BL9342

BL9342 40V, 600mA , Step-Down Converter Description The BL9342 is a high frequency (1.8MHz) step-down switching regulator with integrated internal high-side high voltage power MOSFET. It provides single 0.6A(or less) highly efficient output with current mode control for fast loop response. The wide input range(4.2V to 40V) accommodates a variety of step-down applications. Low shutdown mode quiescent current allows use in battery-powered applications. High efficiency at light load condition is achieved by scaling down the switching frequency to reduce the switching and gate driving losses. The BL9342 is available in SOT23-6L package. Features             4.2 V to 40 V operating input range 230uA operating quiescent current. Low shutdown supply current 500mΩ internal power MOSFET 1.8 MHz fixed switching frequency >90% efficiency Internally compensated Stable with ceramic output capacitors Internal soft-start Thermal shutdown function Precision current limit without current sensing resistor SOT23-6L package Applications     High voltage power conversion Industrial power systems Power meter Battery powered systems www.belling.com.cn 1 V1.0 BL9342 Function Block Diagram Package Reference www.belling.com.cn 2 V1.0 BL9342 Typical Application Circuits Absolute Maximum Ratings Description Value Supply Voltage(VIN) –0.3V to 43V Switch Voltage (VSW) –0.3V to VIN (MAX)+0.3V BST to SW -0.3 to 6.0V All Other Pins –0.3V to 5.0V Continuous Power Dissipation(TA=+25℃) Junction Temperature 0.57W Lead Temperature 260℃ Storage Temperature -65°C to 150℃ 150℃ Recommended Operating Conditions Description Value Supply Voltage Vin 4.2V to 40V Output Voltage VOUT Up to 40V Operating Junction Temp(TJ) –40℃ to +125℃ Thermal Resistance SOT23-6L www.belling.com.cn θJA θJC 220 110 ℃/W 3 V1.0 BL9342 Electrical Characteristics Vin=12V, Ven=2V, Ta=25℃, unless otherwise noted。 Symbol Parameter Condition Vfb Feedback Voltage Rsw Upper Switch Resistance Iswleak Upper Switch Leakage Ilim Current Limit Gcs Transconductance Vin min Minimum Voltage Vin(UVLO) UVLO Up Threshold Vin(UVLO)hys UVLO Hysteresis Tss Soft-Start Time Fosc ON Min Typ Max Units 0.794 V Vbst-Vsw=5V 500 mΩ Ven=0V, Vsw=0V 0.1 COMP to SENSE Operating 1 uA 1 A 3 A/V 4.2 V 3.3 4.2 V 0.8 V 0.5 msec Oscillator Frequency 1.8 MHz Ton min Minimum Switch ON Time 100 ns Isd Shutdown Current Ven