JPS64871B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a panel type television receiver equipped with a liquid crystal display panel.

[Prior art and its problems] In recent years, research has been carried out on pocketable television receivers using liquid crystal display panels. The liquid crystal display panel used in this type of panel-type pocket television receiver has scanning electrodes and signal electrodes arranged in a matrix, and has an LSI for driving the scanning electrodes and an LSI for driving the signal electrodes in the main body. ing.
The liquid crystal display panel is then driven by a drive method such as a known voltage averaging method. and,
The scanning electrode driving LSI operates periodically under timing control, and the signal electrode driving LSI is supplied with a digitized video signal and operates in accordance with the video signal.

Therefore, a liquid crystal display panel used in a portable television receiver has a large number of display dots, for example, 60×320 dots. Therefore, the signal electrode driving LSI must drive as many as 320 signal electrodes, so it must be divided into multiple parts, for example 4
The LSI is configured to drive 80 signal electrodes at a time. On the other hand, since the number of scanning electrodes is smaller than the number of signal electrodes and the operating frequency is lower, the LSI for scanning electrode driving is configured with one piece and has a built-in timing control circuit etc. to send timing control signals to drive each signal electrode.
It is conceivable to configure it so that it is distributed and supplied to the LSI. In such a portable television receiver, signal lines for various timing control signals are wired from the scanning electrode driving LSI to each signal electrode driving LSI, and the video signal lines supplied from the A/D converter are wired. There was a problem in that the wiring became extremely complicated because the signal lines were wired to each signal electrode driving LSI.

This invention was made in view of the above circumstances,
The video signal supplied from the A/D converter is once received by one scanning electrode driving LSI, and then distributed and supplied together with various timing signals to multiple signal electrode driving LSIs, simplifying circuit wiring. The purpose is to

[Means for Solving the Problems] The present invention provides a panel television receiver equipped with a liquid crystal display panel in which scanning electrodes and signal electrodes are arranged in a matrix. , a plurality of LSIs for driving signal electrodes, and the video signal A/D converted by the A/D converter is supplied to each of the LSIs for driving signal electrodes via the LSI for driving scanning electrodes. It is characterized by this.

[Function] By configuring as described above, the output terminals of the video signal and timing signal to be supplied from the scanning electrode driving LSI to the signal electrode driving LSI can be arranged side by side on the board, making it easy to implement. , which simplifies wiring.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the external structure of a liquid crystal television receiver, and numeral 10 in the figure is a receiver case. The front of this case 10 includes a television image display window 11, a VHF channel display section 12a, and a UHF channel display section 12a.
A channel display section 12b and a sound emitting section 13 are provided. A glass plate is attached to the front surface of the display window 11 and the channel display sections 12a and 12b, and the sound emission section 13 has a large number of small holes 15 and 1 for sound emission.
5 is drilled. Further, on the upper side of the case 10, there is a slide switch operation knob 1 that serves as a power switch and a VHF-UHF changeover switch.
6, and furthermore, although not shown, on the side of the case 10, there is an external power supply used when using an external DC power supply (a battery box sold as an accessory part of this television receiver). A connection port and a connection port for an external antenna (for example, an outdoor antenna) are provided. Further, a rod antenna 17 is attached to the upper end of one side of the case 10. The base of the rod antenna 17 is rotatably held by a hinge 18, and is stored in the upper part of the case 10 when not in use.

Next, the internal configuration of the television receiver will be explained.

First, the circuit configuration of the television receiver shown in FIG. 2 will be explained. In this television receiver, the circuit board is the antenna board 100,
It is divided into a knob board 110, a linear board 120, a power supply circuit board 130, a display drive control circuit board 140, and a display drive circuit board 150, and each board 100-
150 constitutes a circuit that will be described later. In addition to the above boards 100 to 150, tuner 16
0, speaker 170, panel type image display device 18
0 is set. As the panel type image display device 180, for example, a dot matrix liquid crystal display panel or an electroluminescent display panel is used. In this embodiment, an electroluminescent (EL) panel is provided on the back side of the dot matrix liquid crystal display panel 181 for illumination. Lighting panel 182
The dot matrix liquid crystal display panel 181 includes:
For example, a double matrix type with a display dot count of 120 x 160 and a TN (twisted nematic) type that is driven at a duty of 1/65.6 is used.

A rod antenna 17 provided in the receiver and an external antenna connection jack are connected to the antenna board 100. The television radio waves received by the rod antenna 17 or external antenna are transmitted to the tuner 16.
Sent to 0. Further, the knob board 110 is provided with a tuning knob 111 for selectively operating television radio waves, and the operation signal is sent to a circuit configured on the linear board 120. The linear board 120 is provided with a tuner power supply circuit 121, a tuning control circuit 122, a filter circuit 123, a linear circuit 124, and an audio amplification circuit 125. The tuning control circuit 122 provides a tuning signal to the tuner 160 in accordance with the operation from the tuning knob 111. This tuner 160 is a rod antenna 1
7 or an external antenna is selected according to a tuning signal from a tuning control circuit 122, converted to an intermediate frequency, and outputted to the filter circuit 123. This filter circuit 123 passes only the frequency components of the desired channel selected by the tuner 160, and removes the frequency components of adjacent channels. and,
The linear circuit 124 amplifies the intermediate frequency signal output from the filter circuit 123, and then performs video detection or the like to separate the video signal, audio signal, and synchronization signal.

