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FAN7930B • Rev. 1.0.2

18

Typical Application Circuit

Application

Device

Input Voltage

Range

Rated Output

Power

Output Voltage

(Maximum

Current)

LCD TV Power Supply

FAN7930B

195W

390V (0.5A)

Features

Average efficiency of 25%, 50%, 75%, and 100% load conditions is higher than 95% at universal input.

Power factor at rated load is higher than 0.98 at universal input.

Total Harmonic Distortion (THD) at rated load is lower than 15% at universal input.

Key Design Notes

winding. The power consumption of R103 is quite high, so its power rating needs checking.

Because the input bias current of INV pin is almost zero, output voltage sensing resistors (R112~R115) as high

as possible. However, too-high resistance makes the node easily affected by noise. Thus values need to strike a

balance between power consumption and noise immunity.

Quick charge diode (D106) can be eliminated if output diode inrush current capability is enough. Thought D106,

system operation is normal due to the controller’s highly reliable protection features.

1. Schematic

Figure 44.

Demonstration Circuit