Datasheet DD311 (SiTI) - 6

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.
DD311
Tel：886-3-5645656 Fax：886-3-5645626
VL IREF RL Optional
REXT OUT
CLED Optional R
EN
C
VSS GND
CL
Switching Characteristics Test Circuit
Transient Characteristics
In order to reduce the overshoot or undershoot(Vout) during switching large current, it is recommended adding a large enough capacitor between VLED and GND to keep LED supply voltage(VLED) stable. The longer rise time and fall time of the EN dimming signal, adjustable by RC filter, produce the smooth transient response of output current. The two output waveforms illustrating the EN dimming signal with and without RC filter are given below: without RC filter with RC filter
HIGH CONSTANT CURRENT LED DRIVER Version:PRE.001
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