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Electrical characteristics – Rainbow Electronics MAX8709 User Manual

Page 4

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MAX8709

High-Efficiency CCFL Backlight
Controller with SMBus Interface

4

_______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS

(Circuit of Figure 1. V

BATT

= 12V, V

LOT

= V

REF

, V

CC

= V

DD,

V

SUS

= 5.3V,

T

A

= -40°C to +85°C. Typical values are at T

A

= +25°C,

unless otherwise noted.) (Note 2)

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

V

CC

= V

DD

= V

BATT

4.6

5.5

V

BATT

Input Voltage Range

V

CC

= V

DD

= open

5.5

28.0

V

V

BATT

= 28V

3

V

BATT

Quiescent Current

V

SUS

= 5.5V

V

BATT

= V

CC

= 5V

3

mA

V

BATT

Quiescent Current, Shutdown

SUS = GND

20

µA

V

CC

Output Voltage, Normal Operation

V

SUS

= 5.5V, 6V < V

BATT

< 28V,

0 < I

LOAD

< 20mA

5.0

5.5

V

V

CC

Output Voltage, Shutdown

SUS = GND, no load

3.5

5.5

V

V

CC

rising (leaving lockout)

4.5

V

CC

Undervoltage-Lockout Threshold

V

CC

falling (entering lockout)

4.0

V

V

CC

Power-On Reset (POR) Threshold

Rising edge

0.90

2.70

V

REF Output Voltage, Normal Operation

4.5V < V

CC

< 5.5V, I

LOAD

= 40µA

1.95

2.05

V

GH1, GH2, GL1, GL2 On-Resistance

I

TEST

= 100mA, V

CC

= V

DD

= 5.3V

18

BST1, BST2 Leakage Current

V

BST

_ = 12V, V

LX

_ = 7V

5

µA

Input Resonant Frequency

Guaranteed by design

25

300

kHz

Minimum Off-Time

180

380

ns

Maximum Off-Time

18

38

µs

Current-Limit Threshold
LX1 - GND, LX2 - GND (Fixed)

ILIM = V

CC

180

220

mV

V

ILIM

= 0.5V

80

120

Current-Limit Threshold
LX1 - GND, LX2 - GND (Adjustable)

V

ILIM

= 2.0V

370

430

mV

Current-Limit Leading-Edge Blanking

250

450

ns

LOT Input Voltage Range

0.5

V

REF

V

LOT Input Bias Current

-2

+2

µA

IFB Input Voltage Range

-1.7

+1.7

V

IFB Regulation Point

380

420

mV

IFB Input Bias Current

V

IFB

= 0.4V

-2

+2

µA

IFB Lamp-Out Threshold

LOT = REF

500

700

mV

ISEC Input Voltage Range

-2

+2

V

ISEC Regulation Point

1.20

1.30

V

ISEC Input Bias Current

V

ISEC

= 1.25V

-2

+2

µA

VFB Input Voltage Range

-2

+2

V

VFB Input Bias Current

V

VFB

= 0.5V

-0.5

+0.5

µA

VFB Regulation Point

490

530

mV

VFB Zero-Voltage Crossing Threshold

-10

+10

mV

Digital PWM Chopping Frequency

200

220

Hz