MB3825A Fujitsu Microelectronics, Inc., MB3825A Datasheet
MB3825A
Related parts for MB3825A
MB3825A Summary of contents
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... The MB3825A is an ideal device offering low power consumption, compact size and light weight for products such as self-contained camcorders and digital still cameras. ...
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... MB3825A PIN ASSIGNMENT CB2-5 1 CB1-5 2 VB5 3 OUT1-6 4 CB2-6 5 CB1-6 6 VB6 7 , OVP5 ( ( ( FB6 12 SCP CB1-2 47 VB2 46 OUT1-1 45 CB2-1 44 CB1-1 43 OUT2 VCC ( VB1 ...
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... Channel 4 error amplifier output terminal. I Channel 4 error amplifier inverted input terminal. I Channel 4 short detection comparator input terminal. Channel 4 main side output terminal. Channel 4 synchronous rectifier side output terminal. Channel 4 boot capacitor connection terminal. Channel 4 output sink current setting terminal. MB3825A (Continued) 3 ...
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... MB3825A Pin No. Symbol 17 FB5 OUT1-5 2 CB1-5 1 CB2-5 3 VB5 8 OVP5 FB6 OUT1-6 6 CB1-6 5 CB2-6 7 VB6 8 OVP5, 6 Triangular Wave Oscillator 22 CT Circuit 30 CTL1 29 CTL2 Control Circuit 13 SCP ...
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... Output circuit power supply terminal (Channel Output circuit power supply terminal (Channel 2) . Output circuit power supply terminal (Channel Reference voltage output terminal. Ground terminal. Ground terminal. Output circuit ground terminal (Channel Output circuit ground terminal (Channel MB3825A 5 ...
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... MB3825A BLOCK DIAGRAM • General view FB1 IN(E)1 IN(C)1 FB2 IN(E)2 IN(C)2 FB3 IN(E)3 CTL2 IN(C)3 DTC3 FB4 IN(E)4 IN(C)4 FB5 IN(E)5 IN(C)5 IN(E)5 FB6 IN(E)6 IN(C)6 IN(E)6 OVP5, 6 SCP CS CSCP 6 VCC(O)1, 3 <CH1> 42 CB1 Error PWM Amp.1 Comp.1 CB2-1 Drive 46 1-1 1.5 V OUT1 VB1 SCP Comp.1 Drive 43 40 1-2 OUT2-1 PWM Comp.1-2 1.5 V VCC(O)2 <CH2> ...
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... FB1 38 39 IN(E)1 1 IN(C)1 1.5 V FB2 35 Error Amp.2 36 IN(E)2 1 IN(C)2 1.5 V <CH1> Error PWM Amp.1 Comp.1-1 Drive 1 SCP Comp.1 Drive 1-2 PWM Comp.1-2 <CH2> PWM Comp.2 Drive 2 SCP Comp.2 MB3825A VCC(O) CB1 CB2-1 46 OUT1-1 41 VB1 43 OUT2-1 VCC(O)2 51 CB1 CB2-2 50 OUT1-2 47 VB2 7 ...
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... MB3825A • Enlarged view of B FB3 32 33 IN(E)3 CTL2 29 34 IN(C)3 DTC3 31 FB4 20 19 IN(E)4 18 IN(C)4 8 <CH3> Error PWM Amp.3 Comp.3 Drive 3 1.5 V SCP Comp.3 1.5 V <CH4> Error PWM Amp.4 Comp.4-1 Drive 4-1 1 SCP Comp.4 Drive 4-2 PWM Comp.4-2 1.5 V CB1 CB2-3 56 OUT1-3 52 VB3 GND(O) ...
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... V SCP <CH5> CB1-5 2 PWM Comp.5 1 CB2-5 Drive 64 5 OUT1-5 3 VB5 <CH6> CB1-6 6 PWM Comp.6 5 CB2-6 Drive 4 6 OUT1-6 7 VB6 GND(O) Comp. 0.65 V 1.35 V 0.65 V 1.35 V 0.65 V VCC 28 CTL1 Power UVLO OSC Ref 30 ON/OFF 1 VREF GND1 GND2 MB3825A 9 ...