The audio signal output from the linear circuit 124 is amplified by the audio amplification circuit 125 and then sent to the speaker 170, where it is output as audio. Further, the synchronization signal output from the linear circuit 124 is sent to a circuit configured on the power supply circuit board 130, and the video signal and synchronization signal are sent to a circuit configured on the display drive control circuit board 140.

The power circuit board 130 includes a power circuit 131
and a panel drive circuit 132 are provided, and the power supply circuit 131 supplies an operating voltage to the tuner power supply circuit 121 and a display drive power supply circuit 144 to be described later. In addition, the panel drive circuit 132 supplies a light emission operating voltage to the EL lighting panel 182 via a communication circuit 145 formed on the display drive control circuit board 140 based on a synchronization signal from the linear circuit 124, and A switching signal is applied to a circuit configured in 140. the above
The EL lighting panel 182 is the liquid crystal display panel 181
By illuminating the screen from the back side, it is possible to display a bright screen with good contrast and easy-to-see images. The display drive control circuit board 140 is provided with an analog/digital conversion circuit (hereinafter referred to as an A/D converter) 141, an auto level control circuit 142, a display drive control circuit 143, and a display drive power supply circuit 144. The output voltage of the display drive power supply circuit 144 is controlled ON/OFF by a switching signal from the panel drive circuit 132, and the output voltage is configured in the display drive control circuit 143 and the display drive circuit board 150. It is supplied to the display drive circuit 151 as an operating power source. The auto level control circuit 142 detects the level of the video signal from the linear circuit 124 and provides an upper limit reference potential V _H and a lower limit reference potential V _L to the A/D converter 141 . The A/D converter 141 converts the video signal from the linear circuit 124 into 4-bit, 16-gradation digital data using the reference potentials V _H and V _L and inputs it to the display drive control circuit 143 .
The display drive circuit 143 operates in synchronization with the synchronization signal from the linear circuit 124, supplies a drive signal to the scanning side electrode of the dot matrix liquid crystal display panel 181, and supplies the A/D to the display drive circuit 151.
Outputs 4-bit data from converter 141.

Figure 3 shows each of the substrates 100 to 150 shown in Figure 2.
This figure shows the connection between the tuner 160 and the image display device 180, in which a flexible substrate 200 led out from the side of the display drive control circuit board 140 is connected to the scanning side electrode terminal of the liquid crystal display panel 181 by thermocompression bonding. Flexible substrates 201, 201 led out from the display drive circuit board 150 are connected to the terminals of the signal side electrodes of the liquid crystal display panel 181, and the lead wires 182a of the EL lighting panel 182 are connected to the terminals of the signal side electrodes of the display drive control circuit board 140.
It is connected to the communication circuit 145 (see FIG. 2) with the EL drive circuit 132 by soldering, and also connects the display drive control circuit board 140 and the display drive circuit board 15.
0 and are connected to each other by thermocompression bonding of a flexible cable 202. That is, the image display device 180 (liquid crystal display panel 181 and EL illumination panel 182), the display drive control circuit board 140, and the display drive circuit board 150 are connected to each other and put together as a display unit A. Further, the power supply circuit board 130 is used as a single power supply circuit unit B, and the power supply circuit board 130 is connected to the display drive control circuit board of the display unit A via a flexible cable 203 soldered to the connection part thereof. 140 is removably contact-connected, and the linear board 120 is fixedly connected by soldering.
The linear board 120 and the tuner 160 constitute a linear unit C and a tuner unit D, respectively, and the tuner 160 has a flexible cable 204 soldered to its connection part.
It is designed to be removably contact-connected to the knob board 110 through the connector, and fixedly connected to the linear board 120 by soldering. Further, the tuner 160 and the antenna board 1
00 is connected by soldering via a lead wire 205.

However, the liquid crystal panel 181 has its signal electrode group divided into four blocks as shown in FIGS. ,2
1c and 21d drive the display for each block. This is done for the following reasons.

That is, in this embodiment, since the dot matrix liquid crystal display panel 181 is of the double matrix type as described above, the number of signal side electrodes is 320. The total number of terminals is 320 + α (here α is the number of terminals for inputting control signals, etc.).
Although LSI is required, large-scale multi-terminal
LSIs are quite expensive and lack versatility, so using large LSIs with multiple terminals is disadvantageous in terms of cost. Therefore, in this embodiment, the screen of the double matrix type dot matrix liquid crystal display panel 181 is divided into 1/4 of 4 as shown in FIG.
It is divided into three blocks a, b, c, and d, and the terminals Y ₁ to Y ₈₀ of the signal side electrodes of each block a, b, c, and d are
_Y81 to _Y160 , _Y'1 to _Y'80 , _Y'81 to _Y'160 are the four signal side electrode driving LSIs 21a, 21b, 21c,
21d respectively to connect the liquid crystal display panel 181.
The screen is driven 1/4 screen at a time. In this way, the LSIs 21a, 21b, 21c,
21d can be a small one with 100 terminals, and this
100-pin LSIs are highly versatile and inexpensive, making it possible to reduce costs. Furthermore, since the number of scanning side electrodes of the double matrix type dot matrix liquid crystal display panel 181 is 60, the scanning side electrode driving LSI 21e shown in FIG. 5 provided on the display drive control board 140 is also a 100-pin one. That's fine.

