BL8505 High Efficiency PFM Step-up DC/DC Converter Features Outline Applications Selection Guide BL8505 XX X Pin Configurations XX package Function description Output voltage www.belling.com.cn Ver1.1 1/10 BL8505 Pin Description: Pin No. SOT-89-3 TO-92 SOT-23-3 SOT-89-5 SOT-23-5 Symbol Description Product List: Product Name Output Voltage LX Tr. Driver Chip Enable Package Block Diagram Absolute Maximum Ratings: www.belling.com.cn Ver1.1 2/10 BL8505 Recommended Operating Conditions: Min Nom Max Unit *Suggestion Electrical Characteristics: Symbol Item www.belling.com.cn Test Conditions Min Ver1.1 Reference Data Typ. Max Unit 3/10 BL8505 Typical Characteristics Detailed Description: Selection Of The External Components: D 1 Vout Vin Vout Inductor Selection www.belling.com.cn Ver1.1 4/10 BL8505 2 L min D(1 D) RL 2f Lmin D Vin Lf Vin Im ax (1 D) 2 RL I DVin 2 Lf rL Rload (1 D) 2 2 Capacitor Selection r Vout Vout r' r 3 D Rload Cf Im ax RESR Vout Diode Selection www.belling.com.cn Ver1.1 5/10 BL8505 4 Input Capacitor Test Circuits 3 www.belling.com.cn Ver1.1 6/10 BL8505 Typical Characteristics L=10uH Output Voltage(V) 3.5 Vin=0.9V 3.4 Vin=1.0V 3.3 Vin=1.5V Vin=1.8V 3.2 Vin=2.0V 3.1 3 2.9 2.8 2.7 0 50 100 150 200 250 300 350 400 450 500 Output Current(mA) www.belling.com.cn Ver1.1 7/10 BL8505 L=10uH Efficiency (%) 100 90 80 Vin=0.9V Vin=1.0V Vin=1.5V Vin=1.8V Vin=2.0V 70 60 50 0 50 100 150 200 250 300 350 400 450 500 Output Current(mA) L=47uH 3.5 Vin=0.9V Vin=1.0V Vin=1.5V Vin=1.8V Vin=2.0V Output Voltage(V) 3.4 3.3 3.2 3.1 3 2.9 2.8 2.7 0 50 100 150 200 250 300 350 400 450 500 Output Current(mA) L=47uH (%) 90 Efficiency 100 80 Vin=0.9V Vin=1.0V 70 Vin=1.5V Vin=1.8V 60 Vin=2.0V Vin=2.5V 50 0 50 100 150 200 250 300 350 400 450 500 Output Current(mA) www.belling.com.cn Ver1.1 8/10 BL8505 L=100uH Output Voltage(V) 3.3 Vin=0.9V Vin=1.0V Vin=1.5V Vin=1.8V Vin=2.0V 3.2 3.1 3 2.9 2.8 2.7 0 50 100 150 200 250 300 350 400 450 500 Output Current(mA) L=100uH (%) 100 Vin=0.9V Vin=1.0V Vin=1.5V Vin=1.8V Vin=2.0V 90 Efficiency 80 70 60 50 0 50 100 150 200 250 300 350 400 450 500 Output Current(mA) L=47uH Ripple Voltage Vr(mVp-p) 140 120 100 80 Vin=0.9V 60 Vin=1.0V 40 Vin=1.5V 20 Vin=1.8V Vin=2.0V 0 0 50 100 150 200 250 300 350 400 450 500 Output Current(mA) www.belling.com.cn Ver1.1 9/10 BL8505 Package Outline www.belling.com.cn Ver1.1 10/10