided into “bcd of the first digit”, “age of the first digit”, “1”
Digit f and second digit bc, second digit agd, second digit ef
And the third digit b, the third digit agc, and the third digit fed are divided into seven groups to form a second series. One electrode of each segment is provided for each column of the first series.
Commonly connected to the common side terminal of the LCD, the other electrode of each segment is commonly connected to the segment side terminal of the LCD for each group of the second series, and a plurality of digits for each digit having the same correspondence to each digit segment Each bit output of the LCD register is provided to the segment side terminal corresponding to each digit segment to be displayed, and 1 / m bias and 1 / n duty generated based on each bit output of the LCD register are provided. The time-sharing dynamic driving method of the LCD, characterized in that the above-mentioned signal is periodically given to each of the common side terminals in a time-sharing manner.