BD8649EFV-E2 Rohm Semiconductor, BD8649EFV-E2 Datasheet
BD8649EFV-E2
Specifications of BD8649EFV-E2
Related parts for BD8649EFV-E2
BD8649EFV-E2 Summary of contents
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... Switching Regulator with Built-in Power MOSFET BD8649EFV ●Description The BD8649EFV is a synchronous step-down switching regulator that integrates 2 low resistances N-channel MOSFETs. It achieves 3A continuous output current over a wide input supply range. Current mode operation provides fast transient response and easy phase compensation. ●Feature 1) Synchronous rectification with built-in FET type DC/DC converter 2) 3 ...
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... BD8649EFV ●Electrical characteristic (Unless otherwise noted Ta=25℃, V Parameter V supply current (operating supply current (standby) IN Reference voltage (VREF) Oscillation frequency High side FET ON resistance Low side FET ON resistance UVLO voltage SW leak current EN terminal H threshold voltage EN terminal L threshold voltage SS/DELAY terminal source current SS/DELAY – ...
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... BD8649EFV ●Reference data 0.820 VIN=12V 0.815 0.810 0.805 0.800 0.795 0.790 0.785 0.780 - [℃] Fig.1 Reference voltage – temperature 340 330 VIN=12V 320 310 300 290 280 270 260 - [℃] Fig.3 Frequency – temperature characteristic 5.0 4.8 4.6 VIN=12V 4.4 4.2 4 ...
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... BD8649EFV ●Block Diagram PSET VIN 8 VIN 9 VIN 10 ●Pin Assignment No. Symbol 1 FB Feedback terminal 2 FC Phase amends terminal Frequency adjustment resistance 3 RT connection terminal 4 PSET Adjust OFF LATCH time terminal 5 EN Enable input VIN Power supply input terminal 9 VIN Power supply input terminal ...
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... Fig.12 ON/OFF transition wave form in EN controlling 2 Soft start time set function As for BD8649EFV, output can do soft start without overshoot by charging soft start capacity (C SS/DELAY (19 pin) and GND (20 pin) terminal. Also, soft start time (tss) can be set by setting soft start capacity (C ...
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... BD8649EFV ●Protection function Protection circuit is effective for destruction prevention due to accident so that avoid using under continuous protection operation. 1 Low voltage protection function (LVP) The voltage of the terminal FB (1pin) is compared with internal reference voltage VREF terminal voltage falls below V state is fixed. Table 1 output low voltage protection function ...
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... SS terminal 6 Thermal shut down function Thermal shut down circuit (TSD circuit) is built into BD8649EFV. When the temperature of the chip exceeds Tjmax=175, the DC/DC converter is fixed in a low voltage. TSD function is aimed to shut down IC from thermal reckless driving under an abnormal state to exceed Tjmax=150. ...
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... Please select the current that flows to R1 and R2 to become much smaller than output current. 2 Soft start time setting method BD8649EFV can soft start without overshoot because of a charge current to the soft start capacitance (CSS). The soft start time can be set by connecting soft start capacity (CSS). ...
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... Moreover, please similarly have and set the margin enough to a ratings reverse-voltage for the maximum input voltage. 6 OFFLATCH time setting method If it continues abnormal state, BD8649EFV output become low voltage and state is fixed. In this case, the OFFLATCH time can be set by connecting capacitor between PSET and GND. Please select the value of OFFLATCH time according to the following expression. Please set OFFLATCH time in 200µ ...
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... BD8649EFV ●Typical application 【Condition】 VOUT = 3.3V fosc = 550kHz OFF LATCH time = 500µsec open 47k FB 1 15k FC 2 2200p 22k RT 3 27k PSET 4 2000p VIN 8 VIN 9 VIN 10 22µ www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. Softstart/Delay OSC CURRENT ...
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... BD8649EFV ●I/O equivalence circuit 1PIN(FB) VIN FB 50k Ω 4PIN(PSET) VIN 50k Ω PSET 100k Ω 2k Ω GND GND GND 17PIN(BOOT) VREG 5 BOOT SW www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved. 2PIN(FC) VIN VIN 10kΩ FC 5kΩ 400Ω 10kΩ ...
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... BD8649EFV ●Note for use 1. About the absolute maximum rating Attention is brushed off enough to the quality control likely to destroy when the absolute maximum rating such as impressed voltages (VCC_IN,DCIN) and ranges (Topr) of the operating temperature exceeded, the mode of breakings of the short or the opening, etc. cannot be specified, and examine it in this IC to give physical measures for safety such as fuses when a special mode that exceeds the absolute maximum rating is assumed ...
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... BD8649EFV ●Ordering part number Part No. Part No. HTSSOP-B20 6.5±0.1 (MAX 6.85 include BURR) (4. 0.325 S 0.08 S 0.65 +0.05 0.24 -0.04 www.rohm.com © 2010 ROHM Co., Ltd. All rights reserved Package EFV: HTSSOP-B20 <Tape and Reel information> Tape Embossed carrier tape (with dry pack) ...
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No copying or reproduction of this document, in part or in whole, is permitted without the consent of ROHM Co.,Ltd. The content specified herein is subject to change for improvement without notice. The content specified herein is for the purpose ...