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Ersa i-CON 1 soldeerstation display achtergrond verlichting LED's vervanging

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Ersa i-CON 1 soldering station display backlight replacement, Backlight schematics: crwdns2935265:00crwdnd2935265:01crwdnd2935265:01crwdne2935265:0
Backlight schematics

  • After analyzing the original backlight connections, it became clear why it fails: the Chinese designers who created the display wanted to save space and money by connecting the LEDs in parallel.

  • However, since each LED has a slightly different threshold voltage, one of them draws more current and fails prematurely. The remaining two LEDs then experience even higher currents and burn out soon afterwards.

  • To address this issue, I decided to change the connection according to the lower schematic. I shorted the original 22R resistors and put a 220R resistor in series with each new LED.

Achtergrondverlichting schema's

Ik analyseerde de originele backlight-aansluitingen en het is duidelijk waarom de LEDS doorbranden: Chinese kameraden die het scherm ontwierpen, wilden wat geld en/of ruimte besparen en sloten de LED's parallel aan.

Natuurlijk heeft elke LED een iets andere drempelspanning. Als gevolg hiervan trekt een van hen meer stroom en valt voortijdig uit (brandt open). De resterende twee LED's worden dan aan nog hogere stromen blootgesteld en branden kort daarna ook door.

Dus besloot ik de verbinding te veranderen volgens het onderste schema - ik heb de originele 22R-weerstanden kortgesloten en een 220R-weerstand in serie gezet met elke nieuwe LED.

[title] Backlight schematics
-[* black] I analyzed original backlight connections and it's apparent why it fails: Chinese comrades who designed the display wanted to save some money and/or space and connected the LEDs in parallel.
-[* black] Of course, every LED has slightly different threshold voltage. As a consequence, one of them draws more current and fails (burns open) prematurely. The remaining two LEDs are then subjected to even higher currents and burn soon afterwards, too.
-[* black] Thus I decided to change the connection according to the lower schematic - I shorted the original 22R resistors and put a 220R resistor in series with each new LED.
+[* black] After analyzing the original backlight connections, it became clear why it fails: the Chinese designers who created the display wanted to save space and money by connecting the LEDs in parallel.
+[* black] However, since each LED has a slightly different threshold voltage, one of them draws more current and fails prematurely. The remaining two LEDs then experience even higher currents and burn out soon afterwards.
+[* black] To address this issue, I decided to change the connection according to the lower schematic. I shorted the original 22R resistors and put a 220R resistor in series with each new LED.

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