MB3874 Fujitsu Media Devices, MB3874 Datasheet

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... MB3874/MB3876 DESCRIPTION The MB3874 and MB3876 are parallel 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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... MB3874/MB3876 (Continued) • Support for frequency setting using an external resistor (Frequency setting capacitor integrated) • Built-in current detector amplifier with wide in-phase input voltage range • Built-in standby current function • Built-in soft start function • Capable of parallel charging (Charging the two battery packs at a time) • ...

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... PIN ASSIGNMENT INC1 : 1 FB2 : 2 INE2 : 3 INE2 : 4 VREF : 5 CTL : 6 FB1 : 7 INE1 : 8 INE3 : 9 INE3 : 10 FB3 : 11 INC2 : 12 MB3874/MB3876 (TOP VIEW INC1 23 : GND OUT OUTM INE4 15 : FB4 14 : INE5 13 : INC2 (FPT-24P-M03) 3 ...

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... MB3874/MB3876 PIN DESCRIPTION Pin No. Symbol I/O 1 –INC1 I 2 FB2 O 3 –INE2 I 4 +INE2 I 5 VREF O 6 CTL I 7 FB1 O 8 –INE1 I 9 +INE3 I 10 –INE3 I 11 FB3 O 12 –INC2 I 13 +INC2 I 14 –INE5 I 15 FB4 O 16 –INE4 — 18 OUTM ...

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... Bias voltage block <VH> <Error Amp.4> VREF <UVLO> <Error Amp.5> 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 RT VREF : MB3874 100 k MB3876 150 k MB3874/MB3876 OUTM OUT 20 Drive 215 CTL 6 <CTL> ...

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... MB3874/MB3876 ABSOLUTE MAXIMUM RATINGS Parameter Symbol Power supply voltage Output terminal current Peak output current OUTM terminal output voltage Power dissipation Storage temperature *: 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 ...

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... THL Hysteresis width V H Charge current I CS Oscillation f OSC frequency Frequency tem- f/fdt perature stability *: Standard design value. (MB3874 : (MB3876 : Conditions Min +25°C 4.167 –30°C to +85°C 4.158 — VREF = –1 mA — ...

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... V Frequency BW bandwidth V FBH Output voltage V FBL Output source I SOURCE current Output sink I SINK current *: Standard design value. 8 (MB3874 : (MB3876 : Conditions Min. FB1 = 2 V, 14.00 –INE1 = 2. FB1 = 2 V, 16.80 –INE1 = 2. –INE1 –100 7 DC — — ...

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... Output voltage V FBL Output source I SOURCE current Output sink I SINK current *: Standard design value. (MB3874 : (MB3876 : Conditions Min. 12.500 12.600 12.700 FB4 = +25 C 16.666 16.800 16.934 1, 12 12.474 12.600 12.726 FB1 = – +85 C 16.632 16.800 16.968 – ...

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... TLH Threshold voltage V THL Hysteresis width V H Output leak current I LEAK Output voltage (MB3874 : (MB3876 : 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= 0.1 V, 13, 24 –130 –INC1= –INC2 +INC1= +INC2=12.7 V, 2.25 – ...

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... CTL input voltage V OFF I CTLH Input current I CTLL Output voltage VH Standby current I CCS Power supply I CC current *: Standard design value (MB3874 : (MB3876 : Pin No. Conditions Min. OUT = 11 V, Duty 5 % — 1/fosc Duty ) 20 OUT = 14 V, Duty 5 % — 1/fosc Duty ) ...

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... VREF Power supply voltage V ( (MB3874 (MB3876) CC CTL 5 V VREF 100 Ambient temperature (MB3874 (MB3876 CTL pin voltage V (V) CTL (Continued) ...

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... Power supply voltage V Error amplifier threshold voltage vs. 5 (MB3874) 4 (MB3876 3 2.0 1.0 0.0 1.0 2.0 3.0 4 100 5 Ambient temperature MB3874/MB3876 power supply voltage CTL (V) CC ambient temperature (MB3874 (MB3876) CC CTL 100 13 ...

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... V 90 180 100 100 (MB3874 (MB3876) CC 240 2 OUT (10) 2 (11 (9) Error Amp.2 2.088 V (Error Amp. (MB3874 (MB3876 100 k (13) OUT 3 25 (10) 1 (12) Current Amp.1 (Current Amp.2) MB3874 12.6 V MB3876 16.8 V ...

