Re: Ordering SMD LED for backlight
here dear friend what i am talking on.. the main roll always with TV Back light LED we need to take care on these facts.
how much we have on One LED
1- Forward Current (IF )
2- Pulse Forward Current (IFp)
3- Reverse Current (IR): uA
4- Reverse Voltage (VR): V (mA)
5- Power Dissipation (PD) W most 1w
6- Operating Temperature (Topr):
7- Storage Temperature (Tstg: always = (Topr)
8- Soldering Temperature Tsld):
the LG sheet was refer to Double chip. Single one had other way for measurement and sheet dialogue.
look on the first photo OP posted the label. 6V all in one line 50 pieces socket type with each 2 wires. ( its one line PSU out )
the second label photo nothings special as we do know size and type but it tell us that this type had 100 lu. this is not always described on the strips label. as each manufacture use its own way to described .
the subject become interesting. so i find its not bad we discusses it here ..
i would like to add one Facts that the critical point always to LED Backlight the starting from cold start the tv.
PSU will give the high level after it receive the BL_ON signal untill the firmware come in place to reduce the current. ( this why many TV manufacture didn't install main switch to the AC Line. so TV remain in STB.
other manufacture ( Most Chinese brand ) they add the control part at the eeprom start up script to sent BL-ON under value control. this we can find it when we log in SM. and under LED back light section. we will find the way it work. for example Hisense they had most always the BL value range like 0-20-50-80-100
where 0=0, 20=30, 50=80, 80=90 , 100=100,
in short words it mean user put the BL in setting of 50. but in fact its 80.
such TV sets which work on this script add to boot eeprom suffer always corrupted firmware or damage SPI Flash. so other manufacture they make the SMD LED can handle this high power at start on. better than they will face other problem with MB or firmware or boot .bin driver.
Originally posted by budm
View Post
how much we have on One LED
1- Forward Current (IF )
2- Pulse Forward Current (IFp)
3- Reverse Current (IR): uA
4- Reverse Voltage (VR): V (mA)
5- Power Dissipation (PD) W most 1w
6- Operating Temperature (Topr):
7- Storage Temperature (Tstg: always = (Topr)
8- Soldering Temperature Tsld):
the LG sheet was refer to Double chip. Single one had other way for measurement and sheet dialogue.
look on the first photo OP posted the label. 6V all in one line 50 pieces socket type with each 2 wires. ( its one line PSU out )
the second label photo nothings special as we do know size and type but it tell us that this type had 100 lu. this is not always described on the strips label. as each manufacture use its own way to described .
the subject become interesting. so i find its not bad we discusses it here ..
i would like to add one Facts that the critical point always to LED Backlight the starting from cold start the tv.
PSU will give the high level after it receive the BL_ON signal untill the firmware come in place to reduce the current. ( this why many TV manufacture didn't install main switch to the AC Line. so TV remain in STB.
other manufacture ( Most Chinese brand ) they add the control part at the eeprom start up script to sent BL-ON under value control. this we can find it when we log in SM. and under LED back light section. we will find the way it work. for example Hisense they had most always the BL value range like 0-20-50-80-100
where 0=0, 20=30, 50=80, 80=90 , 100=100,
in short words it mean user put the BL in setting of 50. but in fact its 80.
such TV sets which work on this script add to boot eeprom suffer always corrupted firmware or damage SPI Flash. so other manufacture they make the SMD LED can handle this high power at start on. better than they will face other problem with MB or firmware or boot .bin driver.
Comment