SQ25202ABC

Application Note: SQ25202 High Efficiency 1MHz, 2A Step Up Regulator General Description Features The SQ25202 is a high efficiency, current-mode control Boost DC to DC regulator with an integrated 200mΩ 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. • • • • • • • • RO N IR IT Ordering Information Wide Input Range: 3-30V Bias Input, 33VOUT, MAX 1MHz Switching Frequency Minimum ON Time: 100ns typical Minimum OFF Time: 100ns typical Low RDS(ON): 200mΩ RoHS Compliant and Halogen Free Accurate Reference: 0.6VREF Compact Package: SOT23-6 Note ---- Typical Applications L1 4.7uH ON/ OFF 4 1 IN COUT 10uFх2 LX NC SQ25202 EN FB 3 R1 200k GND VIN=5V,VOUT=12V 94 Efficiency (%) 6 de nti a 5 on fi CIN 10uF Efficiency vs. Input Voltage VOUT 12V lP VIN 5V • Digital Camera • Cell Phone • PDA, PMP, MP3 dF Package type SOT23-6 rep are Ordering Number SQ25202ABC or K Applications 92 90 88 86 .C 2 R2 10.5k orp R3 1M 0 0.1 0.2 0.3 0.4 0.5 Load Current (A) Figure 2. Efficiency vs. Load Current Sil erg yC Figure1. Schematic Diagram 84 AN_SQ25202 Rev.0.9 © 2022 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 1 All Rights Reserved. SQ25202 LX 1 6 NC GND 2 5 IN FB 4 EN 3 RO N Pinout (top view) IR IT （SOT23-6） FB 3 EN IN NC 4 5 6 Pin Description Inductor node. Connect an inductor between the IN pin and the LX pin. Ground pin. 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). Enable control. High to turn on the part. Don’t leave it floating. Input pin. Decouple this pin to the GND pin with a 1μF ceramic capacitor. No connection. dF Pin Number 1 2 rep are Pin Name LX GND or K Top Mark: 9Qxyz (Device code: 9Q, x=year code, y=week code, z= lot number code) Input UVLO on fi Internal Power de nti a IN lP Function Block .C VCC yC orp EN Peak Current Sense erg Slope Compensation LX PWM Control & Protect Logic Sil Error Amp VCC Cmp VREF FB Peak Current Sense GND Rc Cc Internal SST OTP Figue3. Block Diagram AN_SQ25202 Rev.0.9 © 2022 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 2 All Rights Reserved. SQ25202 Absolute Maximum Ratings (Note 1) IR IT RO N LX Voltage -------------------------------------------------------------------------------------------------------- -0.3V to 36V IN, EN Voltage --------------------------------------------------------------------------------------------------- -0.3V to 33V FB Voltage ---------------------------------------------------------------------------------------------------------- -0.3V to 4V Power Dissipation, PD @ TA = 25°C SOT23-6 -------------------------------------------------------------------------- 0.6W Package Thermal Resistance (Note 2) θ JA ------------------------------------------------------------------------------------------------------------- 161°C/W θ JC ------------------------------------------------------------------------------------------------------------- 130°C/W Junction Temperature Range ---------------------------------------------------------------------------------- -40°C to 150°C Lead Temperature (Soldering, 10 sec.) --------------------------------------------------------------------------------- 260°C Storage Temperature Range ----------------------------------------------------------------------------------- -65°C to 150°C Recommended Operating Conditions (Note 3) Sil erg yC orp .C on fi de nti a lP rep are dF or K Input Voltage Supply-------------------------------------------------------------------------------------------------- 3V to 30V Junction Temperature Range ---------------------------------------------------------------------------------- -40°C to 125°C Ambient Temperature Range ------------------------------------------------------------------------------------ -40°C to 85°C AN_SQ25202 Rev.0.9 © 2022 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 3 All Rights Reserved. SQ25202 Electrical Characteristics (VIN = 5V, VOUT=12V, IOUT=100mA, TJ= -40°C to +125°C. Typical values are at TJ=25°C, unless otherwise specified. The values are guaranteed by test, design or statistical correlation. ) Min 3 1.3 100 5 200 IR IT