BD8305MUV Rohm, BD8305MUV Datasheet
BD8305MUV
Related parts for BD8305MUV
BD8305MUV Summary of contents
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... BD8305MUV ●Description ROHM’s 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. ...
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... BD8305MUV ●Electrical Characteristics (Unless otherwise specified °C, VCC = 3.7 V) Parameter [Low voltage input malfunction preventing circuit] Detection threshold voltage Hysteresis range [Oscillator] Oscillation frequency [Error AMP] INV threshold voltage Input bias current Soft-start time Output source current Output sink current [PWM comparator] ...
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... BD8305MUV ●Description of Pins Lx1 PGND PVCC PVCC 17 VCC 18 STB Fig. 1 Pin layout ●Block Diagram STB STBY_IO GND q FB ERROR_AMP VREF Soft Start INV www.rohm.com ○ 2010 ROHM Co., Ltd. All rights reserved. c Pin No. Pin Name ...
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... BD8305MUV ● Description of Blocks 1.VREF This block generates ERROR AMP reference voltage.The reference voltage is 0.8 V. 2.UVLO Circuit for preventing low voltage malfunction Prevents malfunction of the internal circuit at activation of the power supply voltage or at low power supply voltage. Monitors VCC pin voltage to turn off all output FET and DC/DC converter output when VCC voltage is lower than 2.2 V, and reset the timer latch of the internal SCP circuit and soft-start circuit ...
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... BD8305MUV ●Reference Data (Unless otherwise specified 25°C, VCC = 3.7 V) 0.810 0.805 0.800 VCC=7.0V VCC=5.5V VCC=3.7V VCC=2.4V 0.795 0.790 - 100 TEMPERATURE [℃] Fig.3 INV threshold 1.20 1.15 1.10 1.05 1.00 0.95 0.90 0.85 0. VCC [℃] Oscillation frequency Fig.6 (power supply property) 0 INV=0.5V -5 -10 -15 -20 -25 -30 -35 -40 0.0 0.5 1.0 1.5 FB VOLTAGE [V] FB source current Fig ...
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... BD8305MUV 300 Io=500mA 250 200 VCC=3.0V VCC=2.0V VCC=6.0V VCC=3.7V 150 100 50 0 -60 - 140 TEMPERATURE [℃] Fig.12 Lx2 Pch FET ON resistance 20 INV=1. PVCC VOLTAGE [V] Fig.15 PVCC input current 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 VCC VOLTAGE [V] Fig.18 OCP detect threshold -VCC www.rohm.com ○ ...
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... BD8305MUV ●Example of Application1 Input: 2.8 to 5.5 V, output: 3 1.0 A, frequency 600 kHz 10uF(ceramic) murata GRM31CB11A106KA01 2.8～5.5V 16 RVIN 17 18 ON/OFF 19 20 82k CVCC 1uF ●Example of Application2 Input: 2.8 to 5.5 V, output: 4 1.0 A, frequency 1MHz 10uF(ceramic) murata GRM31CB11A106KA01 2.8～5.5V RVIN ON/OFF 47k CVCC 1uF www.rohm.com ○ 2010 ROHM Co., Ltd. All rights reserved. ...
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... BD8305MUV ●Example of Board Layout VBAT VCC www.rohm.com ○ 2010 ROHM Co., Ltd. All rights reserved. c GND Lx1 CVIN L PGND Lx2 VOUT RT ↑ CFB 1pin RFB RINV2 RC CC VOUT GND Fig.21 Example of Board Layout 8/15 Technical Note www.DataSheet4U.com 2010.05 - Rev.D ...
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... BD8305MUV ●Reference Application Data (Example of application 1) 100 90 VBAT=2. VBAT=3. VBAT=4. 100 1000 OUTPUT CURRENT [mA] Fig.22 Power conversion efficiency (Example of application2) 2000 1800 1600 1400 1200 1000 800 600 400 200 0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 VBAT[V] Fig.25 Maximum output current 4.08 VBAT=3.7V 4.06 4.04 4.02 4.00 3.98 3.96 3.94 3. ...
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... BD8305MUV ●Selection of Parts for Applications (1) Output inductor A shielded inductor that satisfies the current rating (current value, Ipeak as shown in the drawing below) and has a low DCR (direct current resistance component) is recommended. Inductor values affect output ripple current greatly. Ripple current can be reduced as the coil L value becomes larger and the switching frequency becomes higher as the equations shown below. Ipeak =Iout × ...
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... BD8305MUV (4) Output voltage setting The internal reference voltage of the ERROR AMP is 0.8 V. Output voltage should be obtained by referring to Equation (8) of Fig.32. VOUT R1 INV R2 (5) Determination of phase compensation Condition for stable application The condition for feedback system stability under negative feedback is as follows: - Phase delay is 135 ° ...
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... BD8305MUV VOUT Fig.35 Example of setting of phase compensation For setting of phase-lead frequency, both of them should be put near LC resonance frequency. When GBW frequency becomes too high due to the secondary phase lead, it may get stabilized by setting the primary phase delay to a frequency slightly higher than the LC resonance frequency compensate it. ...
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... BD8305MUV ●I/O Equivalence Circuit FB VCC VOUT,Lx2,PGND VCC STB STB www.rohm.com ○ 2010 ROHM Co., Ltd. All rights reserved. c INV VCC FB INV PVCC,Lx1,PGND VOUT Lx2 PGND RT VCC Fig.36 I/O Equivalence Circuit 13/15 Technical Note www.DataSheet4U.com VCC VCC PVCC Lx1 VCC PGND VCC VCC RT 2010.05 - Rev.D ...
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... BD8305MUV ●Notes for use 1) Absolute Maximum Rating We dedicate much attention to the quality control of these products, however the possibility of deterioration or destruction exists if the impressed voltage, operating temperature range, etc., exceed the absolute maximum ratings. In addition impossible to predict all destructive situations such as short-circuit modes, open circuit modes, etc special mode exceeding the absolute maximum rating is expected, please review matters and provide physical safety means such as fuses, etc ...
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... BD8305MUV ●Ordering part number Part No. Part No. VQFN020V4040 4.0±0.1 1PIN MARK 0.08 S 2.1±0.1 C0.2 0 +0.05 0.25 1.0 -0.04 www.rohm.com ○ 2010 ROHM Co., Ltd. All rights reserved Package MUV: VQFN020V4040 <Tape and Reel information> Tape Embossed carrier tape Quantity 2500pcs ...
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... ROHM shall bear no responsibility in any way for use of any of the Products for the above special purposes Product is intended to be used for any such special purpose, please contact a ROHM sales representative before purchasing ...