MB3875 Fujitsu Media Devices, MB3875 Datasheet

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... MB3875/MB3877 DESCRIPTION The MB3875 and MB3877 are charging DC/DC converter ICs suitable for down-conversion, which uses pulse width modulation (PWM) for controlling the output voltage and current independently. These ICs can dynamically control the secondary battery’s charge current by detecting a voltage drop adapter in order to keep its power constant (dynamically-controlled charging) ...

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... MB3875/MB3877 (Continued) • Support for frequency setting using an external resistor (Frequency setting capacitor integrated) • On-chip current detector amplifier with wide in-phase input voltage range • On-chip standby current function • On-chip soft start function • Internal totem-pole output stage supporting P-channel MOS FETs devices ...

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... PIN ASSIGNMENT INC2 : 1 IN3 : 2 FB2 : 3 OUTC2 : 4 VREF : 5 INE2 : 6 INE2 : 7 INE1 : 8 FB1 : 9 OUTC1 : 10 INE1 : 11 INC1 : 12 MB3875/MB3877 (TOP VIEW INC2 23 : GND OUT INE3 15 : FB3 14 : CTL 13 : INC1 (FPT-24P-M03) (O) 3 ...

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... MB3875/MB3877 PIN DESCRIPTION Pin No. Symbol I/O 1 –INC2 I 2 IN3 I 3 FB2 O 4 OUTC2 O 5 VREF O 6 –INE2 I 7 +INE2 I 8 +INE1 I 9 FB1 O 10 OUTC1 O 11 –INE1 I 12 –INC1 I 13 +INC1 I 14 CTL I 15 FB3 O 16 –INE3 — — ...

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... V CC Bias voltage block <VH> <UVLO> <Error Amp.3> VREF (V UVLO) CC 0.91 V VREF (0.77 V) (4.2 V) VREF ULVO bias 2.5 V 1.5 V <OSC> <REF> (45 pF GND VREF : MB3875 100 k MB3877 150 OUT Drive 215 CTL 14 <CTL> ...

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... MB3875/MB3877 ABSOLUTE MAXIMUM RAGINGS Parameter Symbol Power supply voltage V Output current I OUT Peak output current I OUT Power dissipation P Storage temperature Tstg *: The package is mounted on the dual-sided epoxy board (10 cm WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings. ...

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... V THL Hysteresis width V H Charge current I CS Oscillation f OSC frequency Frequency tem- f/f dT perature stability *: Standard design value. (MB3875 : (MB3877 : Conditions Min +25°C 4.167 –30°C to +85°C 4.158 — VREF = –1 mA — ...

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... R 2 Voltage gain A V Frequency BW bandwidth V FBH Output voltage V FBL Output source I SOURCE current Output sink I SINK current *: Standard design value. 8 (MB3875 : (MB3877 : Conditions Min. 6,7,8,11 FB1 = FB2 = 2 V 6,7,8,11 — –100 6,7,8,11 — 3 3,9 — 3,9 — 3,9 FB1 = FB2 = 2 V 3,9 ...

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... V OUTCH Output voltage V OUTCL Output source I SOURCE current Output sink I SINK current *: Standard design value. (MB3875 : (MB3877 : Pin No. Conditions Min. +INC1= +INC2=12.7 V — –INC1= –INC2=12.6 V 13, 24 +INC1= +INC2=16.9 V — –INC1= –INC2=16.8 V +INC1= +INC2=12.7 V — –INC1= –INC2=12 +INC1= +INC2=16 ...

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... Output sink current Output ON resistor Rise time Fall time CTL input voltage Input current Output voltage Standby current Power supply current *: Standard design value. 10 (MB3875 : (MB3877 : Pin No. Conditions V 3,9,15 Duty cycle = 3,9,15 Duty cycle = 100 % TH OUT = 11 V Duty ...

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... CTL pin current vs. CTL pin voltage Control pin voltage V MB3875/MB3877 CTL 5 V VREF ( (MB3875 (MB3877) CC CTL 5 V VREF 100 (MB3875 (MB3877 ...

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... V (MB3875 (MB3877) 4.0 CC CTL 2.0 1.0 0.0 1.0 2.0 3.0 4.0 5 100 40 power supply voltage CTL Power supply voltage V (V) CC ambient temperature (MB3875 (MB3877) CC CTL 100 Ambient temperature ...

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... 180 90 (13) 0 0.1 V (12) 90 MB3875 12.6 V MB3877 16.8 V 180 100 100 MB3875/MB3877 (MB3875 (MB3877) CC 240 k 11 OUT (6) 9 (3) 8 (7) 2.088 (MB3875 (MB3877 100 k OUT 4 25 (10) 1 Current Amp ...

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... The error amplifier inverting input pin is connected to the output voltage setting resistor in the IC, eliminating the need for an external resistor for setting the output voltage. The MB3875 and MB3877 are set to output voltage of 12.6 V (for a 3-cell battery) and 16.8 V (for a 4-cell battery), respectively; these ICs are suitable for use in equipment that uses a lithium-ion battery ...

