bd9842fv ROHM Co. Ltd., bd9842fv Datasheet
bd9842fv
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bd9842fv Summary of contents
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... Switching Regulator (Controller type) BD9842FV ●Overview BD9842FV containing two circuits of switching regulator controller by pulse width modulation system. Both of two circuits can be used for step-down DC/DC converter operation. In addition, the package is designed compact, and is optimum for compact power supply for many kinds of equipment. ...
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VCC=6V unless otherwise specified) Item [VREF output unit] Output voltage Input stability Load stability Current capacity [Triangular wave oscillator] Oscillation frequency Frequency fluctuation CT source current CT sink current [Soft start unit] SS source current SS sink ...
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Single channel stop threshold voltage Standby mode setting range Slave mode setting range Active (master) mode setting range STB flow-in current [Device overall] Standby current Average power consumption * Radiation resistance design is not applied. ●Reference data ...
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Reference data 3.5 3.4 3.3 3.2 3.1 3 2.9 2.8 2.7 2.6 2.5 -50 - 100 125 Ambient Temperature: Ta(°C) Fig.7 UVLO threshold temperature characteristics 1.01 1.008 1.006 1.004 VCC=6V 1.002 1 0.998 0.996 0.994 ...
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VCC=6.0V 40 Ta=25° 1.4 1.6 1 Input Voltage: VDT(V) Fig.19 Output Duty-VDT characteristics (100kHz) 40 Ta=-40°C 35 Ta=25°C 30 Ta=85° VCC=6.0V 5 ...
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VREF VREF DT1 FB1 VREF 1V±10mV 2μA + SS1 + - SS1OFF INV1 200μ 200μA MASTER /SLAVE CT INV2 VREF 2μA - SS2 + SS2OFF + 1V±10mV FB2 DT2 CT DT2 SS2 INV2 FB2 ...
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REG (reference voltage unit) As for REG (2.5V), reference voltage (2.5V) stabilized better than supply voltage input to VCC terminal (pin 12) is supplied as an operation voltage of IC internal circuit, ...
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Soft start 1/2 (soft start function possible to provide SS terminal (pin 3 and 18) with soft start function by connecting C as shown on the right. SS Soft start time TSS is shown by the formula ...
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STB (Standby/Master/Slave function) Standby mode, slave mode, and normal (master) mode can be switched by STB terminal (pin 15). 1. When STB<0.5V, standby mode is set. Output stops (OUT=H) and REG also stops. Circuit current is also Isc = ...
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Timing chart ◎Starting characteristics (UVLO cancel) and standby operation VCC (1) UVLO (Vcc) is canceled when Vcc>3.2V. ①Vcc＞3.2VでUVLO(Vcc)解除 STB VREF起動電圧 VREF start voltage 1.8Vtyp. VREF停止電圧 VREF stop voltage 0.9Vtyp. VREF (2) UVLO (VREF) is canceled when VREF>2.2V. ②VREF＞2.2VでUVLO(VREF)解除 SS ...
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... Use in slave IC mode, STB = VREF （Slave IC） （Master IC） 2. STB OCP1- OCP1+ VCC DT1 SS1 INV1 FB1 BD9842FV DT2 SS2 INV2 FB2 GND OCP2- OCP2+ C5V Fig.37 (Vin-Vo)×Vo × Vin ESR: Equivalent serial resistance of output capacitor Co ...
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Example of overcurrent protection circuit Insert a sense resistor between the source and VIN of output Pch-FET for detecting overcurrent as shown in the figure. Refer to the formula below for determining a sense resistor and select permissible loss ...
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About board layout In order to make full use of IC performance, fully investigate the items below in addition to general precautions. ・ Each output of OCP+/OCP- is such a sensitive circuit. When wiring is routed around ...
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Precaution for use 1) About maximum absolute rating When the maximum absolute rating of application voltage or operation voltage range is exceeded, it may lead to deterioration or rupture impossible to forecast rupture in short mode or ...
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Outer dimension view BD9842 ● Order model name BD 9842 ROHM model name ? ? ? ? ? Part number Part number Lot NO Package type FV=SSOP-B20 15/15 E2 ...
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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 ...