[Breaking Down Wooo UT] 'Stunned' by Ultrathin Power Board [Part 4]

Dec 20, 2007
Nikkei Electronics Breakdown Team
The power board appeared when we removed the cream-colored sheet.
The power board appeared when we removed the cream-colored sheet.
[Click to enlarge image]
The components on the board are of uniform height.
The components on the board are of uniform height.
[Click to enlarge image]
Back side of the power board
Back side of the power board
[Click to enlarge image]

The Nikkei Electronics Breakdown Team started to analyze the power board at last. This is the power board of which Hitachi Ltd was so proud for its ultra low profile.

Yes, this is the component developed by Hitachi Media Electronics Co Ltd. Its thickness was reduced to 12.3mm, approximately 1/3 that of the power board used in existing LCD TVs.

We removed the mysterious cream-colored sheet covering the unit believed to be a power board, which it turned out to be. A glass epoxy board was used instead of paper phenol board, which is frequently used for the power board in recent TVs.

When we scrutinized the board, we could see that the components mounted on it were nearly all the same height. The height of components such as the transformer, heatsink, electrolytic capacitor and the relay were astonishingly uniform.

To be more precise, the transformer and heatsink were the tallest parts. Both measured about 9mm from the board surface. Of course, to reduce its thickness, the connectors were mounted so that they were connected from the sides.

We unscrewed the screws used to attach the board and removed it from the LCD panel module. We then checked the back of the board.

First, we noticed a hole at the position where the electrolytic capacitor was laid down. The hole might be there to accommodate the height. Looking at it more closely, we found a number of rubber sheets attached to the board. They may be spacers.

Anyway, the power board was definitely thin.

"I'm totally stunned," one of the engineers from a component manufacturer who attended the disassembly said with a sigh of admiration. "This is the thinnest level possible based on the present technologies," he continued.