Single-chip Type with Built-in FET Switching Regulator Series High-efficiency Step-up/down Switching Regulators with Built-in Power MOSFET No.09027EBT08 BD8305MUV General Description ROHMs highly-efficient step-up/down switching regulator BD8305MUV produces step-up/down output including 3.3 V from 1 cell of lithium battery with just one coil. This IC adopts an original step-up/down drive system and creates a higher efficient power supply than conventional Sepic-system or H-bridge system switching regulators. Features 1) Highly-efficient step-up/down DC/DC converter to be constructed just with one inductor. 2) Input voltage 2.5 V - 5.5 V 3) Output current 1 A at 3.3 V 800 mA at 5.0 V 4) Incorporates soft-start function. 5) Incorporates timer latch system short protecting function. 6) High heat radiation surface mounted package VQFN020V4040 Application General portable equipment like portable audio or DSC/DVC Operating Conditions (Ta = 25C) Parameter Symbol Voltage range Unit Power supply voltage Vcc 2.5 to 5.5 V Output voltage OUT 2.8 to 5.2 V Absolute Maximum Ratings Parameter Symbol BD8305MUV Unit Maximum applied power voltage Vcc,PVCC 7.0 V Maximum input current Iinmax 2.0 A 7.0 Lx1 V Maximum input voltage 7.0 Lx2 V Power dissipation Pd 700 mW Operating temperature range Topr -25 to +85 C Storage temperature range Tstg -55 to +150 C Junction temperature Tjmax 150 C *1 When installed on a 70.0 mm 70.0 mm 1.6 mm glass epoxy board. The rating is reduced by 5.6 mW/C at Ta = 25C or more. * These specifications are subject to change without advance notice for modifications and other reasons. www.rohm.com 2009.05 - Rev.B 1/15 c 2009 ROHM Co., Ltd. All rights reserved. Technical Note BD8305MUV Electrical Characteristics (Unless otherwise specified, Ta = 25 C, VCC = 3.7 V) Target Value Parameter Symbol Unit Conditions Minimum Typical Maximum Low voltage input malfunction preventing circuit Detection threshold voltage VUV - 2.25 2.45 V Vcc monitor Hysteresis range VUVhy 50 100 150 mV Oscillator Oscillation frequency osc 0.8 1.0 1.2 MHz RT=47k Error AMP INV threshold voltage VINV 0.790 0.800 0.810 V Input bias current IINV -50 0 50 nA Vcc=7.0V , VINV=3.5V Soft-start time Tss 0.6 1.00 1.4 msec RT=47k Output source current IEO 10 20 30 uA VINV=0.5V , VFB =1.5V Output sink current IEI 0.7 1.5 3.0 mA VINV=1.1V , VFB =1.5V PWM comparator LX1 Max Duty Dmax1 - - 100 % LX2 Max Duty Dmax2 77 85 93 % Output LX1 PMOS ON resistance RON1p - 120 200 m VGS=3.0V LX1 NMOS ON resistance RON1n - 100 160 m VGS=3.0V LX2 PMOS ON resistance RON2p - 120 200 m VGS=3.0V LX2 NMOS ON resistance RON2n - 100 160 M VGS=3.0V LX1 OCP threshold Iocp 1.6 2.4 - A PVCC=3.0V LX1 leak current I leak1 -1 0 1 uA LX2 leak current I leak2 -1 0 1 uA STB STB pin Operation VSTBH 1.5 - 5.5 V control voltage No-operation VSTBL -0.3 - 0.3 V STB pin pull-down resistance RSTB 250 400 700 k Circuit current VCC pin ISTB1 - - 1 uA Standby current PVCC pin ISTB2 - - 1 uA VOUT pin ISTB3 - - 1 uA Circuit current at operation VCC Icc1 - 500 750 uA VINV=1.2V Circuit current at operation PVCC Icc2 - 10 20 uA VINV=1.2V www.rohm.com 2009.05 - Rev.B 2/15 c 2009 ROHM Co., Ltd. All rights reserved.