Hi,
I am working a Sharp LC-60LE640U and having a difficult time in finding either a LED strip replacement or individual LED to repair. Does anyone have any suggestions on where the strips can be found or the individual LED's to repair the existing strip?
The two strips are identified on the back with a label 5227ZZ and 5228ZZ. The individual LED's are 6 volt, qty 68 per strip, running two groups of 17 in parallel on each strip with the power supply utilizing four driver circuits.
The entire metal plate is stamped GA0361TPZZ. The TV is edge lit with all of the LED's located at the bottom of the panel.
I have read and searched on here for days, but no joy on finding individual replacements. The closest I have found through either Ebay or other sites is a rating of 150ma, LED P/N GM5FR2ZP20A.
https://ru.aliexpress.com/item/SHARP...740280331.html
I have also noted through searching that the expected current for some of these needs to be in the 300 to 400ma range, however my attempts to characterize a good one on the strip seems to indicate a much lower current level, especially if the LED's were operated in their nominal range of 6V.
Measured values from one LED on strip, voltage drop measured across LED:
5.8V = 59ma
6.0V = 72ma
6.2V = 112ma
6.4V = 134ma
As for measuring the power supply output I am not confident of the measured voltages. Since one LED strip had two bad LED's within one channel, that channel was dead and the backlight was only powered momentarily using the hold "Input" and "Vol -" when power was applied. The peak voltages captured with the DMM from high and low in respect to chassis were:
Chan 1 + = 192V Chan 1 - = 0V
Chan 2 + = 101V Chan 2 - = 14.4V
Chan 3 + = 101V Chan 3 - = 13.6V
Chan 4 + = 101V Chan 4 - = 12.9V
Seeing how those voltages would only bias the LED's at about 5.1V I suspect they are not accurate - 101V -14V = 87V / 17 = 5.1V
One other question is any possibility of locating the power supply schematic diagram - DPS-162KP A / RUNTKA932WJQZ for possibly modifying to limit current in the LED drive circuit?
And, just a side note if it has not been posted before, but I did purchase one of the cheap Chines LED testers - a model GJ2C. The constant current source in it is set to 30ma.
I am working a Sharp LC-60LE640U and having a difficult time in finding either a LED strip replacement or individual LED to repair. Does anyone have any suggestions on where the strips can be found or the individual LED's to repair the existing strip?
The two strips are identified on the back with a label 5227ZZ and 5228ZZ. The individual LED's are 6 volt, qty 68 per strip, running two groups of 17 in parallel on each strip with the power supply utilizing four driver circuits.
The entire metal plate is stamped GA0361TPZZ. The TV is edge lit with all of the LED's located at the bottom of the panel.
I have read and searched on here for days, but no joy on finding individual replacements. The closest I have found through either Ebay or other sites is a rating of 150ma, LED P/N GM5FR2ZP20A.
https://ru.aliexpress.com/item/SHARP...740280331.html
I have also noted through searching that the expected current for some of these needs to be in the 300 to 400ma range, however my attempts to characterize a good one on the strip seems to indicate a much lower current level, especially if the LED's were operated in their nominal range of 6V.
Measured values from one LED on strip, voltage drop measured across LED:
5.8V = 59ma
6.0V = 72ma
6.2V = 112ma
6.4V = 134ma
As for measuring the power supply output I am not confident of the measured voltages. Since one LED strip had two bad LED's within one channel, that channel was dead and the backlight was only powered momentarily using the hold "Input" and "Vol -" when power was applied. The peak voltages captured with the DMM from high and low in respect to chassis were:
Chan 1 + = 192V Chan 1 - = 0V
Chan 2 + = 101V Chan 2 - = 14.4V
Chan 3 + = 101V Chan 3 - = 13.6V
Chan 4 + = 101V Chan 4 - = 12.9V
Seeing how those voltages would only bias the LED's at about 5.1V I suspect they are not accurate - 101V -14V = 87V / 17 = 5.1V
One other question is any possibility of locating the power supply schematic diagram - DPS-162KP A / RUNTKA932WJQZ for possibly modifying to limit current in the LED drive circuit?
And, just a side note if it has not been posted before, but I did purchase one of the cheap Chines LED testers - a model GJ2C. The constant current source in it is set to 30ma.
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