Advanced Power Electronics Corp. APE1911 STEP-UP PWM DC/DC Converter FEATURES DESCRIPTION Input Voltage：3V to 20V The APE1911 is high efficient step-up DC/DC converter. Large output current is possible having a built in internal N channel MOSFET, and using an external coil and diode. The APE1911 can be operated at switching frequencies of 500 kHz allowing for easy filtering and low noise, the size of the external components can be reduced. Output voltage is programmable with 1.0V of standard voltage supply internal, and using externally connected components, output voltage (FB) can be set up at will. The soft-start time can be programmed by outside capacitor; the function prevents overshoot at startup. Build inside Current limit, Thermal Shutdown and enable functions. Output Voltage：3.3V to 32V Duty Ratio：0% to 85% PWM Control Oscillation Frequency：500KHz. Enable and Thermal Shutdown Function. Internal Current Limit. Built-in N-channel MOSFET ESOP-8 & Pb-Free Package. TYPICAL APPLICATION VCC=5V L1 22uH Vout=12V D1 B340A U1 1 R1 100K 2 3 4 C1 C7 470uF 0.1uF C3 Option C2 EN SGND Vcc PGND FB SS APE1911 SW SW 8 7 6 C4 C5 5 470uF 4.7uF R4 11K C8 0.47uF 0.47uF R3 1K VOUT = VFB x (1+R4/R3) , VFB = 1.0V, R3 = 1K ~3KΩ PACKAGE & ORDERING INFORMATION APE1911X Package Type MP : ESOP-8 ( Top View ) EN 1 VCC 2 FB 3 SS 4 Exposed pad 8 SGND 7 PGND 6 SW 5 SW ESOP-8 (EP is connect to SW) Data and specifications subject to change without notice 1 201010182 Advanced Power Electronics Corp. APE1911 ABSOLUTE MAXIMUM RATINGS VCC Pin Voltage (VCC) ------------------------------------ GND - 0.3V to GND + 22V Feedback Pin Voltage (VFB) ------------------------------ GND - 0.3V to 6V ON/OFF Pin Voltage (VEN) ------------------------------- GND - 0.3V to VCC Switch Pin Voltage (VSW ) --------------------------------- GND - 0.3V to 34V SS Pin Voltage (VSS) --------------------------------------- GND - 0.3V to 6V Power Dissipation (PD) ------------------------------------ Internally limited Storage Temperature Range (TST) --------------------- -40°C to +150°C Operating Junction Temperature (TOPJ) --------------- -20°C to +125°C Thermal Resistance from Junction to Case(RthJC) 15°C/W Thermal Resistance from Junction to Ambient(RthJA) 40°C/W 2 Note. RthJA is measured with the PCB copper area (connect to exposed pad) of approximately 1 in (Multi-layer). ELECTRICAL SPECIFICATIONS (VIN=5V, VOUT=12V, TA=25°C, unless otherwise specified) Parameter SYM Operating Supply Voltage VCC TEST CONDITION MIN TYP MAX UNITS 3 - 20 V Output Voltage Range VOUT 3.3 - 32 V Feedback Voltage VFB IOUT=0.1A 0.98 1 1.02 V Feedback Bias Current IFB IOUT=0.1A - 0.1 0.5 uA Quiescent Current ICCQ VFB=1.5V force driver off - 4 6 mA Shutdown Supply Current ISD VEN =0V - 1 10 uA SW pin 400 500 600 KHz Line Regulation VCC =3~0.8*Vout - 1 - % Load Regulation IOUT=50m~1A - 1 - % VSH High (regulator ON) 2 - - VSL Low (regulator OFF) - - 0.8 ISH VEN=2.5V (ON) - 20 - ISL VEN=0.3V (OFF) Oscillation Frequency EN Pin Logic input threshold voltage EN Pin Input Current FOSC V uA - -1 - uA ISS - 8 - uA Switching Current Limit ILIM-sw 2.8 3 - A Internal MOSFET RDSON RDSON Efficiency EFFI SS pin Current VCC=5V - 40 80 VCC=12V - 30 60 VCC=5V, VOUT=12V, IOUT=0.5A - 92 - Maximum Duty Cycle DCMAX VFB=0V - 85 - Minimum Duty Cycle DCMIN VFB=1.5V - 0 - - 145 - Thermal Shutdown Temp TSD mΩ % % °C 2 Advanced Power Electronics Corp. APE1911 PIN DESCRIPTIONS PIN SYMBOL VCC PIN DESCRIPITON IC Power Supply Pin SW Switch pin. Connect external inductor & diode here FB Feedback Pin Shutdown Pin EN H : Normal operation SS Soft-Start Pin. L : Shutdown PGND Power Ground pin SGND Signal Ground pin. BLOCK DIAGRAM Vcc Phase Compensation FB + Regulator + - - Vref=1.0V PWM Controller EN VEN 8uA SS SW Buffer Driver Oscillator Thermal Shutdown 0.06V SGND PGND 3 Advanced Power Electronics Corp. APE1911 FUNCTION DESCRIPTION PWM Control The APE1911 consists of DC/DC converters that employ a pulse-width modulation (PWM) system. In converters of the APE1911, the pulse width varies in a range from 0 to 85%, according to the load current. The ripple voltage produced by the switching can easily be removed through a filter because the switching frequency remains constant. Therefore, these converters provide a low-ripple power over broad ranges of input voltage and load current. Setting the Output Voltage Application circuit item shows the basic application circuit with APE1911 adjustable output