Mixed signal chip firm AnalogicTech
is branching out into drivers for small active-matrix OLEDs and
large LCD TVs.
"We are looking at AMOLEDs for phones and the re-engineering of
TVs to replace CCFL [fluorescent] backlights with LEDs," CEO
Richard Williams told Electronics Weekly.
The firm has a proprietary BCD (bipolar-CMOS-DMOS) mixed-signal
chip process that uses trench isolation and implants, rather than
epitaxy and diffusion, and can therefore be made in
cost-depreciated former DRAM fabs.
"We can mix 3V, 12V and 30-60V in our isolated islands, all on
one chip, for a couple of implants for each voltage," said
Williams.
He sees LED backlights making rapid progress in TVs.
"Fluorescent tube backlights are going to die," said Williams.
"I wouldn't be surprised if they are banned because they have no
Energy Star rating, and they have mercury."
LEDs can be used as direct CCFL, or in a multi-pixel (or
'domain') backlight that increases contrast and reduces power,
because it supplies full intensity behind the brightest parts of
the image.
"There will be hundreds of domains, you could end up with 2,000
LEDs in 200 domains in the backlight," said Williams. "They reduce
current consumption by an average of six - depending on the
image."
As well as the backlights, AnalogicTech will also work on chips
for gamma correction and generating TV bias voltages, he added.
On the OLED display front, the firm has what Williams claims is
an innovative power supply waiting in the wings. "An AMOLED needs a
positive supply and a negative supply. These need a positive boost
converter and a negative boost converter," he said. "That's two
coils but we are privately sampling a PSU that independently
regulates the plus and minus rails from a single coil with a
measured efficiency comparable with dual converters."
Once again, gamma correction - this time to compensate for the
different characteristics of red, green and blue OLED materials, is
another target.
Its process is approaching the breakdown voltages required by
some AC-DC power supplies. Is AnalogicTech going there?
"We have not gone after the AC-DC market yet," said Williams. "I
think it is something we will eventually do, but I prefer chaotic
markets.
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