BL8519 Built-in 2A Power MOSFET Step-down DC-DC Converter DESCRIPTION FEATURES ◆ ◆ ◆ ◆ ◆ ◆ BL8519 is a current mode PWM step-down DC-DC converter that has an internal 2A power switch. It has a wide input voltage range of 3.6V to 20V, which make it suitable for regulating a wide variety of power sources. Range of Input Voltage: 3.6V~20V Built-in 90mΩ Power MOSFET <5µA Shutdown Current Oscillation Frequency: 500KHz High efficiency: 90% 2.5A Peak Current Limit Cycle by Cycle ◆ Operating Temperature Range: -40℃ ~85℃ ◆ Demo Board Available BL8519 is made up of a PWM control circuit, a reference voltage unit, an error amplifier, a protection circuit, Chip Enable circuit, and under voltage lockout circuit. A low ripple high efficiency step-down DC-DC converter can be easily assembled by this IC with minimum external components: an inductor, a diode, capacitors and resistors. Desired output voltage can be achieved by adjusting the value of external resistors. APPLICATIONS ◆ Power source for portable communication equipment, cameras, video instruments such as VCRs, camcorders. ◆ Power source for battery-powered equipment. ◆ Power source for household electrical appliance The BL8519 has cycle-by-cycle current limit circuitry; current limiting provides protection against shorted output. The low current (<5uA) shutdown provides complete output disconnect, enabling easy power management in battery powered systems. TYPICAL APPLICATION BL8 BL8519 www.belling.com.cn 1 BL8519 ORDERING INFORMATION PIN CONFIGURATION BL8519 1 2 3 Code Product Classification 1 2 3 Description Marking Temperature & Rohs: C: -40~85°C, Pb Free Rohs Std. Package Type: D8: SOP-8 Packing Type: TR: Tape & Reel (Standard) HG XX YYBZZ HG: Product Code XX: Output Voltage Adjustable YY: LOT NO. B: FAB Code ZZ: Date Code PIN DESCRIPTIO Pin No. Symbol 1 NC Not Connected 2 VIN Power Supply Pin 3 SW Switching Node: PWM output connection to inductor. 4 GND 5 FB Pin for Feedback Voltage 6 NC Not Connected 7 CE Chip Enable Pin (Active with “H”) 8 NC Not Connected Description Ground Pin BLOCK DIAGRAM www.belling.com.cn BL8519CD8TR 2 8 7 6 5 HGXX YYBZZ 1 2 3 4 BL8519 ABSOLUTE MAXIMUM RATING Supply Voltage SW Pin Voltage CE Pin Voltage FB Pin Voltage Operating Ambient Temperature Range Storage Temperature Range Lead Temperature (Soldering, 10 sec) Thermal resistance: ΘJA 23V 25V –0.3V to Vin+0.3V –0.3V to 6V –40°C to 85°C –65°C to 150°C 260°C 150°C/W ELECTRICAL CHARACTERISTICS (Test condition: Ta=25ºC, VIN=12V,unless otherwise noted.) Symbol Item Conditions Min. VUVLO VFB IFB IQ △VFB/△V △VFB/△T FOSC_MAX FOSCTH DMAX ILIMIT Rds_on ISW ICEH Under Voltage Lockout Feedback Voltage FB Pin Bias Current Supply Current Quiescent Current in Shutdown Reference Line Regulation Feedback Voltage Temperature Coefficient Oscillator Frequency Frequency Shift Threshold on FB Pin Max Duty Cycle Switch Current Limit Static P-Channel MOSFET On State Resistance Switch Leakage Current CE “H” Input Current 1.225 VFB=1.25V VFB=1.3V, VCE=VIN VCE=0V VIN=5V to 20V Max. Unit 3.35 1.25 150 2 3.6 1.275 600 V V nA mA 2 