L4120

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

3 of 4

www.unisonic.com.tw

QW-R125-031.C



ABSOLUTE MAXIMUM RATING

PARAMETER

SYMBOL

RATINGS

UNIT

Input Voltage

-0.3~+40

V

V

V

LX Output Voltage

-0.3~+40

V

Adjust Pin Input Voltage

-0.3~+6

V

Switch Output Current

1.5

A

Power Dissipation

0.5

W

Junction Temperature

150

°C

Operating Temperature

-40~105

°C

Storage Temperature

-55~150

°C

Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged.

Absolute maximum ratings are stress ratings only and functional device operation is not implied.



THERMAL DATA

PARAMETER

SYMBOL

RATINGS

UNIT

Junction to Ambient

180

°C/W



PARAMETER

SYMBOL

TEST CONDITIONS

MIN

TYP

MAX

UNIT

Input Voltage

6

40

V

Quiescent Supply Current with Output Off

ADJ Pin Grounded

400

μA

Quiescent Supply Current with Output

Switching

ADJ Pin Floating

1000

μA

Mean Current Sense Threshold Voltage

115

mV

Sense Threshold Hysteresis

±15

%

External Control Voltage Range On ADJ Pin

for DC Brightness Control

0.3

1.2

V

DC Voltage On ADJ Pin to Switch Chip from

Active (On) State to Quiescent (Off) State

0.15

0.2

0.25

V

DC Voltage On ADJ Pin to Switch Chip from

Quiescent (Off) State to Active (On) State

0.2

0.25

0.3

V

500

KΩ

Continuous LX Switch Current

1.2

A

LX Switch “On” Resistance

0.4

Ω

LX Switch Leakage Current

1

μA

Minimum Switch “ON” Time

200

ns

Minimum Switch “OFF” Time

200

ns

Typical Dimming Ratio

Ddim

L=27μH

1200:1

Recommended Maximum Operating

Frequency

1

MHz

Recommended Duty Cycle Range of Output

0.3

0.7

0.9

Internal Comparator Propagation Delay

50

ns

Thermal Shutdown Temperature

150

°C

Thermal Shutdown Hysteresis

20

°C

Note: Production testing of the chip is performed at 25°C. Functional operation of the chip and parameters specified

are guaranteed by design, characterization and process control in other temperature.