version. The external resistor sets the output voltage according to the following equation: VOUT = 1.0V x (1+R4/R3) Table 1 Resistor select for output voltage setting VOUT R3 R4 12V 1K 11K 15V 1.3K 18K 18V 1.3K 22K 24V 1.3K 30K 32V 2.2K 68K Inductor Selection For most designs, Low inductance values are physically smaller but require faster switching, which results in some efficiency loss. The inductor value can be derived from the following equation: L = [VIN x (VOUT-VIN)] / VOUT x ∆ IL x fLx Where is inductor Ripple Current. Large value inductors lower ripple current and small value inductors result in high ripple currents. Choose inductor ripple current approximately 15% of the maximum input current 2.4A, ∆IL=0.18A. VOUT 9V 12V 15V 18V L1 Value 18uH 22uH 25uH 33uH The DC current rating of the inductor should be at least equal to the maximum load current plus half the ripple current to prevent core saturation (2.4A+0.18A). Input Capacitor Selection The input capacitor reduces the surge current drawn from the input and switching noise from the device. The input capacitor impedance at the switching frequency shall be less than input source impedance to prevent high frequency switching current passing to the input. A low ESR input capacitor sized for maximum RMS current must be used. The capacitor voltage rating should be at least 1.5 times greater than the input voltage, and often much higher voltage ratings are needed to satisfy. 4 Advanced Power Electronics Corp. APE1911 FUNCTION DESCRIPTION Output Capacitor Selection The output capacitor is required to keep the output voltage ripple small and to ensure regulation loop stability. The output capacitor must have low impedance at the switching frequency. A low ESR capacitor sized for maximum RMS current must be used. The low ESR requirements needed for low output ripple voltage. The capacitor voltage rating should be at least 1.5 times greater than the input voltage, and often much higher voltage ratings are needed to satisfy. Output Capacitor Selection When laying out the PC board, the following suggestions should be taken to ensure proper operation of the APE1911. These items are also illustrated graphically in below. 1. The power traces, including the Source trace, the Schottky and the C1 trace should be kept short, direct and wide to allow large current flow. 2. The power ground is keep C4’s ground closed and far away signal ground. 3. The signal ground trance is distant from power ground trance. 4. The exposed pad is connecting to SW trace closely and widely. (Reduce IC temperature) 5. Do not trace signal line under inductor. (APE1911 PCB Layout -Top View) 5 Advanced Power Electronics Corp. APE1911 TYPICAL PERFORMANCE CHARACTERISTICS IOUT VS VOUT Vout (V) Vout (V) VCC VS VOUT 13 12.8 12.6 12.4 12.2 12 11.8 11.6 11.4 11.2 11 IOUT=0.1A 3 4 5 6 7 8 9 13 12.8 12.6 12.4 12.2 12 11.8 11.6 11.4 11.2 11 VCC=5V 0 10 100 300 400 500 600 Temperature VS Curret Limit 6.0 6 5.5 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 5.0 Current Limit (A) Current Limit (A) VCC VS Current Limit 4.0 3.0 2.0 1.0 VOUT=24V VCC=5V, Vout=12V 0.0 3 6 9 12 15 18 -50 -25 VCC (V) Temperature VS Frequency 0 25 50 Temperature (℃) 75 100 75 100 Temperature VS VFB 750 1.05 700 1.04 1.03 650 600 VFB (V) Frequency (KHz) 200 IOUT (mA) VCC (V) 550 500 450 1.02 1.01 1.00 0.99 0.98 400 350 0.97 0.96 VCC=5V, Vout=12V IOUT=100mA 300 0.95 250 -50 -25 0 25 50 Temperature (℃) 75 100 -50 -25 0 25 50 Temperature (℃) 6 Advanced Power Electronics Corp. APE1911 TYPICAL PERFORMANCE CHARACTERISTICS Power-ON Wave (VCC=5V, Vout=12V, Load=0.8A, SS=0.47uF) VCC SS Enable-ON Wave (VCC=5V, Vout=12V, Load=0.8A, SS=0.47uF) VEN SS VOUT VOUT ISW ISW 7 Advanced Power Electronics Corp. APE1911 MARKING INFORMATION ESOP-8 Part Number Package Code 1911MP YWWSSS Date Code (YWWSSS) Y：Last Digit Of The Year WW：Week SSS：Sequence 8 Advanced Power Electronics Corp. APE1911 PACKAGE OUTLINES H E Expose Pad Y X θ L DETAIL A b D e y A1 C A A2 7 (4X) Dimensions in Millimeters Min. Nom. Max. A 1.75 A1 0 0.15 A2 1.25 C 0.1 0.2 0.25 D 4.7 4.9 5.1 E 3.7 3.9 4.1 H 5.8 6 6.2 L 0.4 1.27 b 0.31 0.41 0.51 e 1.27 BSC y 0.1 X 2.34 Y 2.34 O θ 0 8O Mold flash shall not exceed 0.25mm per side JEDEC outline: MS-012 BA Symbol DETAIL A Dimensions in Inches Min. Nom. Max. 0.069 0 0.06 0.049 0.0075 0.008 0.01 0.185 0.193 0.2 0.146 0.154 0.161 0.228 0.236 0.244 0.015 0.05 0.012 0.016 0.02 0.050 BSC 0.004 0.092 0.092 O 0 8O