Microsemi

Integrated Products

11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570

Page 6

Copyright

© 2003

Rev. 1.0, 7/16/2004

LX1691

Enhanced Multi-Mode CCFL Controller

TM

®

]

ELECTRICAL CHA RACTERISTICS (CONTINUED)

LX1691

Parameter

Symbol

Test Conditions

Min

Typ

Max

Units

RAMP GENERATOR

Max Strike / Run Frequency Ratio

Ratio to run frequency, I_SNS = OV_SNS = 0V

3

Maximum Lamp Run Frequency

250

262

KHz

Lamp Run Frequency

63

65

67

KHz

Lamp Run Frequency

Lamp is ignited, I_R = 80.6K

61

65

69

KHz

Lamp Run Frequency Regulation over

0.1

%

Internal Digital Dimming

Burst Frequency

127

Hz

PWM BLOCK

Error Amp Transconductance

60

150

µmho

Error Amp Output Source Current

100

µA

Error Amp Output Sink Current

100

µA

Error Amp Output High Voltage

BRITE_OUT – EA_IN = 50mV

2.5

2.9

V

Error Amp Output Low Voltage

EA_IN – BRITE_OUT = 50mV

0.015

0.5

V

Error Amp Input Offset Voltage

30

mV

Max Duty Cycle

47

%

Ramp Valley Voltage

100

mV

Ramp Peak Voltage

2.1

V

DD_CLK INPUT

Pull-up Resistance

50

KΩ

Input High Threshold

Conventional Dimming

1.6

2.0

V

Input Low Threshold

Reverse Dimming

0.4

0.9

V

Input High Current

DD_CLK = 5V; VDDP=5V

45

70

µA

Input Low Current

DD_CLK = 0V; VDDP=5V

-65

-100

µA

DIM_MODE INPUT

Low State

0.4

0.85

V

Floating State

1.2

1.35

1.8

V

High State

2.35

2.8

V

Input High Current

DIM_MODE = 5V

70

120

µA

Input Low Current

DIM_MODE = 0V

-25

-50

µA

ANALOG DIMMER BLOCK

BRITE_IN Input Current

-1

1

µA

BRITE_IN = 0V

0

25

60

mV

BRITE_IN > 2.05V

1.9

2.0

2.10

V

BRITE_ IN < 0V

1.9

2.0

2.1

V

Conventional Dimming

BRITE_OUT

BRITE_IN > 2.05V

0

25

60

mV