VFB=0.66V EN=0 Typ 2 0.8 0.582 1.5 1 0.6 85 90 100 10% 150 10 or K EN=0 Max 30 2.2 150 20 320 3 1 1.32 0.618 RO N Test Conditions dF Symbol VIN VIN,UVLO IQ ISHDN RDS(ON) ILIM1 ILK fsw VREF VENH VENL DMAX tON, MIN tOFF, MIN TSD THYS rep are Parameter Input Voltage Range IN UVLO Rising Threshold Quiescent Current Shutdown Current Low Side Main FET RON Main FET Current Limit Main FET Leakage Current Switching Frequency Feedback Reference Voltage EN Rising Threshold EN Falling Threshold Max Duty Cycle Min ON Time Min OFF Time Thermal Shutdown Temperature Thermal Shutdown Hysteresis 0.4 150 15% Unit V V µA µA mΩ A μA MHz V V V % ns TS °C °C de nti a lP Note 1: Stresses beyond “Absolute Maximum Ratings” may cause permanent damage to the device. These are for stress ratings. 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 reliability. on fi Note 2: θ JA is measured in the natural convection at TA = 25°C on a low effective single layer thermal conductivity test board of JEDEC 51-3 thermal measurement standard. Test condition: Device mounted on 2” x 2” FR-4 substrate PCB, 2oz copper, with minimum recommended pad on top layer and thermal vias to bottom layer ground plane. Sil erg yC orp .C Note 3: The device is not guaranteed to function outside its operating conditions. AN_SQ25202 Rev.0.9 © 2022 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 4 All Rights Reserved. SQ25202 Typical Performance Characteristics Load Transient Efficiency vs. Input Voltage (VIN=5V, VOUT=12V,Iload=0.1~0.5A) VIN=5V,VOUT=12V VOUT(AC) 92 RO N (0.2V/div) 90 88 Io 86 IR IT Efficiency (%) 94 (0.5A/div) 84 0 0.1 0.2 0.3 0.4 0.5 Time(100us/div) or K Load Current (A) Output Ripple Output Ripple dF (VIN=5V, VOUT=12V,Iload=0.5A) (VIN=5V, VOUT=12V,Iload=0.2A) VO(AC) (20mV/div) rep are VO(AC) (20mV/div) VLX (5V/div) lP IL (0.5A/div) de nti a VLX (10V/div) Output Ripple Time(400ns/div) on fi Time(400ns/div) IL (0.5A/div) .C (VIN=5V, VOUT=12V,Iload=0.04A) orp VO(AC) (20mV/div) erg IL (0.5A/div) yC VLX (5V/div) Sil Time(40us/div) AN_SQ25202 Rev.0.9 © 2022 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 5 All Rights Reserved. SQ25202 VEN Startup from Enable Shutdown from Enable f=10Hz, VIN=5V,VOUT=12V,IO=0.5A f=10Hz, VIN=5V,VOUT=12V,IO=0.5A VEN 5V/div VOUT 5V/div VLX 5V/div RO N 0.2A/div VOUT 5V/div IO 0.2A/div VLX 5V/div IR IT IO 5V/div Time (100us/div) or K Time (100us/div) Shudown from VIN Startup from VIN VIN=5V,VOUT=12V,IO=0.5A VOUT 10V/div VLX 10V/div IO 0.5A/div lP 2V/div VIN 2V/div VOUT 10V/div VLX 10V/div IO 0.5A/div Time (2ms/div) Sil erg yC orp .C on fi Time (2ms/div) de nti a VIN rep are dF VIN=5V,VOUT=12V,IO=0.5A AN_SQ25202 Rev.0.9 © 2022 Silergy Corp. Silergy Corp. Confidential- Prepared for Customer Use Only 6 All Rights Reserved. SQ25202 1) Choose the inductance to provide the desired ripple current. It is suggested to choose the ripple current to be about 40% of the maximum average input current. The inductance is calculated as: Applications Information Because of the high integration in the SQ25202 IC, the application circuit based on this IC is rather simple. Only the input capacitor CIN, the output capacitor COUT, the inductor L and the feedback resistors (R1 and R2) need to be selected for the targeted applications specifications. (VOUT − VIN)  VIN  L=   VOUT  fSW  IOUT_MAX  40% RO N 2 Where fSW is the switching frequency and IOUT,MAX is the maximum load current. The SQ25202 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. or K IR IT Feedback Resistor Dividers R1 and R2: 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. If R1=200k is chosen, then R2 can be calculated to be: dF 2) The saturation current rating of the inductor must be selected to be greater than the peak inductor current under full load conditions. R 2 =(R1  0.6V)/(VOUT -0.6V) VIN(VOUT − VIN)  VOUT  ISAT,MIN     IOUT_MAX + 2  fSW  L  VOUT  VIN  rep are VOUT R1 0.6VFB 3) The DCR of the inductor and the core loss at the switching frequency must be low enough to achieve the desired efficiency requirement. It is desirable to choose an inductor with DCR