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... MB3825A ABSOLUTE MAXIMUM RAGINGS Parameter Symbol Power supply voltage V Output current Io Output peak current Io Power dissipation P Storage temperature 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.) in excess of absolute maximum ratings. Do not exceed these ratings. ...
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... CSCP 46, 50, C 100 pF 56, 57, OSC 64, 4 46, 50, f/fdv 56, 57 64, 4 46, 50, f/fdt 56, 57 64, 4 MB3825A ( Value Unit Min Typ Max 1.485 1.500 1.515 V 0. ...
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... MB3825A Parameter Threshold voltage V temperature T stability Input bias current Voltage gain Error amplifier Frequency bandwidth block (CH1 to CH4) Maximum output voltage width Output source current Output sink current Input offset voltage Input bias current Error Common mode input amplifier voltage range ...
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... IC standby mode OFF I 30 CTL 5 V CTL 46, 50 VCC terminal CCS CTL 0 V 42, 51, VCC (O) terminal CCS O 63 CTL 0 V 28, 42 51, 63 MB3825A ( Value Unit Min Typ Max 0.55 0.60 0.65 V 400 0.9 0.55 0.65 V 1.35 1.45 V 1.0 ...
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... MB3825A TYPICAL CHARACTERISTICS Power supply current vs. power supply voltage 10 CTL1, 2 8.0 6.0 4.0 2.0 0 Power supply voltage V Reference voltage vs. power supply voltage 2 2.0 1.5 1.0 0.5 0 Power supply voltage V Reference voltage vs. control voltage 2 1.5 1.0 0.5 0 Control voltage V 14 Reference voltage vs ...
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... Timing resistor R Triangular wave upper and lower limit voltage vs. ambient temperature 1 100 pF T 1.5 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 100 Ambient temperature MB3825A Upper Lower (pF 6 100 upper lower 100 (Continued) 15 ...
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... MB3825A Duty vs. oscillator frequency (ch1) 100 6 VFB 1 100 k Oscillator frequency f Output sink current vs. output sink current setting resistor Output sink current setting resistor Duty vs ...
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... 4 180 180 90 4 4 180 Ambient temperature MB3825A 240 k 2 REF CS OUT 240 OUT 100 17 ...
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... MB3825A FUNCTIONAL DESCRIPTION 1. Switching Regulator Function (1) Reference voltage circuit The reference voltage circuit generates a temperature-compensated reference voltage ( 1.500 V) using the voltage supplied from the power supply terminal (pin 28) . This voltage is used as the reference voltage for the internal circuits of the IC. The reference voltage can also be supplied to an external device from the VREF terminal (pin 27) ...
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... The output supply monitor comparator compares the output circuit power supply (VCC ( VCC (O) 2, VCC ( the VCC level, and operates the timer-latch short protection circuit if any of the output circuit power supplies fall below Vcc 0.65 V. MB3825A connected to the CSCP terminal (pin 23) starts SCP 19 ...
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... MB3825A METHODS OF SETTING THE OUTPUT VOLTAGE Figure 1. CH1 to CH4 ( (C) 1 Figure 2. CH5 and CH6 (E (C) 5 Motor control signal IN (E) 5 OVP5 Error Amp1 1.5 V SCP Comp1 1.5 V FB5 17 Error Amp5 16 SCP 0.6 V Comp5 ...
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... Output ON base current speed-up To PWM Output OFF comparator driver Figure 4. Output current waveform Output current 0 [ VCC(O) 100 k Source current CB1 OUT1 10 k CB2 Sink current 1 60 GND (O) Speed-up current Sink current Source current (peak) t MB3825A External PNP transistor ...
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... The oscillator frequency can be set by connecting a timing capacitor (C resistor ( the RT terminal (pin 21 Oscillator frequency : f OSC 1950000 f (kHz) OSC C (pF VCC( VB1 VB3 VCC(O) 2 VB2 MB3825A VCC( VB4 VB5 VB6 ) to the CT terminal (pin 22) and a timing T RB1 RB3 RB2 RB4 RB5 RB6 ...
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... Timer-latch Q1 Q3 short circuit protection circuit connected to the CSCP terminal to charge at 1.0 A. SCP 0.7 V the SR latch is set, and the external TH bias bias Power R UVLO Ref ON/OFF MB3825A 50 mV) . STB terminal SCP External PNP transistor Output 46 stage OUT1-1 Output 43 stage OUT2-1 Output 56 stage ...
