High Efficiency 1.5MHz, Step up Regulator EC9210 General Description Features The EC9210 is a fixed switching frequency (1.5MHz typical), ●Wide 2.7V to 6V Input Voltage Range current-mode, step-up regulator with an integrated N-channel output capacitors for portable devices. The current-mode control ●Built‐in 0.2Ω N‐Channel MOSFET ● Built‐in Soft‐Start ● High Efficiency up to 90% scheme provides fast transient response and good output voltage ● <1mA Quiescent Current During Shutdown accuracy. ● Current‐Mode Operation ● Stable with Ceramic Output Capacitors MOSFET. The device allows the usage of small inductors and The EC9210 includes under-voltage lockout, current limit, and over-temperature shutdown preventing damage in the event of an output overload. ● Fast Transient Response ● Current‐Limit Protection ● Over‐Temperature Protection with Hysteresis ● Available in a TSOT23‐5 Package ● Lead Free and Green Devices Available ●(RoHS Compliant) Applications ●Cell Phone and Smart Phone ●PDA, PMP, MP3 ●Digital Camera ●Boost Regulators Package Types TSOT23-5 Figure 1. Package Types of EC9210 E-CMOS Corp. (www.ecmos.com.tw) Page 1 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Pin Configurations Figure 2 Pin Configuration of EC9210(Top View) Pin Description Pin Name Description 1 LX Switch pin. Connect this pin to inductor/diode here. 2 GDN GND 3 FB 4 EN 5 IN Pin Number E-CMOS Corp. (www.ecmos.com.tw) Feedback Input. The device senses feedback voltage via FB and regulate the voltage at 1.23V. Connecting FB wi th a resistor‐divider from the output that sets the output voltage. Enable Control Input. Forcing this pin above 1.0V enables the device. Forcing this pin below 0.4V to shut it down. In shutdown, all functions are disabled to decrease the supply current below 1μA. Do not left this pin floating. Main Supply Pin. Must be closely decoupled to GND with a 2.2μF or greater ceramic capacitor. Page 2 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Ordering Information Part Number Package Marking EC9210NNT2R TSOT23-5 TD8210 LLLLL E-CMOS Corp. (www.ecmos.com.tw) Page 3 of 16 Marking Information 1. LLLLL：Lot No 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Function Block Figure 3 Function Block Diagram of EC9210 E-CMOS Corp. (www.ecmos.com.tw) Page 4 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Absolute Maximum Ratings Note1: Stresses 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 under "recommended operating conditions" is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability Recommended Operating Conditions Thermal Characteristics Symbol Parameter Typical Value Unit θJA Junction-to-Ambient Resistance in Free Air TSOT23-5 220 ℃/W θJC Junction-to-Case Resistance TSOT23-5 120 ℃/W E-CMOS Corp. (www.ecmos.com.tw) Page 5 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Electrical Characteristics (TA=25°C, Unless otherwise specified) Symbol Parameter VIN Input Voltage IDD1 IDD2 ISD Test Conditions TA=‐40~85oC TJ=-40~120 ℃ VFB=1.3V,no switching Input DC Bias Current UVLO Threshold Voltage UVLO Hysteresis Voltage VFB=1.1V, switching EN=GND VIN Rising VIN Falling Min. 2.7 EC9210 Typ. --- Max. 6 --- 300 ‐--- uA ----2.0 50 1.212 1.205 2 5 1 2.4 150 1.248 1.255 50 1.75 --- mA µA V mV V ‐--2.2 100 1.23 ----- VREF Regulated Feedback Voltage IFB FSW RON FB Input Current Switching Frequency Power Switch On Resistance -50 1.25 --- ILIM Power Switch Current Limit LX Leakage Current 2.2 -1 1.5 0.2 ----- 92 --- 95 2 98 3 0.4 --- 0.7 1 --- DMAX TSS LX Maximum Duty Cycle Soft‐Start Duration VTEN EN Voltage Threshold ILEN TOTP EN Voltage Hysteresis EN Leakage Current Over‐Temperature Protection Over‐Temperature Protection E-CMOS Corp. (www.ecmos.com.tw) VIN=2.7V~6V, TA = 25 ℃ VIN=2.7V~6V, TA = -40 ~ 85 ℃ VEN = 0V, VLX = 0V or 6V, VIN = 6V VEN Rising VEN=5V, VIN = 5V TJ Rising -1 --- TJ Falling --- Page 6 of 16 0.1 --- --1 Unit V nA MHz Ω A uA % ms V V uA 150 1 --- 40 --- ℃ ℃ 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Typical Performance Characteristics E-CMOS Corp. (www.ecmos.com.tw) Page 7 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Typical Performance Characteristics(Cont.) E-CMOS Corp. (www.ecmos.com.tw) Page 8 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Operating Waveforms E-CMOS Corp. (www.ecmos.com.tw) Page 9 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Operating Waveforms(Cont.) E-CMOS Corp. (www.ecmos.com.tw) Page 10 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Typical Application Circuit Figure 4. Typical 5V to 12V Supply Figure 5. Standard 3.3V to 5V Supply E-CMOS Corp. (www.ecmos.com.tw) Page 11 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Typical Application Circuit(Cont.) Figure 6. Multiple Output for TFT-LCD Power Supply E-CMOS Corp. (www.ecmos.com.tw) Page 12 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Function Description Main Control Loop Over-Temperature Protection (OTP) The EC9210 is a constant frequency and current-mode switching The over-temperature circuit limits the junction temperature of the regulator. In normal operation, the internal N channel power EC9210. When the junction temperature exceeds 150℃, a thermal MOSFET is turned on each cycle when the oscillator sets an sensor turns off the power MOSFET allowing the devices to cool. internal RS latch, and then turned off when an internal comparator The thermal sensor allows the converters to start a soft-start (ICMP) resets the latch. The peak inductor current at which ICMP process and regulates the output voltage again after the junction resets the RS latch is controlled by the voltage on the COMP node temperature cools by 40℃. The OTP is designed with a 40℃ which is the output of the error amplifier (EAMP). An external hysteresis to lower the average Junction Temperature (TJ) during resistive divider connected between VOUT and ground allows