WS3410 ProductDescription Non-isolated Buck APFC Offline LED Driver Features Description Active PFC for High Power Factor and Low THD Critical Conduction Mode Operation System Efficiency up to 95% with active PFC, specially designed for universal input offline Without auxiliary winding constant current LED lighting. The driver with on-chip PFC Excellent Line and Load Regulation circuit achieves high power factor and low THD. Operating in ±3% LED Output Current Accuracy critical conduction mode, the power MOSFET switching loss Thermal Regulation Function is reduced and the inductor is fully utilized. LED Short/Open Protection Current Sensing Resistor Open Protection Auto Fault Recovery Available in SOT23-6 Package The WS3410 is a high precision non-isolated buck driver With few external components, the LED output current can be precisely controlled. The WS3410 offers rich protection functions to improve the system reliability, including LED open circuit protection, LED short circuit protection, CS resistor open circuit protection and cycle by cycle current limit. All the protection Applications functions are auto-recovery. The system reliability is further E27 LED Bulb, Spot Light improved by the thermal regulation function. The output PAR30, PAR38 Lamp current is reduced when the driver is over temperature. T8/T10 LED String Other LED Lighting The WS3410 has ultra low start up current and ultra low operating current. The WS3410 is available in SOT23-6 Package Typical Application WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS Copyright@WinsemiMicroelectronics Co.,Ltd.,All rightreserved WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS 1030 WS3410 ProductDescription Pin Configuration and Marking Information The WS3410 is available in SOT23-6 Package，the top marking is shown as below: 3410：Product Code X：Product Code YM：Production Date XX：Internal Code For QC Pin Definition Name Pin No. Description VCC 1 Power Supply Pin. Connect a bypass capacitor from this pin to GND. GND 2 Ground. COMP 3 GATE 4 Gate Driver Pin. Connect this pin to the gate of external power MOSFET. CS 5 Current Sense Pin. Connect a resistor to GND to sense the inductor current. FB 6 Loop Compensation Node. This pin connects a capacitor to GND for stabilization of the control loop, achieving accurate LED current, high Power Factor and low THD. Feedback Voltage Input Pin. This pin detects the inductor demagnetization signal and the output voltage. Internal Block Diagram WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS www.winsemi.com Tel : +86-755-8250 6288 WINSEMI MICROELECTRONICS Fax : +86-755-8250 6299 WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS 2/8 WS3410 ProductDescription Ordering Information Package 6-Pin SOT23-6, Pb-free Marking Part Number WS3410YP WS3410YP Recommended Operation Conditions Part Number Package WS3410YP SOT23-6 Input voltage Maximum output power 175VAC-264VAC 120V/450mA 90VAC-264VAC 80V/450mA Absolute Maximum Ratings symbol paramete Range unit VCC Vcc pin voltage -0.3~8 V Vgate Gate driver pin voltage -0.3~8 V VCS Current sense pin input voltage -0.3~7 V VFB Feedback pin input voltage -0.3~7 V VCOMP Compensation pin voltage -0.3~7 V PDMAX Power dissipation 0.2 W TJ Operating junction temperature 165 ℃ TSTG Storage temperature range -55~165 ℃ Note : Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS www.winsemi.com Tel : +86-755-8250 6288 WINSEMI MICROELECTRONICS Fax : +86-755-8250 6299 WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS 3/8 WS3410 ProductDescription Electrical Characteristics (Unless otherwise specified, VCC=8V and TA =25 ℃) Symbol Parameter Conditions Min Typ Max 7.5 8.0 8.5 Units Supply Voltage Section Vcc_clamp VCC Clamp Voltage Icc_clamp VCC Clamp Current VCC_ST VCC Turn On Threshold VCC Rising Vuvlo_HYS VCC Turn Off hysteresis VCC Falling 1.32 Ist VCC Startup Current VCC<VCC_ST-0.5V 70 Iop VCC Operating Current 5 7.07 V mA 7.57 8.07 V V 100 uA 400 uA 1 V 350 ns 200 ns Current Sense Section Over current Vocp TLEB Protectionthreshold Leading Edge Blanking Time for Current Sense Td Switch off Delay Time Compensation Section VREF Internal Reference Voltage 194 200 206 mV VCL COMP Low Clamp Voltage 1.5 V VCH COMP High Clamp Voltage 4 V Internal driver TOFF_MIN Minimum Off Time 3 us TON_MAX Maximum On Time 20 us 1.6 V 0.2 V Feedback Section VFB VZCD FB Over Voltage Protection Threshold FB Falling Edge Threshold Voltage Thermal Regulation Section TREG WINSEMI Thermal Regulation Temperature MICROELECTRONICS WINSEMI MICROELECTRONICS www.winsemi.com Tel : +86-755-8250 6288 ℃ 150 WINSEMI MICROELECTRONICS Fax : +86-755-8250 6299 WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS 4/8 WS3410 ProductDescription Application Information RFBL 1.6V RFBL RFBH VOVP The WS3410 is a high precision Active PFC driver, specially designed for non-isolated buck offline constant current LED lighting. Operating in critical conduction mode, Where, the driver achieves high power factor, low THD and high RFBL: The lower resistor of the feedback network efficiency. RFBH: The upper resistor of the feedback network VOVP: Output over voltage setting point Start Up The minimum VOVP should be set about 1.3Vo.It is After system powered up, the VCC pin capacitor is charged up by the start up resistor. When the VCC pin recommended that the FB lower resistor is set to 3.3KΩ—5.1KΩparalleled with a 22pF ceramic capacitor. voltage reaches the turn on threshold, the internal circuits start working. The COMP pin voltage is pulled up to 1.5V Protection Functions quickly. Then the WS3410 starts switching. The system works at 10k Hz frequency at the beginning, the COMP The WS3410 offers rich protection functions to improve the system