BD8964FVM-TR Rohm Semiconductor, BD8964FVM-TR Datasheet
BD8964FVM-TR
Specifications of BD8964FVM-TR
Related parts for BD8964FVM-TR
BD8964FVM-TR Summary of contents
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... BD8964FVM ●Description ROHM’s high efficiency step-down switching regulator BD8964FVM is a power supply designed to produce a low voltage including 1 volts from 5/3.3 volts power supply line. Offers high efficiency with synchronous rectifier. Employs a current mode control system to provide faster transient response to sudden change in load. ...
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... VCC 0. μ ADJ - μ ADJ 4 =4→ =0→ ADJ 3 ms SCP/TSD operated Current Comp. Current Sense Protect S + SLOPE CLK 6 OSC V CC Driver Logic UVLO 5 TSD 4 2 ITH Fig.2 BD8964FVM Block Diagram PIN function 2009.05 - Rev Input PV CC Output SW PGND GND ...
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... BD8964FVM ●Characteristics data (Reference data) 2.0 =1.5V】 【V OUT Ta=25℃ Io=0A 1.5 1.0 0.5 0 INPUT VOLTAGE:V [V] CC Fig.3 Vcc-Vout 1.55 =1.5V】 【V OUT 1.54 VCC=5V 1.53 Io=0A 1.52 1.51 1.50 1.49 1.48 1.47 1.46 1.45 -25 - TEMPERATURE:Ta[ ℃ ] Fig.6 Ta-V OUT 0 ...
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... BD8964FVM 1.2 1.1 1 0.9 0.8 4 4.5 5 INPUT VOLTAGE:V [V] CC Fig.12 Vcc-Fosc =1.5V】 【V OUT V OUT 58mV I OUT VCC=5V Ta=25℃ Fig. 15 Transient response Io=100→600mA(10μs) www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. 【V =1.5V】 OUT V = =EN V OUT VCC=5V Ta=25℃ ...
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... L required for the operating frequency of 1 MHz: 4.7μH inductor Reduces a mounting area required DC/DC Convertor Controller R ITH C ITH www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved. BD8964FVM (Load response I =0.1A→0.6A OUT 110mV I OUT Fig.17 Comparison of transient response Cin L V OUT ...
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... BD8964FVM ●Operation BD8964FVM is a synchronous rectifying step-down switching regulator that achieves faster transient response by employing current mode PWM control system. ○Synchronous rectifier It does not require the power to be dissipated by a rectifier externally connected to a conventional DC/DC converter IC, and its P.N junction shoot-through protection circuit limits the shoot-through current during operation, by which the power dissipation of the set is reduced. ○ ...
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... BD8964FVM ●Description of operations ・Soft-start function EN terminal shifted to “High” activates a soft-starter to gradually establish the output voltage with the current limited during startup, by which it is possible to prevent an overshoot of output voltage and an inrush current. ・Shutdown function With EN terminal shifted to “Low”, the device turns to Standby Mode, and all the function blocks including reference voltage circuit, internal oscillator and drivers are turned to OFF. Circuit current during standby is 0μ ...
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... BD8964FVM ●Switching regulator efficiency Efficiency ŋ may be expressed by the equation shown below: V ×I P OUT OUT OUT ×100[%]= η= Vin×Iin Pin Efficiency may be improved by reducing the switching regulator power dissipation factors P Dissipation factors resistance dissipation of inductor and FET：PD(I 2) Gate charge/discharge dissipation：PD(Gate) 3) Switching dissipation： ...
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... T ×( limit OUT Co≦ V OUT In case of BD8964FVM, for instance, and if V 1m×(2-0.8) Co≦ ≒800[μF] 1.5 Inappropriate capacitance may cause problem in startup μF to 100 μF ceramic capacitor is recommended. 3. Selection of input capacitor (Cin Cin V ...
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... BD8964FVM 4. Determination of RITH, CITH that works as a phase compensator As the Current Mode Control is designed to limit a inductor current, a pole (phase lag) appears in the low frequency area due filter consisting of a output capacitor and a load resistance, while a zero (phase lead) appears in the high frequency area due to the output capacitor and its ESR ...
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... BD8964FVM ●BD8964FVM Cautions on PC Board layout R ITH ③ C ITH For the sections drawn with heavy line, use thick conductor pattern as short as possible. ① ② Lay out the input ceramic capacitor CIN closer to the pins PVCC and PGND, and the output capacitor Co closer to the pin PGND ...
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... BD8964FVM ●Notes for use 1. Absolute Maximum Ratings While utmost care is taken to quality control of this product, any application that may exceed some of the absolute maximum ratings including the voltage applied and the operating temperature range may result in breakage. If broken, short-mode or open-mode may not be identified expected to encounter with special mode that may exceed the absolute maximum ratings requested to take necessary safety measures physically including insertion of fuses ...
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... BD8964FVM ●Ordering part number Part No. Part No. MSOP8 2.9±0.1 (MAX 3.25 include BURR) + 6° 4° −4° 1PIN MARK 0.145 0.475 S +0.05 0.22 –0.04 0.08 S 0.65 www.rohm.com © 2009 ROHM Co., Ltd. All rights reserved Package FVM:MSOP8 <Tape and Reel information> Tape ...
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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 ...