Master Electronics Repair !

Welcome to Master Electronics Repair! website.Here you will find:Service Modes, Circuit Diagrams,Service manuals, Firmware Update procedure, Disassemble procedure, Universal remote control setup codes, Troubleshooting, Diagnosing, Measuring, and more.... of many of LCD/LED TV/Displays,others various electronic apparates,trough many technical notes and tips/tricks to help repairing/fixing Troubles/ faults,for electrical technicians.This site helps you to save the Earth from electronic waste!

Richtige Fernseher haben Röhren!

Richtige Fernseher haben Röhren!

In Brief: On this site you will find pictures and technical information about Service Modes, Circuit Diagrams, Firmware Update procedure, Disassemble procedure, Universal remote control set-up codes, Troubleshooting and more....

If you go into the profession, you will obtain or have access to a variety of tech tips databases HERE IT IS Master Electronics Repair !.

These are an excellent investment where the saying: 'time-is-money' rules. However, to learn, you need to develop a general troubleshooting approach - a logical, methodical, method of narrowing down the problem. A tech tip database might suggest: 'Replace C536' for a particular symptom. This is good advice for a specific problem on one model. However, what you really want to understand is why C536 was the cause and how to pinpoint the culprit in general even if you don't have a service manual or schematic and your tech tip database doesn't have an entry for your sick TV or VCR.

While schematics are nice, you won't always have them or be able to justify the purchase for a one-of repair. Therefore, in many cases, some reverse engineering will be necessary. The time will be well spent since even if you don't see another instance of the same model in your entire lifetime, you will have learned something in the process that can be applied to other equipment problems.
As always, when you get stuck, checking out a tech-tips database may quickly identify your problem and solution.In that case, you can greatly simplify your troubleshooting or at least confirm a diagnosis before ordering parts.

Happy repairing!

Today, the West is headed for the abyss. For the ultimate fate of our disposable society is for that society itself to be disposed of. And this will happen sooner, rather than later.

How to use the site:

- If you landed here via any Search Engine, you will get what you searched for and you can search more using the search this blog feature provided by Google. You can visit more posts scrolling the left blog archive of all posts of the month/year,
or you can click on the main photo-page to start from the main page. Doing so it starts from the most recent post to the older post simple clicking on the Older Post button on the bottom of each page after reading , post after post.

You can even visit all posts, time to time, when reaching the bottom end of each page and click on the Older Post button.

- If you arrived here at the main page via bookmark you can visit all the site scrolling the left blog archive of all posts of the month/year pointing were you want , or more simple You can even visit all blog posts, from newer to older, clicking at the end of each bottom page on the Older Post button.
So you can see all the blog/site content surfing all pages in it.

- The search this blog feature provided by Google is a real search engine. If you're pointing particular things it will search IT for you; or you can place a brand name in the search query at your choice and visit all results page by page. It's useful since the content of the site is very large.

Note that if you don't find what you searched for, try it after a period of time; the site is a never ending job !

..............The bitterness of poor quality is remembered long after the sweetness of todays funny gadgets low price has faded from memory........ . . . . . .....
Don't forget the past, the end of the world is upon us! Pretty soon it will all turn to dust!

©2010, 2011, 2012, 2013, 2014 Frank Sharp - You do not have permission to copy photos and words from this blog, and any content may be never used it for auctions or commercial purposes, however feel free to post anything you see here with a courtesy link back, btw a link to the original post here , is mandatory.
All posts are presented here for informative, historical and educative purposes as applicable within fair use. NOTHING HERE IS FOR SALE !

Thursday, 21 March 2019

LG 47LG90 - MAIN BOARD - LAYOUT - VOLTAGE CHART

MAIN PWB

The Main PWB contains the MICRONAS chip IC1000.
This IC is a Full-HD Rate Converter with Motion Blur Removal and Film De-Juddering for 1080p 100/120 Hz LCD panels.
Vector Based Motion Compensation with Frame Rate Conversion (eliminates the need for 3:2 Pull Down)
Internal Dual 10 bit LVDS input
Quadruple 12 bit LVDS output.
Motion Blur Removal increases the video frames by Interpolating a new image frame between each original frame (Motion Estimated Data Insertion) MEDI
Juddering is a phenomenon which appears on film based programming due to the 24 frames per second system used for recording, the picture develops visual artifacts when converted to 60 frames per second. 3:2 Pull Down was developed to eliminate this problem. Frame Rate Conversion (Real Cinema) eliminates the need for 3:2 Pull Down.
TruMotion 120Hz ( Vector Based Motion Compensation)
TruMotion 120 Hz can reduce blurring on fast moving scenes. TruMotion carefully analyses the picture signal by using advanced algorithms to automatically calculate a new image frame between each original frame (MEDI).

MAIN PWB LAYOUT [Click on images to Enlarge]

COMPONENT LAYOUT

MAIN BOARD - BACK VIEW

MAIN PWB [FRONT SIDE] REGULATORS

MAIN PWB [BACK SIDE REGULATORS] SIDE-1

MAIN PWB [BACK SIDE REGULATORS] SIDE - 2

MAIN PWB [BACK SIDE REGULATORS] SIDE - 3

MAIN PWB LD803 FUNCTION

Use LD803 as a visual aid. This lets you know if the +5V is being converted to 3.3V for the BCM chip IC100. If LD803 is illuminated GREEN, +3.3V is OK.
Note: Only ½ of the dual LED is used.

LD 803 CIRCUIT

MAIN PWB TUNER, VIDEO AND SOUND IF [SIF] CHECK PIN LOCATION

If you leave the shield on you can still access the same pins. Be careful not to accidentally ground out your test lead on the shield. (Note: This is a picture from a different model, but the concept is the same.

MAIN PWB CONNECTOR [P-800] VOLTAGE & RESISTANCE

Pin 21 BRI(ADIM) Is Fixed and is not used
Diode Mode values taken with all Connectors Removed.
PDIM Pin 22can vary according to type of signal being processed, OSD Backlight setting. 0.4V 0% to 3.4V 100% and the Intelligent Sensor. Output controlled from the BCM chip.