BL8526 2A 1.4M 5.5V Synchronous Buck Converter DESCRIPTION FEATURES The BL8526 is a high efficiency synchronous buck regulator. The device operates from an input voltage range of 3.6V to 5.5V and provides an output voltage from 0.8 to 5V while delivering up to 2A of output current. The internal synchronous switches increase efficiency and eliminate the need for an external Schottky diode. The switching frequency is set by an external resistor or can be synchronized to an external clock. While switching frequency is set to 1.4MHz, BL8526 can allow the use of small external components, such as ceramic input and output caps, as well as small inductors, while still providing low output ripples. Range of Input Voltage: 3.6V~5.5V 1μA Shutdown Current 100% Duty Cycle High Efficiency: 92% No Schottky Diode Required. 3.5A Current Limit 0.8V Reference for Low Output Voltage Operating Temp. Range: -20°C~85°C Demo Board Available APPLICATIONS 100% duty cycle provides low dropout operation extending battery life in portable systems. Cellular phones Digital Cameras MP3 and MP4 players Set top boxes Wireless and DSL Modems USB supplied Devices in Notebooks Portable Devices TYPICAL APPLICATION 2.2uH Vout / 3.3V NC Vin PVDD 10uF LX RT VDD 5.6K 31K COMP GND 10uF FB 10K LC2123 BL8526 www.belling.com.cn 180K 3.3nF 1 BL8526 PACKAGE/ORDER INFORMATION 8 SOP8 7 6 5 ORDER PART NUMBER GE| LLSYW 1 2 3 BL8526CD8TR 4 PIN DESCRIPTION Pin No. 1 2 3 4 5 6 7 8 Symbol N.C PVDD LX GND FB COMP VDD RT Description Not Connected Power Supply for internal power switch Switching Node: PWM output connection to inductor. Ground Pin Pin for Feedback Voltage Compensation Pin Power Supply for internal control circuit Oscillator Resistor Input Pin ABSOLUTE MAXIMUM RATING Parameter Value 5.5V –0.3V to Vin+0.3V –0.3V to Vin+0.3V 125C -40C – 85C -40C - 150C 260C, 10S >2000V 150°C/W Max Input Voltage CE Pin Voltage FB Pin Voltage Max Operating Junction Temperature(Tj) Ambient Temperature(Ta) Storage Temperature(Ts) Lead Temperature & Time ESD (HBM) Thermal resistance: ΘJA www.belling.com.cn 2 BL8526 ELECTRICAL CHARACTERISTICS (Test condition is in 25ºC, VIN=5V) Symbol Parameter VDD Vref Input Voltage Range Feedback Voltage Feedback Leakage current Ifb Iq Quiescent Current LnReg LdReg Fsoc RdsonP RdsonN Ilimit Iswlk Ienlk Vh_en Vl_en Conditions Min 3.6 0.784 Active, Vfb=0.65, No Switching Shutdown Vin=4V to 5.5V Iout=0.1to 2A Line Regulation Load Regulation Switching R3=180K Frequency PMOS Rdson NMOS Rdson Peak Current Limit SW Leakage Vout=5.5V, VSW=0 Current or 5.5V, EN=0V EN Leakage Current EN Input High Voltage EN Input Low Voltage Typ Max Unit 0.8 5.5 0.816 V V 0.1 0.4 uA 450 uA 1 0.1 0.02 uA %/V %/A 1.4 MHz 150 130 3.8 mohm mohm A 10 uA 1 uA VIN0.6 V VIN0.8 V DEMO BOARD BOM No. 1 2 3 4 5 6 Reference C1 C2 C3 L1 U1 R1 Type Capacitor Capacitor Capacitor Inductor IC Resistor Specification MLCC 10uF; SMD 0805 MLCC 10uF; SMD 0805 MLCC 3.3nF; SMD 0805 2.2uH; 3A; SMD, Shielding BL8526; SMD SO-8 10K;SMD 0805; 1% 7 R2 Resistor 31K;SMD 0805; 1% 8 9 R3 R4 Resistor Resistor 180K;SMD 0805; 1% 5.6K;SMD 0805; 5% www.belling.com.cn 3 Note If VOUT is 1.0V, R2 is 2.5K BL8526 DEMO BOARD MEASUREMENT www.belling.com.cn 4 BL8526 APPLICATION INFORMATION Layout is critical to achieve clean and stable operation. The switching power stage requires particular attention. Follow these guidelines for good PC board layout: 1) Place decoupling capacitors as close to the IC as possible 2) Connect input and output capacitors to the same power ground node with a star ground configuration then to IC ground. 3) Keep the high-current paths as short and wide as possible. 4) If possible, connect VDD,LX, and GND separately to a large copper area to help cool the IC to further improve efficiency and long-term reliability. 5) Ensure all feedback connections are short and direct. Place the feedback resistors as close to the IC as possible. 6) Route high-speed switching nodes away from sensitive analog areas VIN R3 1 8 2 7 C3 To VIN R4 C1 3 6 4 5 R1 L1 C2 www.belling.com.cn R2 5 BL8526 PACKAGE OUTLINE Package SOP-8 Devices per reel 2500Pcs Unit mm Package specification： Symbol Dimension (mm) MIN NOM MAX A - - 1.77 A1 0.08 0.18 A2 1.2 A3 Symbol Dimension (mm) MIN NOM MAX D 4.7 4.9 5.1 0.28 E 5.8 6 6.2 1.4 1.6 E1 3.7 3.9 4.1 0.55 0.65 0.75 e b 0.39 - 0.48 L b1 0.38 0.41 0.43 L1 c 0.21 - 0.26 www.belling.com.cn 6 1.27BSC 0.5 0.65 0.8 1.05BSC 0 - 8°