Single Feedback High Current DC-DC. 6 pins / Low Cost / High Current and Performance / Low Cost DC-DC Boost. from 2.8 Volt Up to 30 Volt

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1 Single Feedback High Current DC-DC 6 pins / Low Cost / High Current and Performance / Low Cost DC-DC Boost DESCRIPTION from 2.8 Volt Up to 30 Volt is a DC-DC boost converter that provides an accurate constant current designed for driving high-current loading. Operation at a fixed switching frequency of 1MHz allows the device to be used with small value external ceramic capacitors and inductor. A high current loading connected in series are driven with a regulated current set by the external resistor. The device also built-in Overload Protection to prevent operating fails condition. FEATURE Input voltage range: 2.8 to 30V Drives high current loading up to 30V Switch current limit 2 Ampere 1MHz fixed frequency minimizes the external components. Current Control with 100Hz~100kHz frequency signal input to EN/PWM pin. Internal soft-start limits the inrush current. Open/short circuit protection. SOT23-6 Package with RoHS Compliant and Halogen Free. APPLICATION High Current Loading for High Current Driving LEDs Backlight Vibration Motor BLOCK DIAGRAM Figure 1. All Right Reserved Akustik Inc. 1/9 Revision

2 PACKAGE OUTLINE SOT-23-6 IN OVP EN/PWM A θ M Dimension in mm Dimension in inch Symbol MIN. MAX. MIN. MAX. A J XXXX YWWP B B C D F LX GND SENSE F H H I C J I M D θ Marking (Top View) Package Type A B C D SOT mm 0.1 mm 0.35 mm 0.2 mm Marking Meaning Line Part Number Line 2 YWWP Date code : Y = Year WW = Week RECOMMONDED APPLICATION CIRCUIT Figure 2. All Right Reserved Akustik Inc. 2/9 Revision

3 APPLICATION GUIDE LINE LX PIN Step-up Regulator N-MOS Drain. Connect LX to inductor and diode. Place the components as close to LX as possible. SENSE PIN Sense pin. Connect a resistor R SENSE between SENSE and GND to set the output current: I OUT =0.1V/R SENSE. In order to have accurate current, precision resistors are preferred (1% recommended). EN/PWM PIN Enable and current control: (1). As enable input: Pull high more than 1.5V to turn on IC. (2). As current control input: Enter the square wave to start current control. The recommend control frequency is 100Hz~100KHz. OVP PIN Over Voltage Protection. The typical value is 30V. IN PIN Input Pin. Connect IN to the input voltage source. Decouple IN to GND pin with a capacitor sitting as close to IN as possible. Input voltage range is 2.8V~30V. Inductor Selection A 4.7uH inductor is recommended for. Small size, low core losses at 1MHz and low DCR are major concerns. Capacitor Selection The small size of ceramic capacitors will be ideal for. A 0.47uF output capacitor is recommended. Diode Selection Schottky diode is an ideal choice because of the low forward voltage drop and the fast reverse recovery. The SS14 is chosen as the reference component. The circuit is shown in Figure 3. Figure 3. Current Control There are three methods of current control: PWM current control (figure 4), Linear current control by filtered PWM (figure 5), Linear current control by voltage source (figure 6) All Right Reserved Akustik Inc. 3/9 Revision

4 Figure 4 PWM Current Control Figure 5 Linear Current Control by filtered PWM Figure 6 Linear Current Control by voltage LAYOUT RECOMMANDATION To avoid any noise problem or duty cycle abnormal caused by high peak currents and switching frequencies, the layout is very important during system design. 1. The input capacitor should be placed closed to the IN and the GND. Connecting the capacitor with IN and GND pins by short and wide tracks without using any vias for filtering and minimizing the input voltage ripple. 2. The inductor should be placed as closed as possible to the LX pin to minimize length of the copper tracks as well as the noise coupling into other circuits. 3. Since the feedback pin and network is a high impedance circuit, the feedback network should be routed away from the inductor. The feedback pin and feedback network should be shielded with a ground plane or track to minimize noise coupling into this circuit. 4. A star ground connection or ground plane minimizes ground shifts and noise is recommended. All Right Reserved Akustik Inc. 4/9 Revision

5 Figure 7. PCB Layout guide line 2.8mm 0.45mm 1mm 2.9mm 0.95mm ORDERING INFORMATION 1.6mm 4.0mm Figure 8. SOT-23-6 Footprint Part Number Frequency Package Packaging Remark 1MHz SOT ,000pcs/reel -25~125 Note: Akustik Inc. lead-free products contain molding compounds/die attach materials and 100% matte tin plate termination finish, which are fully compliant with RoHS. Akustik Inc. lead-free products meet the lead-free requirements of IPC/JEDEC J-STD-020C for MSL classification at lead-free peak reflow temperature. Akustik Inc. defines Green to mean lead-free (RoHS compliant) and halogen free (Br or Cl does not exceed 900ppm by weight in homogeneous material and total of Br and Cl does not exceed 1500ppm by weight). PIN DESCRIPTION Pins No. Pins Name I/O Description 1 LX O Step-up Regulator N-MOS Drain. Connect to inductor and output diode. 2 GND I Ground. 3 SENSE I 4 EN/PWM I Sense pin. Connect a resistor R SENSE between SENSE and GND to program the output current: I OUT =0.1V/R SENSE. Enable and current control. When used as enable input, pull high to turn on IC. When used as current control input, the recommend control frequency range is 100Hz~100kHz. 5 OVP I Over voltage protection. The typical value is 30V. 6 IN I Input pin. Decouple this pin to GND pin with a capacitor. All Right Reserved Akustik Inc. 5/9 Revision