5 uA 0.08 %/V ±100 ppm/℃ VFB=1.1V 500 KHz FSW=200K 0.44 V -40℃ ≤ Topt≤ 85℃ VCE =3V ICEL CE “L” Input Current VCE = 0V VCEH CE “H” Input Voltage VIN = 12V VCEL CE “L” Input Voltage VIN = 12V www.belling.com.cn Typ. 97 % 2.5 A 90* mΩ 1 uA 6.7 15 uA 0.03 0.1 uA 1.8 V 0.4 3 V BL8519 DEMO BOARD BOM No. Reference Type Specification 1 C1 Capacitor MLCC 10uF; SMD 0805 2 C2 Capacitor MLCC 10uF; SMD 0805 3 D1 Diode SS34; 40V, 3A; SMD 4 L1 Inductor 10uH; 3A; SMD, Shielding 5 IC1 IC BL8519; SMD SOP-8 6 R1 Resistor SMD 0805; 30K；1% 7 R2 Resistor SMD 0805; 10K；1% Note LAYOUT CONSIDERATION Careful PCB layout is critical to achieving low switching losses and clean, stable operation. The switching power stage requires particular attention. If possible, mount all the power components on one side of the board, with their ground terminals as close to one another as possible. Keep the high-current paths short, especially the distance between Cin and the Vin (GND) terminals. It is essential for stable, jitter-free operation, showing as the following figure. The ESR of Cin should be smaller enough and the capacitance of Cin should be large enough for filtering the switching noise across power path, a 10uF ceramic capacitor is recommended. Keep the trace connecting to SW terminal wide enough for heat dissipation, if possible, it is better to place some vias connected to the bottom copper for enhancement. Route high-speed switching nodes, for example SW terminal, away from sensitive analog trace (eg. FB terminal). www.belling.com.cn 4 BL8519 DEMO BOARD MEASUREMENT Load Regulation (VOUT=5V) 100 90 80 70 60 50 40 30 20 10 0 6.0 Output Voltage(V) Efficiency(%) Efficiency vs. Load Current (VOUT=5V) 5.5 5.0 4.5 4.0 3.5 0 500 1000 1500 0 500 Load Current(mA) VIN=6V VIN=12V VIN=18V VIN=6V CE Pin Bias Current vs. CE Pin Voltage Feedback Voltage(V) CE Pin Bias Current(uA) 70 60 50 40 30 20 10 0 3 6 9 12 15 VIN=12V VIN=18V 1.30 1.29 1.28 1.27 1.26 1.25 1.24 1.23 1.22 1.21 1.20 5 18 8 11 14 17 Supply Voltage(V) CE Pin Voltage(V) Quiesent Current vs. Supply Voltage (VCE=0V) Supply Current vs. Supply Voltage (VFB=1.3V,VCE=VIN) 2.5 Supply Current(mA) 4 Quiesent Current(uA) 1500 Feedback Voltage vs.Supply Voltage 80 0 1000 Load Current(mA) 3 2 1 0 2.0 1.5 1.0 0.5 0.0 0 3 6 9 12 15 0 18 Supply Voltage(V) www.belling.com.cn 3 6 9 12 Supply Voltage(V) 5 15 18 BL8519 Feedback Voltage vs. Temperature 700 1.6 600 1.4 Feedback Voltage(V) Frequency(KHz) Frequency vs.Temperature 500 400 300 200 100 0 -40 1.2 1.0 0.8 0.6 0.4 0.2 0.0 -15 10 35 60 85 -40 Temperature -15 10 35 60 85 Temperature(?C) Transient Loading Response CH1: Output Current CH1: Output Current CH2: Output Voltage CH2: Output Voltage www.belling.com.cn 6 BL8519 PACKAGE LINE Package SOP-8 Devices per reel 2500Pcs Unit mm Package specification： Symbol A A1 A2 A3 b b1 c MIN 0.08 1.2 0.55 0.39 0.38 0.21 www.belling.com.cn Dimension (mm) NOM 0.18 1.4 0.65 0.41 - Symbol MAX 1.77 0.28 1.6 0.75 0.48 0.43 0.26 D E E1 e L L1 θ 7 MIN 4.7 5.8 3.7 0.5 0 Dimension (mm) NOM 4.9 6 3.9 1.27BSC 0.65 1.05BSC - MAX 5.1 6.2 4.1 0.8 8°