EEPROM-Programmable, High-Voltage, 350mA

LED Drivers with LED Current Foldback

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7

LED CURRENT FALL TIME (EXPANDED)

MAX16805 toc10

20

µs/div

2V/div

200mA/div

0V

0A

DIM PULSED AT

200Hz

LED CURRENT RISE TIME (EXPANDED)

MAX16805 toc11

20

µs/div

2V/div

200mA/div

0V

0A

DIM PULSED AT

200Hz

OUTPUT CURRENT DUTY CYCLE

vs. ANALOG DIM VOLTAGE

3

2

1

20

40

60

80

100

120

0

04

RAMP REGISTER = 0x07

CFD = GND

TFP = 5V

TFN = GND

OUTPUT CURRENT

DUTY CYCLE vs. INPUT VOLTAGE

INPUT VOLTAGE (V)

18

16

14

12

10

8

6

4

2

20

40

60

80

100

120

0

020

BIT3 = 1

BIT3 = 0

LED CURRENT

THRESHOLD REGISTER = (0x07)

OUTPUT CURRENT

DUTY CYCLE vs. INPUT VOLTAGE

INPUT VOLTAGE (V)

25

20

15

10

5

20

40

60

80

100

120

0

030

BIT3 = 1

BIT3 = 0

LED CURRENT

THRESHOLD REGISTER = (0x00)

OUTPUT CLAMP

vs. THERMAL FOLDBACK SLOPE

1.4

1.2

0.8

1.0

0.4

0.6

0.2

5

10

15

20

25

30

35

40

45

0

0

1.6

THERMAL SLOPE = 4V/V

THERMAL SLOPE = 4V/V

THERMAL SLOPE = 8V/V

THERMAL SLOPE = 12V/V

THERMAL FOLDBACK

CLAMP LEVEL = 40%

THERMAL

KNEE = +60

°C

OUTPUT RESPONSE TO SW INPUT

MAX16805 toc16

40ms/div

5V/div

200mV/div

DEBOUNCE

TIME

DEBOUNCE

TIME

Typical Operating Characteristics (continued)