BD8961NV ROHM Co. Ltd., BD8961NV Datasheet
BD8961NV
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BD8961NV Summary of contents
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... BD8961NV ●Description ROHM’s high efficiency step-down switching regulator BD8961NV is a power supply designed to produce a low voltage including 3.3 volts from 5 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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... OUT 4 =5→ =0→ SCP/TSD operated 2. =3.3→0V OUT OUT Current PV Current Comp Sense/ Protect SLOPE CLK Driver 6 Logic OSC UVLO 5 TSD PGND SCP 4 C ITH Fig.2 BD8961NV Block Diagram CC Input CC Output GND ...
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... Ta=25℃ 4.5 Io=2A 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 INPUT VOLTAGE:V [V] CC Fig OUT 3.35 VCC=5V 3.34 Io=0A 3.33 3.32 3.31 3.30 3.29 3.28 3.27 3.26 3.25 - 100 TEMPERATURE:Ta[℃] Fig. 6 Ta-V OUT 0.40 VCC=5V 0.35 0.30 0.25 PMOS 0.20 0.15 NMOS 0.10 0.05 0.00 - 100 TEMPERATURE:Ta[ ℃ ] Fig.9 Ta ONN ONP 1.2 Ta=25℃ 1.1 1 0.9 0.8 2.7 3.1 3.5 3.9 4.3 4.7 5.1 INPUT VOLTAGE:V [V] CC Fig. OSC V OUT 100mV ...
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... Reduces a mounting area required DC/DC Convertor Controller R ITH C ITH BD8961NV (Load response I =0.1A→0.6A OUT 160mV I OUT Fig.18 Comparison of transient response ・Output capacitor Co required for current mode control: 22μF ceramic capacitor ・Inductance L required for the operating frequency of 1 MHz: 2.2μH inductor ...
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... BD8961NV 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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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 ...
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Turns OFF the output to protect the IC from breakdown when the incorporated current limiter is activated continuously for the fixed time more. The output thus held tuned OFF may be ...
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As this IC functions with high efficiency without significant heat generation in most applications, no special consideration is needed on permissible dissipation or heat generation. In case of extreme conditions, however, including lower ...
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... L L= (ΔI : Output ripple current, and f: Switching frequency) L =0.3×2A=0.6A, for example,(BD8961NV) L =1.87μ → 2.2[μ Output capacitor should be selected with the consideration on the stability region and the equivalent series resistance required to smooth ripple voltage. Output ripple voltage is determined by the equation (4)： ...
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Selection of input capacitor (Cin Cin V OUT L Co Fig.28 Input capacitor A low ESR 22μF/10V ceramic capacitor is recommended to reduce ESR dissipation of input capacitor for better efficiency. 4. Determination of RITH, CITH that ...
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Cin , OUT OUT ITH GND,PGND R ITH C ITH Fig.31 Typical application Stable feedback loop may be achieved by canceling the pole fp (Min.) produced by the output capacitor and the load ...
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... Lay out CITH and RITH between the pins ITH and GND as near as possible with least necessary wiring. ※ SON008V5060 (BD8961NV) has thermal FIN on the reverse of the package. The package thermal performance may be enhanced by bonding the FIN to GND plane which take a large area of PCB. ● ...
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... EN ・VOUT pin OUT ・SW pin SW ・ITH pin 10kΩ ITH Fig.33 I/O equivalence circuit 13/ ...
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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 ...
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Ground wiring pattern If small-signal GND and large-current GND are provided, It will be recommended to separate the large-current GND pattern from the small-signal GND pattern and establish a single ground at the reference point of the set PCB ...
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Appendix No technical content pages of this document may be reproduced in any form or transmitted by any means without prior permission of ROHM CO.,LTD. The contents described herein are subject to change without notice. The specifications for the product ...