StarChips Technology SCT2168 V01 01 May/09 8-bit Serial-In/Parallel-Out Constant Current Driver Product Description The SCT2168 serial-interfaced LED driver sinks 8 LED clusters with constant current to keep the uniform intensity of LED displays. In applications, an external resistor is used to set the full-scale constant output current from 5mA up to 120mA. The SCT2168 guarantees each output can endure maximum 17V DC voltage stress. The built-in shift registers and data latches making the SCT2168 effective solution in driving LED display. The output enable function gates all 8 outputs on and off, and is fast enough to be used as PWM input for LED intensity control. Since the serial data input rate can be reached up to 25MHz, the SCT2168 will satisfy system which needs high volume data transmission to control the LED display. Features 8 constant current sinker with LED power-supply voltage up to 17V Constant output current : 5 120mA 5V, 3 80mA 3.3V Excellent current regulation to load, supply voltage and temperature 1% Current matching between outputs 3% Current matching between ICs Fast output current control: Minimum PWM pulse width = 120ns All output current are programmed together using a single external resistor CMOS Schmitt trigger inputs with clock rate up to 25MHz Operating supply voltage range of 3.3V to 5.5V Built-in power on reset circuit forces all the outputs off while power on Built-in thermal protection function to prevent damage from over current operation Gradually 2ns delayed outputs to lower output switching noise Package: SOP16, SSOP16,SOP16W Applications: LED Displays, Variable Message Signs, LED Traffic Signs Selector Guide Number of Max Output Min PWM Pulse Supply Part Outputs Current (mA) Width (ns) Voltage (V) SCT2110 8 180 100 5 SCT2167 8 60 180 3.3/5 SCT2168 8 120 120 3.3/5 SCT2210 16 120 50 5 SCT2026 16 90 120 5 SCT2024 16 60 180 3.3/5 StarChips Technology, Inc. 4F, No.5, Technology Rd., Science-Based Industrial Park, Hsin-Chu, Taiwan, R.O.C TEL: +886-3-577-5767 555 FAX: +886-3-577-6575 E-mail: service starchips.com.tw Page 1 of 15 8-bit Serial-In/Parallel-Out Constant-Current LED Driver SCT2168 Block Diagram OUT6 OUT7 OUT0 OUT1 Current Output Driver REXT Regulator OE/ Q Q Q Q ST D ST D ST D ST D LA/ Q D Q D D Q D Q SDI SDO C C C C CLK Pin Configuration Ordering information GND 1 VDD 16 REXT SDI 2 15 Part Number Package CLK 3 SDO 14 SCT2168 13 OE/ SCT2168CSOG Green SOP16 LA/ 4 CSOG 5 OUT7 OUT0 12 CSSG SCT2168CSSG Green SSOP16 OUT1 6 11 OUT6 CSWG OUT5 OUT2 7 10 SCT2168CSWG Green SOP16W OUT4 8 9 OUT3 Terminal Description Pin No. Pin Name Function 1 GND Ground terminal. 2 SDI Serial input terminal of data shift register. Clock input terminal of shift register, data is 3 CLK sampled at the rising edge of CLK. Data is latched when LA/ is low. Data on shift 4 LA/ register goes through when LA/ is high. 5 ~ 12 OUT0 ~ OUT7 Output terminals with constant current. Input terminal of output enable signal. Output is 13 OE/ enabled when OE/ is low. Output terminal of serial-data output to the SDI 14 SDO of next SCT2168. Input terminal used to connect an external 15 REXT resistor for setting up all output current. 16 VDD Supply voltage terminal. Page 2 of 15