Advanced Power Electronics Corp. APE1912 STEP-UP PWM DC/DC CONVERTER FEATURES DESCRIPTION Input Voltage：3V to 13V The APE1912 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 APE1912 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 20V 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. Halogen Free Product TYPICAL APPLICATION L1 2.2uH VCC= 3.0 ~ 4.5V Vout= 5 V D1 B540A U1 R1 100K EN NC FB SW SS APE1912 C1 10uF C3 0.1uF C2 SGND Vcc PGND C4 C5 220uF 22uF R4 12K C8 0.47 uF 0.47uF R3 3K R5 470R C7 0.1uF VOUT < 8V, VOUT = VFB x (1+R4/R3) , VFB = 1.0V, R3 = 1K 20mΩ < Cout ESR < 80mΩ Data and specifications subject to change without notice 1 20130222V1.1 Advanced Power Electronics Corp. APE1912 ABSOLUTE MAXIMUM RATINGS VCC Pin Voltage (VCC) ----------------------------------- GND - 0.3V to GND + 14V 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 22V SS Pin Voltage (VSS) -------------------------------------- GND - 0.3V to 6V Power Dissipation (PD) ----------------------------------- Internally limited Storage Temperature Range (T ST) -------------------- -40°C to +150°C Operating Junction Temperature (T OPJ) -------------- -20°C to +125°C Thermal Resistance from Junction to Case(Rth JC) 15°C/W Thermal Resistance from Junction to Ambient(RthJA) 40°C/W Note. RthJA is measured with the PCB copper area (connect to exposed pad) of approximately 1 in2(Multi-layer). ELECTRICAL SPECIFICATIONS (VIN=3.3V, VOUT=5V, TA=25oC, unless otherwise specified) Parameter SYM Operating Supply Voltage VCC TEST CONDITION MIN TYP MAX UNITS 3 - 13 V Output Voltage Range VOUT 3.3 - 20 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 ICCQ VFB=1.5V force driver off - 4 6 mA ISD VEN =0V - 1 10 uA FOSC SW pin 400 500 600 KHz Quiescent Current Shutdown Supply Current Oscillation Frequency Line Regulation VCC =3~0.8 x 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 - uA ISL VEN=0.3V (OFF) - -1 - uA EN Pin Logic input threshold voltage EN Pin Input Current SS pin Current V ISS - 8 - uA Switching Current Limit ILIM-sw 5 6 - A Internal MOSFET RDSON RDSON VCC=5V - 25 - VCC=3.3V - 35 - Efficiency EFFI VCC=3V, VOUT=5V, IOUT=0.5A - 90 - Maximum Duty Cycle DCMAX VFB=0V - 85 - Minimum Duty Cycle DCMIN VFB=1.5V - 0 - - 145 - Thermal Shutdown Temp TSD mΩ % % o C 2 Advanced Power Electronics Corp. APE1912 PACKAGE & ORDERING INFORMATION ( Top View ) APE1912X Package Type MP : ESOP-8 EN 1 VCC 2 FB 3 SS 4 Exposed pad 8 SGND 7 NC 6 SW 5 PGND ESOP-8 ( EP is connect to SW) 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 L : Shutdown SS Soft-Start Pin. 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. APE1912 FUNCTION DESCRIPTION PWM Control The APE1912 consists of DC/DC converters that employ a pulse-width modulation (PWM) system. In converters of the APE1912, 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 APE1912 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 V OUT R3 R4 5V 3K 12K 12V 1K 11K 15V 1.3K 18K 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. 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. 4 Advanced Power Electronics Corp. APE1912 FUNCTION DESCRIPTION Output Capacitor Selection When laying out the PC board, the following suggestions should be taken to ensure proper operation of the APE1912. 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 & RFB 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. 5 Advanced Power Electronics Corp. APE1912 TYPICAL PERFORMANCE CHARACTERISTICS Temperature VS VFB 1.05 700 1.04 1.03 650 600 VFB (V) Frequency (KHz) Temperature VS Frequency 750 550 500 450 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 (℃) 75 100 6 Advanced Power Electronics Corp. APE1912 MARKING INFORMATION ESOP-8 Part Number Package Code 1912MP YWWSSS Date Code (YWWSSS) Y：Last Digit Of The Year WW：Week SSS：Sequence 7