StarChips Technology SCT2004 4-channel Constant Current Driver for LEDs Features Current regulated output channels, c onstant current range: 20 320 mA Constant current source invariant to load voltage change Fast output current control, the minimum output enable pulse width = 80 ns Excellent output current matching channel to channel : + 3% chip to chip : + 6% All output current are adjusted through one external resistor . Dimming control available Built-in thermal protection function . Supply voltage range: 5V . Package: SOP8 (with/without heat sink pad optional) Product Description SCT2004 is a four channels constant current driver for the LED lighting. It can provide the finest PWM control effect with its ability to sink constant current from LED clusters with minimum pulse width only 80 ns. The PWM control is performed by connecting the PWM signal from system control unit to OE pin of SCT2004. The full scale current value of each output is set by an external resistor connected to REXT pin. The SCT2004 guarantees to endure maximum DC 17V at each output port. Each output of SCT2004 can sink a constant current up to 320mA. In fields of high power LED lighting applications, we can simply shunt the outputs to get higher current driver-ability. The excellent current regulation capability let SCT2004 easily drive each output current to a constant stable status nearly without affecting by power supply of LED, loading due to variant VF of LEDs and operating temperature. Besides, with built-in thermal protection function, the SCT2004 stop driving the output while sense its junction temperature exceeds the 160 high limit and the output will be turn on again while the junction temperature is below the 130 low limit. Thus the driver system is protected from damage of overheat. StarChips Technology, Inc. 4F, No.5, Technology Rd., Science-Based Industrial Park, Hsin-Chu, Taiwan, R.O.C TEL: 03-577-5767 FAX: 03-577-6575 E-mail: contact starchips.com.tw SCT2004 Block Diagram Pin Configuration OUT1 OUT4 OUT2 OUT3 GND VDD 8 1 OE 2 7 REXT OUT1 6 OUT4 3 REXT Current 5 OUT2 4 OUT3 Output Driver Regulator OE Terminal Description Pin No. Pin Name Function 1 GND Ground terminal. Input terminal of output enable signal. 2 OE Output is enabled when OE is high. 3~6 OUT1~4 Output terminals with constant current. Input terminal used to connect an external 7 REXT resistor for setting up all output current. 8 VDD Supply voltage terminal. Equivalent Circuits of Inputs (1) VDD VDD OE GND GND GND Ordering information Part Number Marking Package SCT2004CSOG 2004CSOG Pb free SOP8 with thermal pad(TP) SCT2004CSPG 2004CSPG Pb free SOP8 without thermal pad(TP) 2 StarChips 2007 V01-03