MB3778 Fujitsu, MB3778 Datasheet
MB3778
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MB3778 Summary of contents
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... Complete synchronization is achieved by using the same oscillator output wave. This IC can accept any two of the following types of output voltage: step-down, step-up, or voltage inversion (inverting voltage can be output to only one circuit). The MB3778’s low power consumption makes it ideal for use in portable equipment. ...
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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 FB2 DTC2 OUT2 V CC ...
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... For details, see “How to set time constant for timer latch short-circuit protection circuit”. 2.46 V reference voltage output terminal which can be obtained mA REF This pin is used to set the reference input and idle period of the error amplifiers. MB3778 Function pin. REF 3 ...
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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. Latch D.T.C. Comp 1.23 V Triangular Oscillator OUT1 7 PWM Comp1 OUT2 10 PWM Comp2 8 1 ...
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... The power control terminal (pin 14) controls power on/off modes(the power supply current in stand-by mode lower). terminal (pin 16). REF terminal. T /2) or the R terminal voltage (1. supplied to the non-inverting REF 0.65 V), the latch circuit turns the output drive transistor off BE MB3778 (pin CC with CC 5 ...
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... MB3778 ABSOLUTE MAXIMUM RATINGS 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 epoxy board (4 cm *2: The packages are mounted on the epoxy board (10 cm WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc ...
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... OSC 330 pF dev 3 bdt 100 MB3778 ( Value Unit Min Typ Max 2.41 2. 2. 120 mV 1 ...
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... MB3778 (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 Current PWM Comparator Block ...
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... Power supply voltage 3 Min. Value CTL INPUT CC TEST 4 MB3778 TEST INPUT Power “ON” Protection Enable Time t MB3778 OUTPUT 1 OUTPUT 2 DEAD TIME 100 Power “OFF” ...
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... 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 MB3778 150 330 120 H 220 (10 V) CTL 0.033 F 220 F 5 ...
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... F 4 4.7 k 330 MB3778 150 0.033 330 120 H 220 MB3778 CTL 220 3.9 k 120 H 100 220 GND ( ...
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... MB3778 • Multi Output Type (Apply Transformer) 820 MB3778 0 1 150 0.033 4.7 k 220 F 220 GND ( (10 V) CTL 220 F 1.8 k 220 1000 pF 5.6 k 220 F 220 ...
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... Connection of Error Amp. Output Voltage V V REF < 0” REF PIN 5 or PIN < REF PIN MB3778 0” and REF 13 ...
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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 compared with the reference voltage (2.1 V) connected to the non-inverting input. ...
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... Also output duty setting is required, the voltage should be set greater than the upper limit voltage of the triangular waveform, which is 1.9 V. • Setting the idle time at DTC1 (DTC2 is similar) REF 100, V (V) Rb (Ra Rb REF 16 V REF Ra 6 DTC1 MB3778 voltage as illustrated below. 15 ...
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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 the triangular waveform, and varying the ON-duty of the OUT terminal (pin 7). ...
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... terminal T Triangular wave oscillator V ( REF ) MB3778 terminal”, act to set T terminal using the current connection to external circuits REF REF REF ...
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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 V triangular wave oscillation. The C • Connection of Master, Slave 18 and R terminals of IC which becomes a master when ...
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... Triangular waveform Upper/Lower Limit voltage 6 V CTL 1 mA 2.2 2.0 1.8 1.6 1.4 1.2 Lower limit 1.0 0 100 Timing capacitor C Error Amp. Max. output voltage vs. 3 2.0 1.0 0 100 500 1 k 500 MB3778 (V) CC Upper limit (pF) T Frequency ...
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... MB3778 Timing resistor vs. Oscillation frequency 1 M 100 15000 k100 k Timing resistor R Temperature vs. Frequency stability Temperature Control voltage vs. Reference voltage 5.0 2 Control voltage V 20 Triangular waveform cycle vs ...
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... M 10 100 Frequency f (Hz) Frequency vs. Gain/Phase 470 pF 40 180 180 10 100 1 M OUT MB3778 C 0.047 F NF 180 180 100 (Actual Data) C 4700 pF NF 180 180 100 k ...
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... MB3778 (Continued) Power Dissipation vs. Ambient Temperature (SOP) 700 620 600 500 400 300 200 100 Ambient temperature Power Dissipation vs. Ambient Temperature (DIP) 1100 1000 900 800 700 600 500 400 300 200 100 Ambient temperature ...
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... V IN Gain vs. Frequency ( ( 100 1 k Frequency f (Hz) DC/DC Converter Basic Circuit Phase vs. Frequency 0 90 ( (1) 180 10 k 100 k 10 MB3778 (2) ( 100 100 k Frequency f (Hz) 23 ...
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... MB3778 2. Reference data If an aluminum electrolytic smoothing capacitor (RC TM (OS CON : RC 0.2 ), the phase margin is reduced by half(see Fig.1 and Fig.2). DC/DC Converter A FB Figure 1 DC/DC Converter 5 V output Gain vs. Phase 100 1 k Figure 2 DC/DC Converter 5 V output Gain vs. Phase ...
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... Do not apply a negative voltage - Applying a negative voltage of 0 less to an LSI may generate a parasitic transistor, resulting in malfunction. ORDERING INFORMATION Part number MB3778P MB3778PFV MB3778PF resistors in series. 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 PACKAGE DIMENSIONS 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 +.012 .060 – ...
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... Details of "A" part "A" 0.13(.005) M 0.50±0.20 (.020±.008) 0.60±0.15 (.024±.006) Dimensions in mm (inches) . Note : The values in parentheses are reference values. MB3778 +0.20 1.25 –0.10 (Mounting height) +.008 .049 –.004 0~8 ˚ 0.10±0.10 (Stand off) (.004±.004) ...
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... MB3778 (Continued) 16-pin, Plastic SOP (FPT-16P-M06) +0. 10.15 .400 –0.20 16 INDEX 1 1.27(.050) 0.10(.004) 0.10(.004) 2002 FUJITSU LIMITED F16015S-c-4 Note These dimensions include resin protrusion. Note These dimensions do not include resin protrusion. Note 3) Pins width and pins thickness include plating thickness. ...
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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, such as descriptions of function and application circuit examples, in this document are presented solely for the purpose of reference to show examples of operations and uses of Fujitsu semiconductor device ...