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Typical operating characteristics, Electrical characteristics (continued) – Rainbow Electronics MAX16831 User Manual

Page 5

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MAX16831

High-Voltage, High-Power LED Driver with

Analog and PWM Dimming Control

_______________________________________________________________________________________

5

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

THERMAL SHUTDOWN

Thermal Shutdown Temperature

T

SHDN

Temperature rising

+165

°C

Hysteresis

∆T

SHDN

20

°C

ELECTRICAL CHARACTERISTICS (continued)

(V

CC

= V

UVEN

= 14V, C

REG1

= 1µF, C

REG2

= 1µF, C

CLMP

= 0.1µF, R

T

= 25kΩ, T

A

= T

J

= -40°C to +125°C, unless otherwise noted.

Typical specifications are at T

A

= +25°C.)

Note 1: Dropout voltage is defined as the input to output differential voltage at which the regulator output voltage drops 100mV below

the nominal output voltage.

Note 2: V

CLMPTH

determines the voltage required to operate the current-sense amplifier. The DIM driver requires 2.5V for (V

CLMP

- V

LO

)

to drive the external MOSFET. V

HI

is typically one diode drop above V

CLMP

. A large capacitor connected to V

CLMP

slows the

response of the LED current-sense circuitry, resulting in current overshoot. To ensure proper operation, connect a 0.1µF
capacitor from CLMP to LO.

Typical Operating Characteristics

(V

CC

= V

UVEN

= 14V, C

REG1

= 1µF, C

REG2

= 10µF, C

CLMP

= 0.1µF, R

T

= 25kΩ, R

CS

= 0.1Ω, T

A

= +25°C, unless otherwise noted.)

18

20

19

22

21

24

23

25

27

26

28

-60

-20

0

20

-40

40 60 80

120

100

140

SHUTDOWN CURRENT

vs. TEMPERATURE

MAX16831 toc01

TEMPERATURE (

°C)

SHUTDOWN CURRENT (

µ

A)

2.0

2.2

2.1

2.4

2.3

2.6

2.5

2.7

2.9

2.8

3.0

-60

-20

0

20

-40

40 60 80

120

100

140

OPERATING CURRENT

vs. TEMPERATURE

MAX16831 toc02

TEMPERATURE (

°C)

OPERATING CURRENT (mA)

DGT AND DRV NOT
SWITCHING

40

30

20

10

0

70

60

50

80

90

110

100

120

0

10

20

30

40

VOLTAGE ACROSS LED CURRENT-SENSE

RESISTOR vs. SUPPLY VOLTAGE

MAX16831 toc03

SUPPLY VOLTAGE (V)

VOLTAGE ACROSS R

CS

(mV)