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... MB3825A TREATMENT WITHOUT USING CSCP When you do not use the timer-latch short protection circuit, connect the CSCP terminal (pin 23) to GND with the shortest distance. Figure 7. Treatment when not using CSCP 24 23 CSCP 24 GND1 25 GND2 ...
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... Amp1 39 IN (E Buff Soft Start Comp 1.5 V CSCP 23 SCP C SCP Q1 UVLO threshold CC External PNP transistor Output stage Output stage Output stage Output stage bias Power Ref UVLO ON/OFF MB3825A 46 OUT1-1 43 OUT2-1 56 OUT1-3 4 OUT1-6 29 CTL2 28 VCC 30 CTL1 27 VREF 25 ...
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... MB3825A • Channel 3 The capacitor C is placed between the DTC3 terminal (pin 31) and GND, so that when the CTL2 terminal DTC3 (pin 29) goes from “L” to “H” level, the transistor Q4 is turned off and the output voltage is in proportion to the DTC3 terminal voltage providing the soft-start operation. ...
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... If the soft-start function is not used, the CS terminal (pin 26) for channels 1, 2, and 4 should be left open. For channel 3, connect the DTC3 terminal (pin 31) to the V Figure 10. When no soft-start time is set ( channel) Open Figure 11. When no soft-start time is set (3 channel terminal (pin 27) . REF 26 CS VREF DTC3 MB3825A 27 ...
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... MB3825A METHOD OF SETTING THE DEAD TIME When the device is set for step-up inverted output based on the flyback method, the output transistor is fixed to full-on state (ON-duty 100 ) at power switch-on.To prevent this problem, you may determine the voltages on the DTC3 terminal (pin 31) from the V ON-duty) independently for each channel as shown Figure ...
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... VCC 0. CTL1 Power UVLO OSC Ref 30 ON/OFF 1 (CH1 VREF GND1 GND2 39 k 100 OFF (standby state MB3825A 1(3 6 2( 1SS196 2.2 F 750 B ...
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... MB3825A • Enlarged view ...
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... Enlarged view of B MB3825A 31 ...
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... MB3825A • Enlarged view ...
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... REFERENCE DATA Channel 1 switching operation waveform (operation at 500 kHz Synchronous rectifier length expansion 0.4 0.8 1.2 1.6 150 ns 120 ns MB3825A 100 2 ...
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... MB3825A Channel 1 main side output waveform (operation at 500 kHz (V) FB1 1.0 0.5 0 Channel 1 main side base current waveform (operation at 500 kHz (V) FB1 1.0 0 FB1 OUT1 FB1 ...
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... OUT2 (V) OUT2 Output source current peak value 30 mA Output sink current peak value 52 mA MB3825A 100 100 ...
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... Ground the workbenches, tools, and measuring equipment to earth. • Make sure that operators wear wrist straps or other appropriate fittings grounded to earth via a resistance of 250 placed in series between the human body and earth. ORDERING INFORMATION Part number MB3825APFV MB3825APFF 36 Package 64-pin plastic LQFP (FPT-64P-M03) 64-pin plastic LQFP ...
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... Details of "A" part 0.08(.003) 1.50 .059 0°~8° 17 "A" 0.50±0.20 (.020±.008) 0.60±0.15 (.024±.006) 0.08(.003) M MB3825A +0.20 –0.10 (Mounting height) +.008 –.004 0.10±0.10 (.004±.004) (Stand off) 0.25(.010) Dimensions (inches) 37 ...
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... MB3825A 64-pin Plastic LQFP (FPT-64P-M20) 9.00±0.20(.354±.008)SQ 7.00±0.20(.276±.008) INDEX 64 1 0.40(.016) 2000 FUJITSU LIMITED F64031S-1c 1.60(.063)MAX 1.40±0.10 (.055±.004) 0.10±0.10 33 (.004±.004) 32 0.10(.004) 17 "A" 16 0.16±0.03 0.127(.005) (.006±.001) Details of "A" part (1.00(.039)) 0.50± ...
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... MB3825A 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 of semiconductor device applications, and are not intended to be incorporated in devices for actual use. Also, ...