IS31LT3918

Integrated Silicon Solution, Inc. – www.issi.com

Rev. A, 09/01/2011

3

ABSOLUTE MAXIMUM RATINGS

Parameter

Range

Unit

Vin pin to GND

-0.3 – 6.0

V

DIM1,DIM2,CS, ADJ, GATE, Toff pin to GND

-0.3 - 6.0

V

Vin pin input current (Note1)

10

mA

Junction temperature

-40 – 150

℃

Device storage temperature

-65 - 150

℃

ESD（Human Body model）

3500

V

Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and

functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not

implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

(The specifications are at TA=25°C and VINDC=10V (Note 2), RIN =10K, unless otherwise noted)

Symbol

Parameter

Conditions

Min

Typ

Max

Unit

Vin PIN clamp voltage

Supply voltage connected to

Vin via an appropriate resistor

4.3

5

5.5

V

UVLO

Undervoltage lockout

Vin rising

4.8

V

△

UVLO

UVLO hysteresis

400

mV

Quiescent Current

Vin=5V

300

400

uA

Input current in UVLO

Vin=4V

90

120

uA

Current sense threshold

ADJ=5V

245

250

255

mV

Current sense blanking time

445

500

650

ns

Off time

9.8

10

10.2

us

(Note 3)

PWM input voltage high threshold

2.5

V

PWM input voltage low threshold

0.25

0.5

0.75

V

Linear dimming input voltage range

0.5

2.5

V

GATE source current

GATE=0

75

90

mA

GATE sink current

GATE=5V

75

90

mA

Over temperature protection threshold

150

△

Over temperature protection hysteresis

20

Over current protection CS voltage

threshold

ADJ=5V,CS rising

0.35

0.4

0.45

V

Over current protection Toff delay time

500

us

Maximum switch off time for switch

dimming

2

s

Notes:

1. Beyond the input current range, Vin pin may not clamp at 5V.

2. VIN is the input voltage. When VIN>5V, input voltage connected to Vin pin should via a appropriate resistor.