High Efficiency 1MHz, 2A, Step up Regulator General Description EC9208 Features EC9208 is a high efficiency, current‐mode control Boost DC to DC regulator with an integrated 120mΩ RDS(ON) N‐channel MOSFET. The fixed 1MHz switching frequency and internal compensation reduce external component count and save the PCB space. The build‐in internal soft start circuitry minimizes the inrush current at start‐up. ●Wide input range:2.7V~6V ● 1MHz switching frequency ●Minimum on time: 100ns typical ●Minimum off time: 100ns typical ●Max output voltage: 6V ●Low RDS(0N): 120mΩ ●RoHS Compliant and Halogen Free ●Compact package: SOT23-6 Applications ●Cell Phone and Smart Phone ●PDA, PMP, MP3 ●Digital Camera Package Types SOT23-6 Figure 1. Package Types of EC9208 E-CMOS Corp. (www.ecmos.com.tw) Page 1 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Pin Configurations Figure 2 Pin Configuration of EC9208(Top View) Pin Description Pin Name Description 1 LX Inductor node. Connect an inductor between IN pin and LX pin. 2 GDN GND 3 FB Pin Number Feedback pin. Connect a resistor R1 between VOUT and FB, and a resistor R2 between FB and GND to program the output voltage: VOUT=0.6V*(R1/R2+1) 4 EN Enable control. High to turn on the part. Don’t leave it floated. 5 IN Power Input pin. 6 NC E-CMOS Corp. (www.ecmos.com.tw) Page 2 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Ordering Information Part Number EC9208NNB3R Package SOT23-6 Marking Marking Information 9208f 1. Starting with underlined 2, a bar is for production year 2012. The next bar is mark on top of 0 is for year 2013. The next bar is mark on bottom of 0 is for year 2014.The next bar is mark on top of 8 is year for 2015. The naming pattern continues with consecutive characters for later years. 2. f is the week of production. The big character of A~Z is for the week of 1~26, and small a~z is for the week of 27~52. Function Block Figure 3 Function Block Diagram of EC9208 E-CMOS Corp. (www.ecmos.com.tw) Page 3 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Absolute Maximum Ratings EN, VDD, LX‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐7V FB‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐3.6V Power Dissipation, PD @ TA = 25°C, SOT23‐6 ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 0.6W Package Thermal Resistance (Note 2) SOT23‐6, θJA ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 200°C/W SOT23‐6, θJC ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 130°C/W Junction Temperature Range ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 125°C Lead Temperature (Soldering, 10 sec.) ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 260°C Storage Temperature Range ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐65°C to 150°C Recommended Operating Conditions VDD pin‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 2.7V to 6V FB‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 0V to 1V Junction Temperature Range ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐40°C to 125°C Ambient Temperature Range ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ‐40°C to 85°C Electrical Characteristics (VIN = 3.3V, VOUT=5V, IOUT=100mA, TA = 25°C unless otherwise specified) Parameters Symbol Test Condition Min. Typ. VIN Quiescent Current IQ Low Side Main FET Rds(on) Main FET Current ILIM1 3 Switching Frequency Fsw 0.8 1 1.2 MHz Feedback Reference VREF 0.588 0.6 0.612 V IN UVLO Rising VIN,UVLO 2.5 V Thermal Shutdown TSD VFB=0.66V 6 Unit Input Voltage Range E-CMOS Corp. (www.ecmos.com.tw) 2.7 Max. 200 µA 120 mΩ A 150 Page 4 of 11 V °C 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Typical Performance Characteristics E-CMOS Corp. (www.ecmos.com.tw) Page 5 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Typical Performance Characteristics(Cont.) E-CMOS Corp. (www.ecmos.com.tw) Page 6 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Typical Performance Characteristics(Cont.) E-CMOS Corp. (www.ecmos.com.tw) Page 7 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Typical Application Circuit Figure 4. Typical a p p l i c a t i o n C i r c u i t 1 Figure 5. Typical Application Circuit 2 E-CMOS Corp. (www.ecmos.com.tw) Page 8 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Function Description Because of the high integration in the EC9208 IC, the application Boost inductor L: circuit based on this regulator IC is rather simple. Only input capa There are several considerations in choosing this inductor. citor CIN, output capacitor COUT, inductor L and feedback resistors 1) Choose the inductance to provide the desired ripple current. (R1 and R2) need to be selected for the targeted applications spe It is suggested to choose the ripple current to be about 40% cifications. of the maximum average input current. Feedback resistor dividers R1 and R2: The inductance is calculated as: Choose R1 and R2 to program the proper output voltage. To minimize the power consumption under light loads, it is desirable to choose large resistance values for both R1 and R2. A value of between 10k and 1M is recommended for both resistors. where FSW is the switching frequency and IOUT,MAX is If R1=200k is chosen, then R2 can be calculated to be: the maximum load current. The EC9208 regulator IC is quite tolerant of different ripple current amplitude. Consequently, the final choice of inductance can be slightly off the calculation value without significantly impacting the performance. 2) The saturation current rating of the inductor must be selected to be greater than the peak inductor current under full load conditi ons. Output capacitor COUT: The output capacitor is selected to handle the output ripple noise requirements. Both steady state ripple and transient requirements must be taken into consideration when selecting this capacitor. 3) The DCR of the inductor and the core loss at the switching For the best performance, it is recommended to use X5R or bette frequency must be low enough to achieve the desired r grade ceramic capacitor with 25V rating and more than two pcs efficiency requirement. It is desirable to choose an inductor 10uF capacitor. with DCR<50mohm to achieve a good overall efficiency. Input capacitor CIN: Enable Operation The ripple current through input capacitor is calculated as: Pulling the EN pin low (<0.4V) will shut down the device. During the shut down mode, the EC9208 shut down current drops to lower than 1uA, Driving the EN pin high (>2.0V) will turn on the IC To minimize the potential noise problem, place a typical X5R or better grade ceramic capacitor really close to the VDD and GND pins. Care again. Diode Selection Schottky diode is a good choice for high efficiency operation should be taken to minimize the loop area formed by CIN, and because of its low forward voltage drop and fast reverse recovery. VDD/GND pins. In this case a 22uF low ESR ceramic capacitor The current rating of the diode must meet following: is recommended. E-CMOS Corp. (www.ecmos.com.tw) Page 9 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Application Information The schottky diode reverse breakdown voltage should be larger than the output voltage. Layout Design: The layout design of EC9208 regulator is relatively simple. For the best efficiency and minimum noise problems, we should place the following components close to the IC: CIN, L, R1 and R2 1) It is desirable to maximize the PCB copper area connecting to GND pin to achieve the best thermal and noise performance. If the board space allowed, a ground plane is highly desirable. 2) CIN must be close to Pins IN and GND. The loop area formed by CIN and GND must be minimized. 3) The PCB copper area associated with LX pin must be minimized to avoid the potential noise problem. 4) The components R1 and R2, and the trace connecting to the FB pin must NOT be adjacent to the LX net on the PCB layout to avoid the noise problem. 5) If the system chip interfacing with the EN pin has a high impedance state at shutdown mode and the IN pin is connected directly to a power source such as a Li‐Ion battery, it is desirable to add a pull down 1Mohm resistor between the EN and GND pins to prevent the noise from falsely turning on the regulator at shutdown mode. E-CMOS Corp. (www.ecmos.com.tw) Page 10 of 11 4D10N-Rev.F001 High Efficiency 1MHz, 2A, Step up Regulator EC9208 Package Information SOT23-6 Package Outline Dimensions E-CMOS Corp. (www.ecmos.com.tw) Page 11 of 11 4D10N-Rev.F001