BUCK ROYER ADVANTAGES:

1. Step-down voltage regulator (Book regulator) adjusts input voltage to Royer oscillator, providing both line and load regulation.
2. Lamp brininess is extremely intensities to both static and dynamic input voltage changes.
Conversion Efficiency is fairly constant across input voltage range.
3. Seff-ressonant Royer oscillator (transformer, ballast cap, PPS cap) provides law crest factor sine wave consent waveform to the lamp. CCFLs operate most efficiently with law (1.4 to 1.6) crest factors.

BUCK ROYER DISADVANTAGES:

1 Requires am components, resulting in higher cost and larger size.
2. Four power semiconductors, two power inductors and one PPs (Poly Phenelene Sulfide) high current capacitor burn power, reducing conversion efficiency. Very high quality components can be selected to regain some of these power losses, but high cost premiums and larger size must be paid.
3. Open circuit voltage is wry difficult to limit due to multiple resonances in the power circuit, lack of voltage feedback, and lack of frequency control from the controller IC. Phase circuits am prone to along and self destruction when operated open circuit (lamp unplugged or broken).
4. Buck regulator and Royer Oscillator operate asynchronously at different frequencies, making EMI and RFl room difficult to control.

DIRECT DRIVE DISADVANTAGES:

1. PWM regulation causes high lamp current crest factors when input voltage is more than 1.5 times the design minimum. This reduces nits/watt efficiency at high line to approxmimately the same as Buck/Royer dign. At low-Line Battery voltage levels) efficiency is 10-30% higher than Buck Royer inverters. Direct Drive efficiency is so high at 5V and UV that it makes up for Buck regulator losses in notebook systems, yielding comparable overall system efficiency while completely eliminating the disadvantage of high crest factors at high input voltages.

Here is a typical inverter input connector

This is a single coil Laptop inverter Circuit using transistors with a high frequency Astable Oscillators electronic circuits, schematics. the circuit at 12 volts will drive a 337mm backlight lamp or larger.

If you would like to build your own inverter for a test here is a circuit i designed for the electronics savvy who are stuck with a nice LCD unit but nobody has the inverter PCB in stock to sell you or the part # is none-existent, oh an amendment the oscillator capacitors should be 681pf. Yes we repair inverter PCBs on average at $66 no mater the size. Our address for mailing PCBs in for repair is at is at http://sonyrepair.home.att.net/Address.html

And here is a true AC Backlight Inverter Schematic Mosfet

And here is a true AC Backlight Inverter Schematic Transistor