Have a powersupply board.
https://www.ebay.com/itm/404055262298If i connect the backlight to the PS...my lamp that i have in series for protection starts to pulsate 3-4 times after ps-on. (pfc ...which seems normal) , then the tv-led-backlight turns on and then off again after one second. The PSU restarts itself as soon as I turn on the backlight. (ps-on and bl-on +3.5V). Then it tries to turn on the backlight again and same behavoiur...it shuts down. There seems to be some problem that the current is to high and therefore the switching reboots. The tv has 2 ledstripes.. if i disconnect one of them...regardless of which one. The PSU starts and works and this ledbacklight is turned on. Now i can connect the second ledbacklight again (only two cables are for backlight)...the second one lights up and the PSU works. Is seems that there is a lot of current drawn at startup that makes the PSU to reboot.
BUT...the thing here. My bulb...that i use for protection (
) ..glows. 20% at least from full glow. Normally the bulb lights up and then turns off when working with SMPS. If it is lit...there is a short circuit. But here it is glowing at 20%.
Is this the same as partial short cut? Some component that are not 100% functional. That also causes the current limit to trigger when starting up but works if i disconnect one led and then connect it back again.
is this partly glowing protection bulb normal? i think if the PFC circuit somehow affects it and that it is normal or do you think that there is something wrong with led.driver part of the circuit? All other things works fine. 8V standby....12V after ps-on .... 24V output from led driver. But as soon there is a load on the ledside...the shutdown occurs.
Hope someone can just confirm or comment on this . Just for mee to be able to narrow it down a bit and not chasing things that maybee are not a problem. My opinion is that there is something partial shortcutting. Thanks,.
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