6 ABSOLUTE MAXIMUM RATING Parameter Symbol Min. Max Unit Input Voltage V IN V Output Voltage Range V OVP V LX Pin Voltage Range V LX V EN/PWM Pin Voltage Range V EN V All other Pins V GND, V SENSE V Junction Temperature T J Operation Ambient Temperature T OPR Storage Temperature T STG Package Thermal Resistance SOT-23-6 θ JA /W Power A =85 SOT-23-6 P D W Lead temperature (Soldering, 10 sec) ESD Voltage Protection *1 HBM V HBM V MM V MM V Stress beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliablity. *1 Class 3: Human Body Mode (HBM)>4KV, Machine Mode (MM): 200V~399V DC CHARACTERISTICS Test Condition: V cc = 3V, TA = 25 C, unless otherwise specified. IN PIN (Input Voltage, Pin 6) Parameter Symbol Conditions Min. Typ. Max. Unit Input Voltage Range V IN V Quiescent Current I Q V SENSE =0.3V ma Shutdown Current I SHDN EN= μa Input UVLO Threshold V UVLO V UVLO Hysteresis V HYS V LX PIN (Step-up Regulator N-MOS Drain, Pin1) Parameter Symbol Conditions Min. Typ. Max. Unit Low Side Main FET RON R DS(ON) mω Main FET Current Limit I LIM A Max Duty Cycle D MAX % SENSE PIN (Feedback Function, Pin 3) Sense Reference Voltage Parameter Symbol Condition Min. Typ. Max. Unit V REF All Right Reserved Akustik Inc. 6/9 Revision % mv SENSE Input Current I SENSE V SENSE =0.3V na OVP PIN (Protection Function, Pin 5) Parameter Symbol Condition Min. Typ. Max. Unit Output Clamp voltage V Open No Loading V EN/PWM (Enable and PWM Current Control, Pin 4) Parameter Symbol Condition Min. Typ. Max. Unit EN Rising Threshold V ENH V EN Falling Threshold V ENL V PWM control frequency F D K Hz Others Parameter Symbol Condition Min. Typ. Max. Unit

7 Switch Frequency (MHz) Quiescent Current (ua) Realistic Innovation Oscillator Frequency f OSC MHz Thermal Shutdown T SD Thermal Hysteresis T HYST TYPICAL PERFORMANCE CHARACTERISTICS Quiescent Current vs Input Voltage Sense=0.3, EN=2V Input Voltage (V) 1.2 Frequency vs Input Voltage Input Voltage (V) All Right Reserved Akustik Inc. 7/9 Revision

8 PACKING INFORMATION Package Type Tape Size ( W1) Pocket Pitch (P) Reel Size (A) Reel Width (W2) Units Per Reel SOT-23-6 (mm) (mm) (mm) Min./Max. (mm) pieces 6 Leads /9.9 3,000 APPENDIX: SOT-23-6 Reflow Condition (IR/Convection or VPR Reflow) Figure 9. Wave Soldering Process Figure 10. Wave Soldering Profile Test Item Method Description SOLDERABILITY MIL-STD-883D , 5sec HOLT MIL-STD-883D Hrs Bias@125 PCT JESD-22-B,A Hrs, 100% RH, 121 TST MIL-STD-883D ~150, 200 Cycles ESD MIL-STD-883D VHMB>2KV, VMM>200V Latch-Up JESD 78 10mS, 1 tr > 100mA Akustik Inc. cannot assume responsibility for use of any circuit other than circuit entirely embodied in All Right Reserved Akustik Inc. 8/9 Revision

9 any Akustik Inc. products. Akustik Inc. reserves the right to change the circuitry and specifications without notice anytime. Akustik Inc. China 6F, Wing Wah Industrial Building, Yeung Uk Road, Tsuen Wan, N.T. Hong Kong Tel: Taiwan Office 20F., No.229, Sec. 3, Zhongxing Rd., Xindian Dist., New Taipei City 231, Taiwan 260, Taiwan REVISION HISTORY SALES INQUIRY: More information on Changes Revision Number Released Date Description on Pages 1.0 Jan 15 th 2013 Initial Specification All 1.01 July 1 st 2013 Revised Specification All All Right Reserved Akustik Inc. 9/9 Revision