CCFL Backlight and

LCD Contrast Controllers

10

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PARAMETER

SYMBOL

MIN

TYP

MAX

UNITS

1100

1500

0.001376

0.005

435

Bias Voltage

16.3

32.6

V

Output Current

0.0245

A

T1 Turns Ratio (Sec/Pri) (Note 2)

n

171

T1 Resonating Inductance (Note 2)

0.000045

H

C9 Value (Note 3)

2.2E-07

F

C10 Value

1.5E-11

F

Royer Frequency

w

317820.86

rad/s

Reference Voltage

1.25

V

Second Volts Constant

sV

0.000008

2.4E-05

sV

R8 Current-Sensing Resistor

R8

555.36037

Ω

Secondary Voltage Phase vs. Tube Voltage

phi

-1.1776341

Radian

Secondary Limit Voltage

1350

T1 Center-Tap Limit Peak Voltage

11.164844

R5/R6

0.1341944

Ω/Ω

1.639E-06

s

L2 Inductance

L2

1.96E-05

2.4E-05

H

L2 Peak Currrent

1.22704

A

R4/R3

0.0398724

Ω/Ω

Input Voltage

5.978103

18

V

Table 2. CCFL Circuit Design Example (Note 1)

T1 Center-Tap Peak Voltage

9.3903817

Note 1:

To perform your own calculations for the parameters given in Table 2 (Design Example), use the equations given in Table

3 (Design Equations).

Note 2:

T1 = Sumida’s EPS207

Note 3:

C9 = Wima’s SMD 7.3 __/63

CCFL Specifications

LCD Contrast Voltage Specifications

Royer Specifications

MAX754 Specifications

CCFL Circuit Calculations

LCD Circuit Calculations

Application Circuit Operating Range