the continuous thermal overload conditions increasing the lifetime of EAMP to receive an output feedback voltage VFB at FB pin. When the device. the load current increases, it causes a slightly to decrease in VFB Enable/Shutdown associated with the 1.23V reference, which in turn, it causes the Driving EN to the ground places the EC9210 in shutdown mode. COMP voltage to increase until the average inductor current When in shutdown, the internal power MOSFET turns off, all matches the new load current. internal circuitry shuts down, and the quiescent supply current VIN Under-Voltage Lockout (UVLO) reduces to 1μA maximum. The Under-Voltage Lockout (UVLO) circuit compares the input voltage at VIN with the UVLO threshold to ensure the input voltage is high enough for reliable operation. The 100mV (typ) hysteresis prevents supply transients from causing a restart. Once the input voltage exceeds the UVLO rising threshold, startup begins. When the input voltage falls below the UVLO falling threshold, the controller turns off the converter. Soft-Start The EC9210 has a built-in soft-start to control the output voltage rise during start-up. During soft-start, an internal ramp voltage, connected to the one of the positive inputs of the error amplifier, raises up to replace the reference voltage (1.23V typical) until the ramp voltage reaches the reference voltage. Current-Limit Protection The EC9210 monitors the inductor current, flows through the N-channel MOSFET, and limits the current peak at current-limit level to prevent loads and the EC9210 from damaging during overload or short-circuit conditions. E-CMOS Corp. (www.ecmos.com.tw) Page 13 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Application Information Input Capacitor Selection The input capacitor (CIN) reduces the ripple of the input current drawn from the input supply and reduces noise injection into the IC. The reflected ripple voltage will be smaller when an input The peak inductor current is calculated as the following equation: capacitor with larger capacitance is used. For reliable operation, it is recommended to select the capacitor with maximum voltage rating at least 1.2 times of the maximum input voltage. The capacitors should be placed close to the VIN and the GND. Inductor Selection Selecting an inductor with low dc resistance reduces conduction losses and achieves high efficiency. The efficiency is moderated whilst using small chip inductor which operates with higher inductor core losses. Therefore, it is necessary to take further consideration while choosing an adequate inductor. Mainly, the inductor value determines the inductor ripple current: larger inductor value results in smaller inductor ripple current and lower conduction losses of the converter. However, larger inductor value generates slower load transient response. A reasonable design rule is to set the ripple current, ΔIL, to be 30% to 50% of the maximum average inductor current,IL(AVG). The inductor value can be obtained as below, where VIN = input voltage VOUT = output voltage FSW = switching frequency in MHz Output Capacitor Selection IOUT = maximum output current in amp. The current-mode control scheme of the EC9210 allows the usage of tiny ceramic capacitors. The higher capacitor value provides η = Efficiency good load transients response. Ceramic capacitors with low ESR ΔIL /IL(AVG) = inductor ripple current/average current values have the lowest output voltage ripple and are (0.3 to 0.5 typical) recommended. If required, tantalum capacitors may be used as To avoid the saturation of the inductor, the inductor should be well. The output ripple is the sum of the voltages across the ESR rated at least for the maximum input current of the converter plus and the ideal output capacitor. the inductor ripple current. The maximum input current is calculated as below: E-CMOS Corp. (www.ecmos.com.tw) Page 14 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Application Information(Cont.) I Output Capacitor Selection (Cont.) 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 trace to minimize noise coupling into this circuit. 4. A star ground connection or ground plane minimizes ground where IPEAK is the peak inductor current. shifts and noise is recommended. For ceramic capacitor application, the output voltage ripple is dominated by the ΔVCOUT. When choosing the input and output ceramic capacitors, the X5R or X7R with their good temperature and voltage characteristics are recommended. Output Voltage Setting The output voltage is set by a resistive divider. The external resistive divider is connected to the output which allows remote voltage sensing as shown in “Typical Application Circuits”. A suggestion of the maximum value of R1 is 2MΩ and R2 is 200kΩ for keeping the minimum current that provides enough noise rejection ability through the resistor divider. The output voltage can be calculated as below: Diode Selection To achieve the high efficiency, a Schottky diode must be used. The current rating of the diode must meet the peak current rating of the converter. Layout Consideration For all switching power supplies, the layout is an important step in the design especially at high peak currents and switching frequencies. If the layout is not carefully done, the regulator might show noise problems and duty cycle jitter. 1. The input capacitor should be placed close to the VIN and the GND without any via holes for good input voltage filtering. 2. To minimize copper trace connections that can inject noise into the system, the inductor should be placed as close as possible to the LX pin to minimize the noise coupling into other circuits. E-CMOS Corp. (www.ecmos.com.tw) Page 15 of 16 5E29N-Rev.F002 High Efficiency 1.5MHz, Step up Regulator EC9210 Package Information TSOT23-5 Package Outline Dimensions E-CMOS Corp. (www.ecmos.com.tw) Page 16 of 16 5E29N-Rev.F002