BD8314NUV-E2 Rohm Semiconductor, BD8314NUV-E2 Datasheet
BD8314NUV-E2
Specifications of BD8314NUV-E2
Related parts for BD8314NUV-E2
BD8314NUV-E2 Summary of contents
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... BD8314NUV ●Description ROHM’s High-efficiency Step-up Switching Regulator Built-in Power MOSFET BD8314NUV generates step-up output including from 4 batteries, batteries such as Li1cell or Li2cell etc fixed power supply line. This IC allows easy production of small and a wide range of output current, and is equipped with an external coil/capacitor downsized by high frequency operation of 1.2 MHz, built-in 2.5 A rated 80 mΩ ...
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... BD8314NUV ●Electrical Characteristics (Unless otherwise specified °C, VCC = 7.4 V) Parameter [Low voltage input malfunction preventing circuit] Detection threshold voltage Hysteresis range [Oscillator] Oscillation frequency [Regulator] Output voltage [ERROR AMP] INV threshold voltage Input bias current Soft-start time [PWM comparator] LX Max Duty ...
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... BD8314NUV ●Description of Pins GND VCC VREG LX LX Fig.1 Pin layout ●Block Diagram VREG STB STBY_IO OSC 1.2MHz GND VREF INV www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. Pin No. 1 SWOUT 2 INV 3 STB 4～5 PGND 6～7 PGND VCC UVLO 5V REG Reference ...
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... BD8314NUV ●Description of Blocks 1. VREF This block generates ERROR AMP reference voltage. The reference voltage is 1 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 VREG pin voltage to turn off all output FET and DC/DC converter output when VREG voltage is lower than 2 ...
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... BD8314NUV ●Reference Data (Unless otherwise specified 25°C, VCC = 7.4 V) 1.02 1.01 1.00 0.99 0.98 -40 - 100 120 TEMPERATURE [ ℃ ] Fig.3. INV threshold temperature property VCC [V] Fig.6. VREG output power supply property 3.5 UVLO release 3.4 3.3 3.2 3.1 Hysteresis width 3.0 2.9 ...
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... BD8314NUV 2.5 ON 2.0 1.5 OFF 1.0 - 100 150 VCC [V] Fig.12. STB threshold temperature property - 120 TEMPARATURE [ ℃ ] Fig.15. Lx Max duty temperature property 1000 800 600 400 200 VCC [V] Fig.18. Circuit current power supply property www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. ...
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... BD8314NUV ●Example of Application Input: 3 output 500 mA 10V/500mA 22μF GRM32EB31C226KE16 (Murata) 10p ON/OFF 200k 10k 100k 22k ●Reference Application Data 1 100 VCC=10V 80 60 VCC=7.4V VCC=8. 100 1000 10000 OUTPUT CURRENT [mA] Fig.20 Power conversion efficiency Io=100mA Io=500mA INPUT VOLTAGE [V] Fig.23 Line regulation www.rohm.com © ...
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... BD8314NUV ●Reference Application Data 2 (VCC = 3.0 V, 6.0 V, 8.4 V, VOUT = 180 40 120 Phase Gain -20 -60 -40 -120 -60 -180 100 1k 10k 100k 1M 100 1000 10000 100000 1000000 Frequency [Hz] Fig.26 Frequency response property 1 (VCC = 3 200 mA) 60 180 40 120 Phase Gain -20 -60 -40 -120 -60 -180 ...
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... BD8314NUV ●Limits of the lowest power supply voltage to start up When using configuration of inputting VCC voltage from output voltage of DC/DC converter, the input voltage as power supply for the IC drops by Vf voltage of external Diode. The worst condition is shown as below. VCC terminal voltage - Vf voltage of external diode ≧ the worst voltage of UVLO reset voltage(=2.8V) Please judge this IC is useable or not considering needed start up voltage and load current ...
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... BD8314NUV ●Selection of Part for Applications (1) Inductor A shielded inductor that satisfies the current rating (current value, Ipecac as shown in the drawing below) and has a low DCR (direct resistance component) is recommended. Inductor values affect inductor ripple current, which will cause output ripple. Ripple current can be reduced as the coil L value becomes larger and the switching frequency becomes higher ...
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... Bandwidth GBW (frequency when gain is 0 dB) must be equal to or lower than 1/10 of the switching frequency. To satisfy above two items BD8314NUV incorporates phase compensation devices of R4=62 kΩ and C2=200pF. These C2 and R values decide the prim ary pole that determines the bandwidth of DC/DC converter. Primary pole point frequency 1 fp ...
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... BD8314NUV [2]Cs and Rs setting In the step-up DC/DC converter, the secondary pole point is caused by the coil and capacitor as expressed by the following equation. f ・・・・(4) LC π Duty = ( V This secondary pole causes a phase rotation of 180°. To secure the stability of the system, put zero points in 2 places to perform compensation ...
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... BD8314NUV ●I/O Equivalence Circuit FB VREG VREG VCC VCC STB VCC STB www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. INV VREG FB INV SWOUT VREG Lx, PGND VCC 13/15 Technical Note VCC VREG VCC SWOUT Lx PGND 2010.11 - Rev.C ...
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... BD8314NUV ●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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... BD8314NUV ●Ordering part number Part No. Part No. VSON010V3030 3.0±0.1 1PIN MARK 0.08 S 2.0±0.1 0.5 C0. 0.5 +0.05 0.25 -0.04 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved Package NUV: VSON010V3030 <Tape and Reel information> Tape Embossed carrier tape Quantity 3000pcs E2 S Direction ...
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