PLASMA TVs _ FUNCTION OF PARTS & GENERAL FAULTS

PARTS AND FUNCTIONS

PART NAME	MAIN FUNCTION
Y-Board ( Scan Driver )	Connected to Scan electrode(Y-electrode) & FPC for Scan & Sustain drive.
Z-Board ( Common Sustain driver)	Connected to Sustain electrode(Z-electrode) and FPC for Sustain drive.
X-Board ( Address Driver ).	Connected to Address electrode(X-electrode) of bottom plate and FPC X-Board ( Address Driver ) for Address drive.
Control Board.	Creates Display Data & Driver Timing for video, audio signal from outside and distributes to X, Y, Z Board.
DC/DC-2 Board.	Converts Vs, Val, Vcc voltage into Circuit Logic Voltage(5V) and Val, Vs, DC/DC-2 Board Vs, Vsetup voltage to distributes to X, Y, Z Board.
FPC ( Flexible Plate Circuit )	Connects PCB and panel pattern by line to line.
ACF (Anisotropic Conductive Film)	A Filler between panel and FPC, which is used as thermo-compression material to connect the pattern of FPC & panel(Glass). Composed of thermoset polymers and conductive metal powder(Ni, Au).
Heat Sink	Metal plate attached to the back of panel with adhesives, which absorbs and emits the heat from driving.
COF ( Chip On Film )	Integrated form of IC Chips on PCB and FPC, which makes the structure of PCB simple and small.

DEFINITION OF DEFECTS

Fault	Condition	Cause
Non lighting Cell Defect	Cell is always OFF	Particles or structural fault of cell.
Flashing Cell Defect	Cell repeats On/Off	Particles or structural fault of cell.
Non-extinguishing Cell Defect	Cell is always ON	Particles or structural fault of cell.
High Intensity Cell Defect	Cell is considerably brighter than others or different color appears.	Particles or structural fault of cell.
Quantizing Noise	Several luminance layer is seen in gradations of dark to bright.  Especially a luminance layer of contour form is seen on human faces.	The difference of brightness in the same gradation between lines with heavy load and lines with light load according to pictures. The layer is seen by skipping over neighboring gradation for White Balance & compensation with digital.
Contour Noise	Contour noise appears as several false contours of objects on moving image due to the time difference of gradation.	PDP is a device displaying color by dividing seconds, so viewers’ sight follows image of video picture.  Contour noise is having a false contour by the shade of the previous picture being added to the shade of current   picture.
Image Retention	The afterimage of the   previous image continues after signal input and removal, which disappears in minutes.	Memory Effect which is specific characteristic of AC PDP.
Image Sticking	The previous afterimage is seen when changing a certain pattern to different patterns after displaying for a long time.	Degradation of phosphor in fixed pattern which is displayed for hours.
Mis-writing	Many unstable cells in gradation. Mis-writing pattern are ON/OFF.	Unstable gradation signal when driving.
Maldischar Ge: Flashing Type	Cells which supposed to be Off repeat On/Off and are spread irregularly.	Incomplete removal of wall charge, space charge in Reset period.
Maldischar Ge:  Luminesce nt Spot Type	Cells repeat On/Off in abnormal bright color and are spread irregularly (mostly in White, Gray Pattern)	Unequal condition of cell discharge by the uneven structure of panel. Shift of Priming Charge by the structural fault of unit cells.
Crosstalk	Cell that supposed to be Off flashes unnecessarily on certain places and tends to spread over time.	Shift of Priming Charge by the structural fault of unit cells.  Polluted Cell
Spot	Colors in some part are different. Spot with normal part.	Pollution of PCB while Manufacturing.
Over-discharge	Over-discharge in some part, which looks like stained spots especially in single or white pattern.	Pollution or unequal structure in some part on panel.
Add Open	No lighting of vertical lines which are supposed to be ON	Address electrode Open. Fault on X-Board, Control-Board, compressed part of FPC.
Add Short	Vertical lines which supposed to be off are light up.	Fault on X-Board, Control-Board, compressed part of FPC.
Sus Open.	No lighting of horizontal lines which supposed to be On	Sustain(Z), Scan(Y) electrode Open, Dielectric breakdown. Fault on Z, Y-Board, Control-Board, compressed part of FPC.
Sus Short	Horizontal lines which supposed to off are lit up.	Sustain(Z), Scan(Y) electrode Short. Fault on Z, Y-Board, Control-Board, compressed part of FPC
Dielectric Breakdown.	No lighting of vertical lines which supposed to be On.	Electrode(Z, Y) breaking by high heat generated at dielectric breakdown by the fault(bubble, particle) inside of upper dielectric layer.
White Line.	Some vertical lines radiate brighter than normal.	Defect of electrical mechanism of Add Driver - X-Board.