DD231 Version : A.001 Issue Date : 2004/6/1 File Name : SP-DD231-A.001.doc Total Pages : 7 3-CHANNEL CONSTANT CURRENT LED DRIVERS 新竹市科學園區展業一路 9 號 7 樓之 1 SILICON TOUCH TECHNOLOGY INC. 9-7F-1, Prosperity Road I, Science Based Industrial Park, Hsin-Chu, Taiwan 300, R.O.C. Fax：886-3-5645626 Tel：886-3-5645656 點晶科技股份有限公司 SILICON TOUCH TECHNOLOGY INC. DD231 DD231 3-CHANNEL CONSTANT CURRENT LED DRIVERS DESCRIPTION The DD231 is a 3-channel constant current LED driver. It’s designed to operate as a constant-current sink to drive the LEDs with an external resistance in low power environment. Because the DD231 directly determines output current by each channel in low Bit-to-Bit skew, it is ideal for driving LED whose light intensity is proportional to the current passing through them, not the voltage across their terminals. This configuration eliminates the need of external capacitors and inductances. With an input voltage range of 3V to 5V, so the device can work in general battery system. The value of constant current can be varied using an external resistor (Iout = 5 ~30mA). GENERAL FEATURES ˙Constant Current Output, 5~30mA. ˙Supply Voltage VDD is 3V to 5V. ˙Bit-to-Bit : ± 3.0% (Max) @ IOUT = 5 ~ 30mA. ˙Only Need One External Resistor, No Other External Parts. ˙Small 6-Pin SOT26 Package. APPLICATIONS ˙White LED Display Backlighting ˙Cellular Telephones ˙Handheld Computers ˙Digital Cameras ˙Portable MP3 Players ˙Pagers ˙Personal Digital Assistant ˙E-Books and Sub Notebooks 3-CHANNEL CONSTANT CURRENT LED DRIVERS Version: A.001 Page 1 點晶科技股份有限公司 SILICON TOUCH TECHNOLOGY INC. DD231 Pin Description PIN NAME VDD Rext GND Out0 to Out2 Out0 Rext Out1 GND Out2 VDD DESCRIPTION Power supply terminal Input terminal of an external resistor Ground terminal Output terminal Maximum Ratings (Ta = 25°°C, Tj(max) = 140°°C) CHARACTERISTIC Supply Voltage Output Current Output Voltage GND Terminal Current SYMBOL RATING UNIT VDD IOUT VOUT IGND V mA V mA °C Power Dissipation PD Operating Temperature Top 7 30 ~17 90 0.35 -20 ~ 85 Storage Temperature Tstg -55 ~ 150 W °C Recommended Operating Condition CHARACTERISTIC Supply Voltage Output Voltage Output Current Operating temperature SYMBOL VDD VOUT IO TOPR CONDITION Outn 3-CHANNEL CONSTANT CURRENT LED DRIVERS MIN. 2.7 0.2 5 -20 Version: A.001 TYP. 3.3 0.6 MAX. 6 5.0 30 85 Page UNIT V V mA °C 2 點晶科技股份有限公司 SILICON TOUCH TECHNOLOGY INC. Electrical Characteristics CHARACTERISTIC (Typ:VDD = 3.3 V, Ta = 25°°C unless otherwise noted) SYMBOL CONDITION MIN. TYP. MAX. UNIT ±1.5 ±3 % ±1.5 ±3 VOUT = 1 V IOL1 REXT = 12kΩ Output Current (Bit-Bit) VOUT = 0.5 IOL2 Output Current (Chip-Chip) DD231 REXT = 60kΩ % IOL3 VOUT = 1.0V, REXT = 12kΩ 26.3 29.2 32.1 mA IOL4 VOUT = 0.5V, REXT = 60kΩ 4.8 5.31 5.8 mA Detailed Description 1) Constant Current Output Value Setting The output current is determined by the resistance connected between REXT pin and GND. The approximate relation between the resistance value and the base current value is shown in Fig1, the approximate equation presented in (Eq.1). Iout-Rext 35.00 30.00 Iout0 (mA) 25.00 20.00 15.00 10.00 5.00 0.00 0 10 20 30 40 50 60 70 80 Rext (kΩ) Fig 1 Iout ≅ 350.4/Rext (Eq.1) 2) Constant Current Output Value and Output Voltage In order to obtain a good constant current output, a suitable output voltage is necessary. Users can get related information about the minimum output voltage from Fig 2. 3-CHANNEL CONSTANT CURRENT LED DRIVERS Version: A.001 Page 3 點晶科技股份有限公司 SILICON TOUCH TECHNOLOGY INC. DD231 35.00 30.00 Iout0 (mA) 25.00 20.00 15.00 10.00 5.00 0.00 0 1 2 3 4 5 6 Vout (V) Fig 2 TYPICAL APPLICATION Rext VDD Out0 Rext Out1 Out2 1 2 3 5 6 GND 4 VDD Fig 3 3-CHANNEL CONSTANT CURRENT LED DRIVERS Version: A.001 Page 4 點晶科技股份有限公司 SILICON TOUCH TECHNOLOGY INC. DD231 DIE CONFIGURATION (UNIT: μM) Die Size: 984.3X643.8 Die Thickness: 300 Pad Size: 80X80 Pin NO. PAD Name 1 Out0 2 Out1 3 Out2 4 Rext 5 GND 6 VDD 3-CHANNEL CONSTANT CURRENT LED DRIVERS Center Coordinate (X,Y) 80.5 564.1 202.1 564.1 323.7 564.1 581.3 391.5 586.5 224.9 913.9 419.25 Version: A.001 Page 5 點晶科技股份有限公司 SILICON TOUCH TECHNOLOGY INC. DD231 Package Outline (SOT26) (6-pin SOT-26 ) C E H L e θ1 D A2 A A1 b SYMBOL Dimensions in Millimeters MIN NOM A A1 1.00 0.00 1.10 － MAX 1.30 0.10 A2 b C D E e 0.70 0.35 0.10 2.70 1.40 － 0.80 0.40 0.15 2.90 1.60 1.90(TYP) 0.90 0.50 0.25 3.10 1.90 － H L 2.60 0.37 2.80 － 3.00 － θ1 1° 5° 9° The products listed herein are designed for ordinary electronic applications, such as electrical appliances, audio-visual equipment, communications devices and so on. Hence, it is advisable that the devices should not be used in medical instruments, surgical implants, aerospace machinery, nuclear power control systems, disaster/crime-prevention equipment and the like. Misusing those products may directly or indirectly endanger human life, or cause injury and property loss. Silicon Touch Technology, Inc. will not take any responsibilities regarding the misusage of the products mentioned above. Anyone who purchases any products described herein with the above-mentioned intention or with such misused applications should accept full responsibility and indemnify. Silicon Touch Technology, Inc. and its distributors and all their officers and employees shall defend jointly and severally against any and all claims and litigation and all damages, cost and expenses associated with such intention and manipulation. 3-CHANNEL CONSTANT CURRENT LED DRIVERS Version: A.001 Page 6