MB3871PFV-G-BND Fujitsu, MB3871PFV-G-BND Datasheet
MB3871PFV-G-BND
Related parts for MB3871PFV-G-BND
MB3871PFV-G-BND Summary of contents
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... Mobile Pentium MB3871 DESCRIPTION The FUJITSU MB3871 is a pulse width modulation (PWM) DC/DC converter IC chip that provides a selection of 1 2.0 V output voltages for Mobile Pentium The MB3871 utilizes synchronous rectification for high efficiency and features a soft-start/discharge control function for ease in designing power supplies in multi-supply systems, making it ideal for Mobile Pentium supply systems ...
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MB3871 PIN ASSIGNMENT SGND : – ENB : 7 OUT1 : OUT2 : 11 PGND : 12 2 ...
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PIN DESCRIPTION Pin no. Symbol I — Triangular wave frequency setting resistor connection pin 2 RS — Discharging resistor connection pin for soft start capacitor 3 SGND — Ground pin 4 CS — Soft start capacitor connection pin ...
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MB3871 BLOCK DIAGRAM VSENSE 20 CS Error Amp. –IN 5 – VD0 D/A 15 VD1 (4-bit) 16 VD2 17 VD3 OSC 18 TEST CT (40 pF) 4 PWRGOOD 21 POWERGOOD PWRGD ...
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OUTPUT VOLTAGE SETTING CODE VD3 VD2 VD1 ...
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MB3871 ABSOLUTE MAXIMUM RATINGS Parameter Power supply voltage V Bias voltage V Boot voltage V Control input voltage V PWRGOOD output voltage V Output current I O Peak output current I O Allowable dissipation P Storage temperature Tstg * : ...
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... No warranty is made with respect to uses, operating conditions, or combinations not represented on the data sheet. Users considering application outside the listed conditions are advised to contact their FUJITSU representative beforehand. Condition Min. — ...
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MB3871 ELECTRICAL CHARACTERISTICS Parameter Output voltage Output voltage temperature regulation Reference voltage block Input stability (Ref) Load stability Short circuit output current Threshold voltage Under voltage lockout circuit Hysteresis voltage block (UVLO) Reset voltage Soft start block Charge current (CS) ...
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Parameter PWM comparator blocks (PWM Threshold voltage Comp.1, 2) Dead time control Maximum duty cycle Dtr block (DTC) Output voltage (main side) Output blocks (Drive1, 2) Output voltage (synchronized rectifier side) Diode voltage CTL input voltage Control block (CTL) Input ...
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MB3871 (Continued) Parameter Threshold voltage Over voltage protection Hysteresis voltage comparator block (OVP) VSENSE pin input current D/A input voltage D/A (VD3 to VD0 D/A input voltage pin) (D/A) Input current Standby current General Power supply current 10 Pin Symbol ...
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TYPICAL CHARACTERISTICS Power supply current vs. Power supply voltage characteristics 5 + 4.0 3.0 2.0 1 5.0 10.0 15.0 Power supply voltage V ( vs. Temperature characteristics REF ...
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MB3871 (Continued) ERR threshold (1.3 V setting) vs. Temperature characteristics Error Amp. gain, Phase vs. Frequency characteristics –10 –20 –30 – 100 K Frequency 1. ...
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Triangular wave oscillator frequency vs. Power supply voltage characteristics 220 130 k 210 200 190 180 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 Power supply voltage V Triangular wave ...
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MB3871 FUNCTION DESCRIPTION 1. Switching Regulator Function (1) Reference voltage circuit (Ref) The reference voltage circuit uses the voltage supply from the V compensated reference voltage ( 3.5 V) for use as the reference voltage for the internal circuits of ...
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Protection Functions (1) V under voltage lockout circuit (UVLO) CC Power surges at power-on, or momentary under-voltage situations can cause abnormal operation in the MB3871, which may lead to damage or deterioration in systems. This circuit prevents abnormal operation ...
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MB3871 METHOD OF SETTING THE SOFT START TIME At startup of the MB3871, the capacitor (C start, by providing output voltage from Error Amp. that is proportional to the CS pin voltage regardless of the DC/DC converter load current. Soft ...
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PWRGOOD COMPARATOR CIRCUIT, OVP CIRCUIT OPERATION TIMING CHART CTL signal VD DC/DC VD 0.9 output voltage PWRGOOD signal OUT1 signal OUT2 signal VD 1.175 DC/DC VD 1.1 output voltage VD 0.9 PWRGOOD OUT2 VD 1.175 1.1 Hysteresis voltage 30 mV ...
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MB3871 CTL LOGIC CIRCUIT OPERATION TIMING CHART CTL signal ENB signal V output voltage REF CS pin voltage DC/DC output voltage DC/DC CONVERTER INPUT VOLTAGE (Vin) AND VB VOLTAGE SETTING The voltage at the CB pin is bootstrapped from the ...
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DC/DC CONVERTER SWITCHING OPERATION WAVEFORMS < Vin = 5V> (V) 20 OUT1 (V) OUT2 ( ...
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MB3871 APPLICATION EXAMPLE 20 signals setting voltage Output ...
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REFERENCE DATA Conversion efficiency vs Load current characteristics 100 95 90 Vin Vin 0.1 (Output voltage = 1.8 V) Vin 22 V Vin 15 V 1.0 10.0 Load ...
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MB3871 (Continued CTL 100 Transient response for CTL ON/OFF (Output = 2.0 ...
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USAGE PRECAUTIONS 1. Device settings must not exceed absolute maximum ratings. Usage under conditions exceeding absolute maximum ratings may permanently damage LSI devices. Note also that in normal operation usage within recommended operating conditions is preferred, and that the reliability ...
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... MB3871 PACKAGE DIMENSION 24-pin Plastic SSOP (FPT-24P-M03) * 7.75±0.10(.305±.004) INDEX 0.65±0.12(.0256±.0047) 7.15(.281)REF 1994 FUJITSU LIMITED F24018S-2C These dimensions do not include resin protrusion. +0.20 1.25 –0.10 (Mounting height) +.008 .049 –.004 0.10(.004) * 5.60±0.10 7.60±0.20 6.60(.260) (.220±.004) (.299± ...
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... FUJITSU sales representatives before such use. The company will not be responsible for damages arising from such use without prior approval ...