Hi everyone,
This is my first public posting to this forum so "Hi" to everyone and sorry if some of the following questions seem a little "dumb" on my part.
I am a semi retired ex-tv service chap here in the UK who has spent many years in electronics both as a hobby and as a paying job. I enjoy "tinkering" and recently had cause to scrap an old LG 50PX4D plasma tv but as part of the strip-down and recovery of components I found myself curious about the general operation of plasma displays.
Following some research on the Internet I stumbled upon a posting from back in 2013 entitled "How a plasma display panel (PDP) works" on this forum by tom66 and was very impressed by the detail. I also read an application note from the International Rectifier company (an-1088) both of which have gone some way towards improving my understanding of plasma display technology.
As part of my tinkering and to satisfy curiosity I should like to light-up a few pixels on the old panel. I could just use "brute force" and connect a few electrodes at random to a tesla coil but aside from a few coloured "flashes" from the display I dont think I would learn very much :-)
So my plan is to apply a few static DC Voltages to selected panel pins via current limiting resistors to light-up a few pixels but a few things still "bug" me regarding the operation of plasma panels. Reading the IR application note the wording implies that the panel pixels need to be driven with an AC waveform in order to remain illuminated, is that correct or can a pixel be turned-on and remain lit with only DC Voltages applied?
The application note also describes a sort of generic plasma display cell with five electrodes per pixel, x,y and three "address" electrodes which appear to be for the R,G,B primary colours. Looking at my panel I am a little unsure as to which connections peform these functions. At first sight I would have said the panel does not appear to have enough electrodes to support the number of pixels required for a HD display but I am obviously missing something. The only connections I am certain of are those to the "Z-Sustain" pcb which appear to be three broad copper strips. Would these be the R,G,B "common" electrodes perhaps?
In short, I supose I am asking what would be the theoretical minimum connections required in order to light-up a selected pixel or group of pixels and do plasma display panels contain any "in-built" electronics for addressing the pixels or are they just gas-filled cells addressed by a matrix as the application note implies? Would it be safe for the PDP to simply connect a few DC Voltages between pins (with current limiting) in order to de-mystify the connections and light-up a few pixels?
Regards,
Des (electroyeti)
This is my first public posting to this forum so "Hi" to everyone and sorry if some of the following questions seem a little "dumb" on my part.
I am a semi retired ex-tv service chap here in the UK who has spent many years in electronics both as a hobby and as a paying job. I enjoy "tinkering" and recently had cause to scrap an old LG 50PX4D plasma tv but as part of the strip-down and recovery of components I found myself curious about the general operation of plasma displays.
Following some research on the Internet I stumbled upon a posting from back in 2013 entitled "How a plasma display panel (PDP) works" on this forum by tom66 and was very impressed by the detail. I also read an application note from the International Rectifier company (an-1088) both of which have gone some way towards improving my understanding of plasma display technology.
As part of my tinkering and to satisfy curiosity I should like to light-up a few pixels on the old panel. I could just use "brute force" and connect a few electrodes at random to a tesla coil but aside from a few coloured "flashes" from the display I dont think I would learn very much :-)
So my plan is to apply a few static DC Voltages to selected panel pins via current limiting resistors to light-up a few pixels but a few things still "bug" me regarding the operation of plasma panels. Reading the IR application note the wording implies that the panel pixels need to be driven with an AC waveform in order to remain illuminated, is that correct or can a pixel be turned-on and remain lit with only DC Voltages applied?
The application note also describes a sort of generic plasma display cell with five electrodes per pixel, x,y and three "address" electrodes which appear to be for the R,G,B primary colours. Looking at my panel I am a little unsure as to which connections peform these functions. At first sight I would have said the panel does not appear to have enough electrodes to support the number of pixels required for a HD display but I am obviously missing something. The only connections I am certain of are those to the "Z-Sustain" pcb which appear to be three broad copper strips. Would these be the R,G,B "common" electrodes perhaps?
In short, I supose I am asking what would be the theoretical minimum connections required in order to light-up a selected pixel or group of pixels and do plasma display panels contain any "in-built" electronics for addressing the pixels or are they just gas-filled cells addressed by a matrix as the application note implies? Would it be safe for the PDP to simply connect a few DC Voltages between pins (with current limiting) in order to de-mystify the connections and light-up a few pixels?
Regards,
Des (electroyeti)
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