點晶科技股份有限公司

SILICON TOUCH TECHNOLOGY INC

.

新竹市科學園區展業一路9號7樓之1

9-7F-1, Prosperity RoadⅠ, Hsin-Chu, Taiwan, R.O.C.

Tel：886-3-5645656

Fax：886-3-5645626

3-CHANNEL CONSTANT CURRENT LED DRIVERS

Version:A.002

Page 12

DM413

Power Dissipation

Notice that the power dissipation of a semiconductor chip is limited to its package and ambient

temperature, in which the device requires the maximum output current calculated for given

operating conditions. The maximum allowable power consumption can be calculated by the

following equation:

Pd(max)(Watt) =

The relationship between power dissipation and operating temperature can be refer to the figure

below:

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0

20

40

60

80

100

120

140

160

Ambient Temperature Ta(°C)

Based on the Pd(max), the maximum allowable voltage of output terminal can be determined by the

following equation:

Tj(max)=140

°C

°C/Watt

°C/Watt

SOP16

SSOP16