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Wide brightness range ccfl backlight controllers, Typical operating characteristics (continued) – Rainbow Electronics MAX1839 User Manual

Page 7

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MAX1739/MAX1839

Wide Brightness Range

CCFL Backlight Controllers

_______________________________________________________________________________________

7

Typical Operating Characteristics (continued)

(V

IN

= 12V, V

CTL

= V

CRF

, V

MINDAC

= 1V, MODE = GND, Circuit of Figure 8.)

20ms/div

STARTUP

(ADC SOFT-START, MODE = GND)

V

CTAP

10V/div

V

BATT

V

CSAV

500mV/div

I

BATT

500mA/div

MAX1739/1839 toc09

12V

0

2ms/div

LAMP-OUT VOLTAGE LIMITING

V

SECONDARY

2kV/div

V

CTAP

5V/div

MAX1739/1839 toc10

1ms/div

SYNCHRONIZED DPWM

(f

MODE

= 100kHz, V

CTL

= V

CRF

/2)

V

CSAV

500mV/div

V

CTAP

5V/div

V

DH

20V/div

MAX1739/1839 toc07

1ms/div

SYNCHRONIZED DPWM

(f

MODE

= 32kHz, V

CTL

= V

CRF

/2)

V

CSAV

500mV/div

V

CTAP

5V/div

V

DH

20V/div

MAX1739/1839 toc06

400ms/div

LAMP-OUT VOLTAGE LIMITING

V

SECONDARY

2kV/div

V

CTAP

5V/div

MAX1739/1839 toc11

0

200

100

500

400

300

800

700

600

900

0

10

5

15

20

25

INPUT CURRENT vs.

INPUT VOLTAGE

MAX1739/1839 toc12

V

BATT

(V)

I

BATT

(mA)

0

2

1

5

4

3

8

7

6

9

SHUTDOWN CURRENT (

µ

A)

SHUTDOWN

MINIMUM BRIGHTNESS

MAXIMUM BRIGHTNESS