MB3778P Fujitsu Microelectronics, Inc., MB3778P Datasheet
MB3778P
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MB3778P Summary of contents
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FUJITSU SEMICONDUCTOR DATA SHEET ASSP Switching Regulator Controller MB3778 DESCRIPTION The MB3778 is a dual switching regulator control IC. It has a two-channel basic circuit that controls PWM system switching regulator power. Complete synchronization is achieved by using the same ...
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MB3778 PIN ASSIGNMENT DTC1 OUT1 E/GND 2 (TOP VIEW IN1 3 14 IN1 4 13 FB1 (DIP-16P-M04) (FPT-16P-M05) (FPT-16P-M06) V REF SCP CTL IN2 ...
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PIN DESCRIPTION No. Pin 1 C Oscillator timing capacitor terminal (150 pF to 15,000 pF Oscillator timing resistor terminal (5 100 1/2 voltage is also available at this pin ...
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MB3778 BLOCK DIAGRAM 9 2.46 V Reference Power 16 Voltage Supply Control 2.46 V Error Amp 2 Error Amp 1.9 V 1.3 V S.C.P. Comp 2.46 V ...
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OPERATION DESCRIPTION 1. Reference voltage circuit The reference voltage circuit generates a temperature-compensated reference voltage ( : = 2.46 V) from The reference voltage is used as an operation power supply for internal circuit. The reference is ...
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MB3778 ABSOLUTE MAXIMUM RATINGS (See NOTE) Parameter Symbol Power Supply Voltage Error Amp. Input Voltage Control Input Voltage V Collector Output Voltage V Collector Output Current Power Dissipation Operating Temperature Storage Temperature Tstg *1: The packages are mounted on the ...
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ELECTRICAL CHARACTERISTICS Parameter Reference Block Output Voltage Output Temp. Stability Input Stability Load Stability Short Circuit Output Current Under Voltage Lockout Protection Block Threshold Voltage Hysteresis Width Reset Voltage ( Protection Circuit Block (S.C.P.) Input Thresold Voltage Input ...
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MB3778 ELECTRICAL CHARACTERISTICS (Continued) Parameter Error Amp. Block Input Offset Voltage Input Offset Current Input Bias Current Common Mode Input Voltage Range Voltage Gain Frequency Band Width Common Mode Rejection Ratio Max. Output Voltage Width Output Sink Current Output Source ...
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TEST CIRCUIT 330 pF TIMING CHART (Internal Waveform) Triangular waveform oscillator output Short circuit protection comparator Reference 2.1 V input 1.9 V Dead Time, PWM input 1.6 V voltage 1.3 V Error Amp. ...
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MB3778 APPLICATION CIRCUIT • Chopper Type Step Down/inverting 820 pF 8.2 k 1.8 k 4.7 k 150 4.7 k 0.033 2.4 k 330 9 0 ...
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Chopper Type Step Up/Inverting 820 pF 8.2 k 1.8 k 4.7 k 150 4 0.033 F 4 4.7 k 330 9 0 1.8 ...
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MB3778 • Multi Output Type (Apply Transformer) 820 MB3778 0 1 150 0.033 ...
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HOW TO SET THE OUTPUT VOLTAGE The output voltage is set using the connections shown in “Connection of error Amp. Output Voltage V “Connection of Error Amp. Output Voltage V The error amplifier power is supplied by the reference voltage ...
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MB3778 HOW TO SET TIME CONSTANT FOR TIMER LATCH SHORT-CIRCUIT PROTECTION CIRCUIT Below Figure shows the configuration of the protection latch circuit. Each error amplifier output is connected to the inverting inputs of the short-circuit protection comparator and is always ...
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SETTING THE IDLE PERIOD When voltage step-up, fly-back step-up or inverted output are set, the voltage at the FB terminal may go higher than the triangular wave voltage due to load fluctuation, etc. In this case the output transistor will ...
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MB3778 SETTING THE SOFT START TIME When power is switched on, the current begins charging the capacitor (C 6). The soft start process operates by comparing the soft start setting voltage, which is proportional to the DTC1 terminal voltage, with ...