reliability. voltage rises up gradually, and the inductor peak current When the LED is open circuit, the output voltage will also rises up. The LED current hence achieves a soft start gradually rise up. The output voltage is sensed by the FB pin without overshoot. After the output voltage is built up, the when power MOSFET is turned off. When FB voltage VCC power is supplied by the output voltage through a reaches the OVP threshold, it will trigger fault logic and the diode. system stops switching. The maximum value of the startup current is 100uA. For When the LED is shorted circuit, the system will work the application of 85VAC—264VAC, the startup resistor can under 10k Hz switching frequency. Meanwhile, the output be calculated by the equation: voltage is low and the VCC pin cannot be charged up by the Rst Vin _ min I st _ max output voltage, so the VCC pin voltage will gradually 85V 850 KΩ 100uA decrease and finally reaches the UVLO threshold. After the system enters into fault condition, the VCC voltage will decrease until it reaches UVLO threshold. Then the system will re-start again. If the fault condition is Constant Current Control The WS3410 utilizes floating ground structure. The removed, the system will resume normal operation. inductor current is sensed during the whole switching cycle, When the output is short circuit or the inductor is thus it achieves high precision output current control and saturated, the CS peak voltage will be relatively high. When also excellent line and load regulation. CS voltage reaches the internal limitation (1V), the power The current in LED can be calculated by the equation: MOSFET will be turned off instantaneously. This cycle by cycle current limitation can help protecting the power V 200mV I O CS RCS Rcs MOSFET, the inductor and the output diode. Thermal Regulation Rcs is the current sensing resistor. The WS3410 integrates thermal regulation function. When the system is over temperature, the output current is Feedback Network gradually reduced; the output power and thermal dissipation The WS3410 senses the output current zero crossing information through the feedback network, the FB falling threshold voltage is set to 0.2V with 0.15V hysteresis. The are also reduced. The system temperature is regulated and the system reliability is improved. The thermal regulation temperature is set to 150℃ internally. FB pin is also used to detect output OVP, the threshold voltage is 1.6V. The ratio of FB upper resistor to lower resistor can be set as: PCB Layouts The following guidelines should be followed in WS3410 PCB layout: WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS www.winsemi.com Tel : +86-755-8250 6288 WINSEMI MICROELECTRONICS Fax : +86-755-8250 6299 WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS 5/8 WS3410 ProductDescription Bypass Capacitor FB Pin The bypass capacitor on VCC pin should be as close as The feedback resistor divider should be as close as possible to the VCC and GND pins. possible to the FB pin, and the trace must keeps away from Ground Path dynamic node of the inductor (DRAIN pin trace、the positive The power ground path for current sense resistor pin and the negative pin of Vo trace), otherwise the FB pin should be short and wide, and it should be as close as OVP function might have risk to be mis-triggered by the possible to the IC ground (pin 2), otherwise the LED output system noise. current accuracy maybe affected. The IC signal ground for DRAIN Pin COMP and FB components should be connected to the IC To increase the copper area of DRAIN pin for better GND pin with short traces and should be away from the thermal dissipation. However, too large copper area may power ground path. compromise EMI performance. The Area of Power Loop The material of PCB The area of main current loop should be as small as Avoid choosing the material that is easy to absorb the possible to reduce EMI radiation. WINSEMI MICROELECTRONICS WINSEMI moisture, just like paper copper-clad laminates. MICROELECTRONICS www.winsemi.com Tel : +86-755-8250 6288 WINSEMI MICROELECTRONICS Fax : +86-755-8250 6299 WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS 6/8 WS3410 ProductDescription Package Information SOT23-6Package Outline Dimensions Unit:mm A C2 B1 B θ1 θ B2 A2 R θ3 C D R1 θ2 C1 R2 D1 D3 D2 A1 Winsemi Symbol Dimensions in Millimeters Dimensions in Inches Min Max Min Max A 2.72 3.12 0.107 0.123 B 1.40 1.80 0.055 0.071 C 1.00 1.20 0.039 0.047 A1 0.90 1.00 0.035 0.039 A2 0.30 0.50 0.012 0.020 B1 2.60 3.00 0.102 0.118 B2 0.119 0.135 0.005 0.005 C1 0.03 0.15 0.001 0.006 C2 0.55 0.75 0.022 0.030 D 0.03 0.13 0.001 0.005 D1 0.30 0.60 0.012 0.024 D2 D3 WINSEMI MICROELECTRONICS 0.25TYP 0.01TYP 0.60 WINSEMI 0.70 MICROELECTRONICS www.winsemi.com Tel : +86-755-8250 6288 WINSEMI MICROELECTRONICS Fax : +86-755-8250 6299 0.024 WINSEMI MICROELECTRONICS 0.028 WINSEMI MICROELECTRONICS 7/8 WS3410 ProductDescription NOTE: 1.We strongly recommend customers check carefully on the trademark when buying our product, if there is any question, please don't be hesitate to contact us. 2.Please do not exceed the absolute maximum ratings of the device when circuit designing. 3.Winsemi Microelectronics Co., Ltd reserved the right to make changes in this specification sheet and is subject to change without prior notice. CONTACT: Winsemi Microelectronics Co., Ltd. ADD:Futian District, ShenZhen Tian An Cyber Tech Plaza two East Wing 1002 Post Code : 518040 Tel : +86-755-8250 6288 FAX : +86-755-8250 6299 Web Site : www.winsemi.com WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS www.winsemi.com Tel : +86-755-8250 6288 WINSEMI MICROELECTRONICS Fax : +86-755-8250 6299 WINSEMI MICROELECTRONICS WINSEMI MICROELECTRONICS 8/8