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... Soft Start Function Soft start block (SOFT) Connecting a capacitor to the CS terminal (pin 22) prevents surge currents when the IC is turned on. Using an error amplifier for soft start detection makes the soft start time constant, independent of the output load of the DC/DC converter. MB3875/MB3877 15 ...

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... MB3875/MB3877 METHOD OF SETTING THE CHARGING CURRENT The charge current (output control current) value can be set with the voltage at the +INE2 terminal current exceeding the set value attempts to flow, the charge voltage drops according to the set current value. Battery charge current setting voltage ...

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... INE1 setting voltage range : 1.176 V to 4.2 V (equivalent for Vcc) INE1 INE1 R2 OPERATION TIMING DIAGRAM Error Amp.2 FB2 Error Amp.3 FB3 Error Amp.1 FB1 OUT Constant voltage AC adapter dynamically- control controlled charging <Error Amp.1> Constant current control MB3875/MB3877 2 adapter dynamically- controlled charging 17 ...

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... MB3875/MB3877 NOTE ON AN EXTERNAL REVERSE-CURRENTPREVENTIVE DIODE Insert a reverse-current preventive diode (D) at one of the three locations marked * to prevent reverse current from the battery. Pay attention to the voltage/current characteristics of the reverse-current preventive diode (D) not to let it exceed the overcharge stop voltage. 18 VIN (16 V/ (O) ...

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... OUT BATT 0.033 C2 C3 100 F 100 0.1 F CTL MB3875 100 k MB3877 150 Vin = Vin = MB3875 16 V/19 V MB3877 MB3875 12.6 V MB3877 16 ...

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... MB3875/MB3877 PARTS LIST COMPONET ITEM QI FET Q2 FET D1 Diode L1 Coil C1 OS Condensor C2 OS Condensor C3 OS Condensor C Ceramics Condensor S C5 Ceramics Condensor C6 Ceramics Condensor C7 Ceramics Condensor C8 Ceramics Condensor C9 Ceramics Condensor C10 Ceramics Condensor R Resistor S R Resistor T R3 Resistor R4 Resistor R5 Resistor R6 Resistor R7 Resistor R8 Resistor ...

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... DCC MODE Dead Battery MODE (A) BATT charge current I BATT MB3875/MB3877 (Fixed current mode) BATT= Electronic load (Product of KIKUSUI PLZ-150W) Vin Vin BATT charge voltage V (V) BATT Vin=19v ...

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... MB3875/MB3877 (Continued) Soft start operating waveforms Vin = 16 V Load : BATT = 20 INE1 = 0 V BATT ( CTL ( Soft start operating waveforms Vin = 19 V Load : BATT = 20 INE1 = 0 V BATT ( CTL ( ...

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... Iin) 100 Vin (A) BATT charge voltage V BATT Vin=19v BATT:Electronic load (Product of KIKUSUI PLZ-150W) DCC MODE (A) BATT MB3875/MB3877 BATT= Electronic load (Prouct of KIKUSUI PLZ-150W) Vin (V) BATT 23 ...

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... MB3875/MB3877 (Continued) Soft start operating waveforms Vin = 19 V Load : BATT = 50 INE1 = BATT (V) 20 CTL ( DC/DC converter switching waveforms OUT ( 120 160 200 t (ms) Vin = 287.4 kHz OSC Load : BATT = 2 A ...

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... After mounting, printed circuit boards should be stored and shipped in conductive bags or containers. • Work platforms, tools, and instruments should be properly grounded. • Working personnel should be grounded with resistance of 250 between body and ground. ORDERING INFORMATION Part number MB3875PFV MB3877PFV MB3875/MB3877 Package 24-pin plastic SSOP (FPT-24P-M03) Remarks 25 ...

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... MB3875/MB3877 PACKAGE DIMENSION 24-pin plastic SSOP (FPT-24P-M03) * 7.75±0.10(.305±.004) * 7.75±0.10(.305±.004) INDEX INDEX 0.65±0.12(.0256±.0047) 0.65±0.12(.0256±.0047) 7.15(.281)REF 7.15(.281)REF 1994 FUJITSU LIMITED F24018S-2C-2 1994 FUJITSU LIMITED F24018S-2C :These dimensions do not include resin protrusion. ...

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... MB3875/MB3877 FUJITSU LIMITED For further information please contact: Japan FUJITSU LIMITED Corporate Global Business Support Division Electronic Devices KAWASAKI PLANT, 4-1-1, Kamikodanaka Nakahara-ku, Kawasaki-shi Kanagawa 211-8588, Japan Tel: 81(44) 754-3763 Fax: 81(44) 754-3329 http://www.fujitsu.co.jp/ North and South America FUJITSU MICROELECTRONICS, INC. Semiconductor Division ...