JPH04366889A - Plasma display device - Google Patents

Abstract

PURPOSE:To instantaneously end full-illumination operation which prevents initial discharge delay by generating a signal which makes all electrodes of a plasma display panel illumination state simultaneously power-ON operation and detecting all the electrodes being in an illumination state. CONSTITUTION:A row electrode driving circuit 2 and a column electrode driving circuit 3 are connected to the electrodes of the plasma display panel 1 and a control circuit 4 controls display information and scan information required for them. When the display information is held in the illumination state for a time more than one screen scan, the plasma display panel 1 enters the full- illumination state. A full-illumination circuit 5 detects the power-ON operation and switches all the display information to the illumination state. A full- illumination detecting circuit 6 detects the full-illumination state and resets the signal of the full-illumination circuit 5. Thus, the full-illumination operation which prevents the initial discharge delay ends instantaneously regardless of whether the turn-on time of the plasma display panel 1 is short or long.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an AC refresh type plasma display device.

0002

2. Description of the Related Art Conventionally, as shown in FIG. 3, this type of AC refresh type plasma display panel display device has a plasma display panel 1 and a row drive circuit 2 and a column drive circuit 3 that drive the electrodes thereof. It has a control circuit 4 that generates a signal and a full lighting circuit 5. Control circuit 4
controls scanning information and display information necessary for the row drive circuit 2 and column drive circuit 3. The row drive circuit 2 and column drive circuit 3 convert signals from the control circuit 4 into drive voltages necessary for the plasma display panel 1 to obtain a desired display. Plasma display panels experience a lighting delay when the power is turned on. To prevent this, an all-lighting circuit 5 is provided to keep all electrodes lit for a certain period of time when the power is turned on.

0003

[Problems to be Solved by the Invention] This conventional plasma display panel display device has an all-lighting circuit 5 that lights up all electrodes for a certain period of time in order to prevent an initial discharge delay. There is a large variation in discharge delay time. This discharge delay time is called turn-on time, and the full lighting circuit 5 is set so that the lights are fully lit for a time that is sufficient to absorb this variation, generally about 5 to 10 seconds. Lights with a fast turn-on time turn on at the same time as the power is turned on and remain lit for a set period of time, while lights with a slow turn-on time turn on at the end of the set time. There was also the problem that if the lights did not start within the set time, the all-store lighting path would not work at all.

0004

[Means for Solving the Problems] The plasma display panel display device of the present invention includes a circuit that lights up all the electrodes at the same time as the power is turned on, and a detection circuit that detects whether all the electrodes are lit. When the lights turn on, the full lighting detection circuit operates and turns off the full lighting circuit, so that both early and slow turn-on times are fully lit for a fixed short period of time.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings. FIG. 1 is a block diagram of one embodiment of the present invention. A row electrode drive circuit 2 and a column electrode drive circuit 3 are connected to the electrodes of the plasma display panel 1, respectively. The control circuit 4 controls display information and scanning information necessary for the row electrode drive circuit 2 and column electrode drive circuit 3. If the plasma display panel 1 is kept lit for longer than the time required to scan one screen of display information, the plasma display panel 1 becomes fully lit. The all-lighting circuit 5 is a circuit that detects power-on and switches all the display information to a lit state. The full lighting detection circuit 6 detects the full lighting state and functions to release the signal from the full lighting circuit 5.

FIG. 2 is a detailed diagram of the entire lighting circuit 5 and lighting detection circuit 6 of this embodiment. In the figure, a D type flip-flop 51 has an input D connected to a logic power supply Vcc, and a clock input terminal CK connected to a resistor R1 and a capacitor C1. When the logic power supply is turned on in this state, the clock terminal CK rises with a delay of a time constant determined by the capacitance of the resistor R1 and the capacitor C1. The D flip-flop 51 outputs information at the input terminal D to the output Q when the clock terminal CK rises. In this case, the output Q becomes logic "H" and is output to the input 54 of the OR gate 52. One input 53 of the OR gate 52 is connected to the control circuit 4
Receives data input from the or gate 52,
It is output to the column electrode drive circuit 3. Input 54 is “H”
When this happens, the output 55 of the OR gate 52 also becomes "H", resulting in a fully lit state.

A resistor R2 is connected to the return side of the display power supply. The signal is applied from this resistor R2 to the input + of the operational amplifier 61 through the resistor R5. On the other hand, the input - of the operational amplifier 61 is placed at the midpoint between the resistor R3 and the variable resistor R4. When the voltage on the input + side becomes higher than the input - side, the operational amplifier 61 connects the inverter 62 through the resistor R6.
Outputs voltage to. The diodes D1 and D2 are inserted so that the voltage input to the inverter 62 through the resistor R6 does not exceed the logic power supply. The inverter 62 inverts the input signal, and when a positive voltage is input through the resistor R6, it outputs a logic "L" voltage, sets the reset terminal R of the D flip-flop 51 to "L", and outputs The full lighting state can be canceled by setting Q to "L". In other words, the resistors R3 and R4 are adjusted so that the voltage generated across the resistor R2 by the current flowing through the resistor R2 during full lighting is higher than the voltage divided by the resistors R3 and R4. Capacitor C2 is inserted so that the voltage generated across resistor R2 is averaged. It also forms a time constant with the resistor R5, and has the role of creating a time lag from when all the lights are turned on until when all the lights are turned off.

[0008]

[Effects of the Invention] As explained above, the present invention activates the full lighting circuit at the same time as the power is turned on, provides a detection circuit to detect when the full lighting is reached, and stops the full lighting circuit when the full lighting is reached. This has the effect that the entire lighting operation for preventing initial discharge delay is completed instantly regardless of whether the turn-on time of the plasma display panel is early or late. It also has the effect of ensuring that all lights are turned on.

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of the invention.

FIG. 2 is a detailed diagram of the all-on circuit and all-on detection circuit shown in FIG. 1;

FIG. 3 is a block diagram of a conventional plasma display device.

[Explanation of symbols]

1 Plasma display panel 2 Row electrode drive circuit 3 Column electrode drive circuit 4 Control circuit 5 Full lighting circuit 6 Full lighting detection circuit 51 D flip-flop 52 OR gates 53-55 Input/output line 61 Operational amplifier 62 Inverter R1-R6 Resistor C1, C2 Capacitor D1, D2 Diode Vcc Logic power supply

Claims (1)

[Claims] 1. A display device comprising a plasma display panel whose electrodes are covered with a dielectric material and its drive circuit, in which a circuit generates a signal that turns on all electrodes of the plasma display panel at the same time as power is turned on. . A plasma display device comprising: a circuit that detects that all electrodes are turned on and turns off the signal.