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... PWM control signal. The error amplifier inverted 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 MB3874 and MB3876 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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... MB3874/MB3876 (RS2) using the +INC2 terminal (pin 13) and INC2 terminal (pin 12) and output the signal amplified by 25 times to the error amplifier (Error Amp the next stage. (7) PWM comparator block (PWM Comp.) The PWM comparator circuit is a voltage-pulse width converter for controlling the output duty of the error amplifiers (Error Amp ...

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... IC enters the constant-power mode to reduce the charge current in order to keep AC adapter power constant. AC adapter detected voltage setting Vth Vth (V) = (208k + 42k) / 42k INE1 : = 5.95 INE1 setting voltage range : 1.176 V to 4.2 V (equivalent for Vcc) INE1 OSC INE1 <Error Amp.1> 208 MB3874/MB3876 ) connected the RT terminal (pin 17 ...

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... L: Dynamically-controlled charging H: C.V.C.C (constant-voltage/constant-current charging control standby mode Adaptor 18 Constant current control Battery Charger Ichg Mode MB3874 Signal MB3876 Battery 2.8 V 2 adapter dynamically- controlled charging ISYS System Power ...

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... D2) and between the sense resistors (Rs Pay attention to the voltage/current characteristics of the reverse-current preventive diode (D1, D2) not to let it exceed the overcharge stop voltage MB3874/MB3876 VIN (16 V/ pin to 1 pin A ...

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... 0.075 100 F 100 Battery 1 D1 Pin 13 Pin 215 BATT2 0.075 D3 Battery 2 CTL MB3874 100 k 23 MB3876 150 MB3874 22 k MB3876 MB3874 16 V MB3876 MB3874 12.6 V MB3876 16.8 V ...

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... R13 Resistor R14, R15 Resistor R16, R17 Resistor R18, R19 Resistor Note: VISHAY SILICONIX : VISHAY Intertechnology, Inc. MOTOROLA : Motorola Japan Ltd. ROHM : RHOM CO., LTD SUMIDA : SUMIDA ELECTRIC CO., Ltd. MB3874/MB3876 SPECIFICATION VENDOR Si4435DY VISHAY SILICONIX 2N7002 VISHAY SILICONIX MBRS130LT3 MOTOROLA RB151L-40F ROHM ...

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... MB3874/MB3876 REFERENCE DATA MB3874 • Conversion efficiency vs. charge current (Fixed voltage mode) 100 charge voltage = 12.6V, BATT1 f = 286.37kHz, BATT2 = OPEN 98 OSC %)=( )/( BATT1 BATT1 96 94 Vin 100 m BATT1 charge current I Conversion efficiency vs. charge current (Fixed voltage mode) ...

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... BATT2 = OPEN BATT1 ( CTL ( 120 DC/DC converter switching waveforms OUT ( 160 200 t (ms) MB3874/MB3876 Vin = 286.7 kHz OSC Load : BATT1 = 1A BATT2 = OPEN ...

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... MB3874/MB3876 MB3876 • Conversion efficiency vs.charge current (Fixed voltage mode) 100 BATT1 charge voltage =16.8V 282.71kHz, BATT2 = OPEN, 98 OSC %)=(V I BATT1 BATT1 96 94 Vin 100 m BATT1 charge current I Conversion efficiency vs.charge current (Fixed voltage mode) 100 Parallel charging, BATT1 Charge voltage =16 282 ...

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... Soft start operating waveforms Vin = 19 V Load : BATT1 = 50 INE1 = 0 V BATT2 = OPEN 10 V BATT1 (V) 20 CTL ( 120 MB3874/MB3876 DC/DC converter switching waveforms 5 V OUT ( 160 200 (ms) Vin = 282.6 kHz OSC Load : BATT1 = 1 A ...

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... Working personnel should be grounded with resistance of 250 between body and ground not apply negative voltages. The use of negative voltages below –0.3 V may create parasitic transistors on LSI lines, which can cause abnormal operation ORDERING INFORMATION Part number MB3874PFV MB3876PFV 26 Package 24-pin plastic SSOP (FPT-24P-M03) ...

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... 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 MB3874/MB3876 * : These dimensions do not include resin protrusi +0.20 1.25 +0.20 –0.10 1.25 (Mounting height) –0.10 +.008 (Mounting height) .049 +.008 – ...

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... MB3874/MB3876 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 ...