FIG. 5 shows the connection state between the liquid crystal display panel 181, the signal side electrode driving LSIs 21a to 21d, and the scanning side electrode driving LSI 21e. As mentioned above, the scanning side electrode driving LSI 21e has A/
4-bit data is input from the D converter 141, and horizontal and vertical synchronization signals are input from the linear circuit 124. Above LSI21e
creates various timing signals such as clock _pulses φ ₁ , _{φ 2} , sampling clock φ _S , latch pulse φ _L , frame pulse _φ At the same time, four chip enable signals CE ₁ to CE ₄ are generated every 4H period.
The LSI 21e has a liquid crystal display panel 18.
1, and sequentially selects the signal-side electrode driving LSIs _21a to _21d using chip enable signals _CE1 to _CE4 .
4-bit data and the various timing signals mentioned above are provided. The LSIs 21a to 21d connect signal electrode terminals _Y1 to _Y80 , _Y81 to the liquid crystal display panel 181 according to data and timing signals from the LSI21e.
Y ₁₆₀ , Y′ ₁ to Y′ ₈₀ , Y′ ₈₁ to Y′ ₁₆₀ are sequentially selected and driven for display.

In addition, the four signal side electrode driving LSIs 21a
~21d on the 150th side of the display driving circuit board, in the normal mounting method, the 150th side of the circuit board
The printed wiring that connects the LSIs and the printed wiring that is connected to the terminals of the signal side electrodes of the liquid crystal display panel 181 are mixed up, making the routing of the printed wiring complicated, and the circuit board 150 also has to be made larger. Therefore, in this embodiment, as shown in FIG.
21a and 21b and 21c and 21d are arranged so as to be line symmetrical to each other, and further LSI2
1b and 21d are respectively attached to the circuit board 150 by forming the terminals correctly, and the LSIs 21a and 21c are
The terminals are reverse formed and attached to the circuit board 150 upside down. In addition, in the figure, 1 → 20, 21 → 50, 51 → 70, 71
→100 indicates the terminal number of each LSI 21a to 21d. In this way, the four LSIs 21a to 2
1d, a pair of LSIs 21a and 21b
and common terminal 51→7 of 21c and 21d
Since the wires 0 can be connected by the shortest distance printed wires 31, 31, it is possible to simplify the routing of the printed wires on the circuit board surface and to reduce the size of the circuit board 150.

[Effects of the Invention] As described above, according to the present invention, in a panel television receiver equipped with a liquid crystal display panel in which scanning electrodes and signal electrodes are arranged in a matrix, an A/D converter performs an A/D converter. The D-converted video signal is once received by one scanning electrode driving LSI, and then distributed and supplied to multiple signal electrode driving LSIs along with various timing signals. Wiring to the LSI can be eliminated, and the LSI for driving signal electrodes
Since the signal supply lines to the scanning electrode driving LSI can be concentrated at one location, the wiring of the circuit can be simplified.

In addition, as a result, by outputting the timing signal that controls the synchronization of the video signal and this video signal from the same LSI chip, clips that are more likely to occur due to impedance mismatches, variations in wiring capacitance, etc. will occur if the chips are different. It also has the additional effect of being able to reliably prevent tectonic passes.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a front view showing the external configuration, FIG. 2 is a block diagram showing the overall circuit configuration, and FIG. 3 is a diagram showing each board shown in FIG. 2. A diagram showing the connection relationship between the tuner and the image display device, Figure 4 is an enlarged view of the liquid crystal display panel, Figure 5 is a diagram showing the connection relationship between the liquid crystal display panel and the display driving LSI, and Figure 6 is the display drive circuit. FIG. 3 is an enlarged view of the substrate. DESCRIPTION OF SYMBOLS 10... Case, 11... Television image display window, 12a, 12b... Channel display part, 17...
Rod antenna, 21a to 21d...LSI for driving the signal side electrode, 21e...LSI for driving the scanning side electrode, 12
0... Linear board, 130... Power supply circuit board, 140
...Display drive control circuit board, 150...Display drive circuit board, 180...Panel type image display device, 181...
LCD display panel.

Claims (1)

[Claims] 1. In a panel television receiver equipped with a liquid crystal display panel in which scanning electrodes and signal electrodes are arranged in a matrix, one scanning electrode driving LSI and a plurality of signal electrode driving LSIs are provided. LSI for driving the scanning electrodes mentioned above.
A timing generation circuit is provided in a free area, and the video signal A/D converted by the A/D converter is once input to the above-mentioned scanning electrode driving LSI, and from this scanning electrode driving LSI, the A/D A panel type television receiver characterized in that the converted video signal and timing signal are supplied to each of the signal electrode driving LSIs.