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USING THE R TERMINAL T The triangular waves, as shown in Figure “No V the oscillator frequency by charging and discharging the capacitor connected to the C value of the resistor connected to the R In addition, when voltage level ...
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MB3778 SYNCHRONIZATION OF ICs A fixed condenser and resistor are inserted in the C synchronizing by using plurality of MB3778 result, the slave ICs oscillate automatically. The R (pin 2) of the slave ICs are connected to the ...
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TYPICAL CHARACTERISTICS Power supply voltage vs. Reference voltage Ta 5.0 2 Power supply voltage V (V) CC Reference voltage vs. Temperature 2. 2.46 OR 2.45 2.44 2.43 2.42 2.41 2.40 ...
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MB3778 (Continued) Timing resistor vs. Oscillation frequency 1 M 100 15000 k100 k Timing resistor R Temperature vs. Frequency stability ...
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Frequency vs. Gain/Phase 100 Frequency f (Hz) Frequency vs. Gain/Phase (Actual Data 100 Frequency f (Hz) Actual ...
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MB3778 (Continued) Power Dissipation vs. Ambient Tem- perature (SOP) 700 620 600 500 400 300 200 100 Ambient temperature Power Dissipation vs. Ambient Tem- perature (DIP) 1100 1000 900 800 700 600 ...
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APPLICATION 1. Equivalent series resistor and stability of smoothing capacitor The equivalent series resistor (ESR) of the smoothing capacitor in the DC/DC converter greatly affects the loop phase characteristic. The stability of the system is improved so that the phase ...
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MB3778 Reference data If an aluminum electrolytic smoothing capacitor (RC 1 replaced with a low ESR electrolytic capacitor(OS CON 0.2 ), the phase margin is reduced by half(see Fig. 37 and 38). DC/DC Converter A ...
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... ORDERING INFORMATION Part number MB3778P MB3778PFV MB3778PF Package 16-pin Plastic DIP (DIP-16P-M04) 16-pin Plastic SSOP (FPT-16P-M05) 16-pin Plastic SOP (FPT-16P-M06) MB3778 Remarks 25 ...
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MB3778 PACKAGES DIMENSION 16-pin, Plastic DIP (DIP-16P-M04) INDEX-1 INDEX-2 4.36(.172)MAX 3.00(.118)MIN +0.30 0.99 –0 +.012 .039 –0 1.27(.050) MAX 1994 FUJITSU LIMITED D16033S-2C +0.20 19.55 –0.30 +.008 .770 –.012 6.20±0.25 (.244±.010) 0.51(.020)MIN (.010±.002) 0.46±0.08 (.018±.003) +0.30 1.52 –0 ...
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Plastic SSOP (FPT-16P-M05) * 5.00±0.10(.197±.004) 16 INDEX LEAD No. 1 0.65(.026) 0.10(.004) 1999 FUJITSU LIMITED F16013S-3C-5 C 0.17±0.03 (.007±.001 4.40±0.10 6.40±0.20 (.173±.004) (.252±.008) 8 "A" 0.24±0.08 0.13(.005) M (.009±.003) MB3778 Details of "A" part +0.20 1.25 ...
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MB3778 (Continued) 16-pin, Plastic SOP (FPT-16P-M06) +0.25 10.15 –0.20 INDEX 1.27(.050) TYP "A" 8.89(.350)REF 1994 FUJITSU LIMITED F16015S-2C +.010 .400 –.008 5.30±0.30 7.80±0.40 (.209±.012) (.307±.016) "B" 0.45±0.10 Ø0.13(.005) M (.018±.004) Details of "A" part 0.10(.004) 2.25(.089)MAX 0.05(.002)MIN (STAND ...
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MB3778 FUJITSU LIMITED All Rights Reserved. The contents of this document are subject to change without notice. Customers are advised to consult with FUJITSU sales representatives before ordering. The information and circuit diagrams in this document are presented as examples ...