Application example 2, Mb3878 – FUJITSU MB3878 User Manual
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MB3878
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APPLICATION EXAMPLE 2
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Amp.1> 7 VREF Amp.2> VREF Amp.3> VREF VREF VREF 5.0 V 4.2 V 1 µ A 15 2.5 V 1.5 V Bias Voltage Drive V CC (V CC − 5 V) (VCC UVLO) VCC VCC VCC CTL 215 k Ω 35 k Ω 0.91 V (0.77 V) VREF UVLO bias − INC2 OUTD FB2 VREF − INE2 + INE2 + INE1 FB1 OUTC1 − INE1 − INC1 + INC2 GND CS VCC (O) OUT Q1 Output voltage (Battery voltage) is adjustable D1 Battery VH RT − INE3 FB3 + INC1 (45 pF) R8 100 k Ω C10 5600 pF + − + − + − R9 10 k Ω R14 1.3 k Ω R10 24 k Ω R11 36 k Ω R7 22 k Ω R18 200 k Ω R17 100 k Ω C S 2200 pF R3 330 k Ω R T 47 k Ω C9 0.1 µ F C7 0.1 µ F C5 0.1 µ F C2 100 µ F C3 100 µ F C1 22 µ F R S 1 0.033 Ω R S 2 0.033 Ω L1 12 µ H R22 100 k Ω R21 100 k Ω R19 100 k Ω R20 100 k Ω R15 110 Ω R16 200 k Ω Q2 A(1/2) A(2/2) SW VIN VIN Note : SW ON : Differential Charging MODE R12 30 k Ω R13 30 k Ω C8 10000 pF A B C D System AC Adaptor VIN BATT OUTC2 R23 100 k Ω C6 1500 pF SW OFF : Dead Battery MODE Range of input voltage VIN = 13V to 21V(at Load = 3A)