MB3881 Fujitsu, MB3881 Datasheet
MB3881
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MB3881 Summary of contents
Page 1
... This IC is ideal for down conversion and up/down conversion (employing a step-up/step-down Zeta system enabling free I/O setting). The MB3881 can use channel 8 as its own power supply to provide a wide range of supply voltages, allowing itself to operate at low voltage. ...
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... MB3881 PIN ASSIGNMENT GND(O)-2 1 RB8 2 DTC8 3 FB8 4 IN8 5 IN8 6 IN8(C) 7 IN8(C) 8 DTC7 9 FB7 10 IN7 11 IN7 12 DTC6 13 FB6 14 IN6 15 IN6 16 (CH5,CH6) 2 Output block Control block DTC1 FB1 IN1 DTC2 FB2 IN2 DTC3 FB3 IN3 ...
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... Error amplifier inverted input pin. I Error amplifier non-inverted input pin. I Short detection comparator input pin. I Dead time control pin. O Output pin. O Error amplifier output pin. I Error amplifier inverted input pin. I Error amplifier non-inverted input pin. I Dead time control pin. O Output pin. MB3881 (Continued) 3 ...
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... MB3881 (Continued) Pin No. Symbol 4 FB8 5 IN8 6 IN8 7 IN8 (C) CH8 8 IN8 (C) 3 DTC8 2 RB8 64 OUT8 33 RT OSC SYNC 28 CTL-1 29 CTL-2 Control 30 CTL-3 31 CTL-4 26 CSCP VCC 58 VCC ( VCC ( VSS ( VSS (O) -2 Power 52 VDD (O) 24 VREF GND 55 GND (O) -1 ...
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... GND(O)-2 C CTL CTL 29 Logic 31 CT1 1.73 V Buff 1.0 V CT2 1.73 V 0.8 1.0 V Buff CT 0 UVLO VCC Power ON/OFF 28 CTL-1 36 OSC SCP Ref (Power/CH1 CTL OFF (Standby mode) 2.5 V (64 pin VREF GND SYNC RT CT CSCP MB3881 5 ...
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... MB3881 • Enlarged view of A FB1 47 46 IN1 48 DTC1 FB2 44 IN2 43 DTC2 45 FB3 41 IN3 40 DTC3 42 FB4 38 IN4 37 DTC4 39 6 CH1 PWM Comp.1-1 Drive Error 1-1 Amp.1 PWM Comp.1-2 VB1 1.25 V SCP Drive Comp.1 1-2 1.0 V CH2 PWM Comp.2-1 Drive Error 2-1 Amp.2 PWM Comp.2-2 VB2 1.25 V SCP Drive Comp ...
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... Error Amp.6 15 IN6 0.6 V SCP Comp.6 IN6(C) 17 IN6 16 OVP 18 DTC6 13 FB7 10 Error Amp.7 IN7 11 IN7 12 1.25 V SCP Comp 1 DTC7 59 VCC(O)-2 CH5 PWM Comp.5 Drive VSS(O)-2 CH6 PWM Comp.6 Drive 61 6 CH7 PWM Comp.7 Drive 62 OUT7 7 MB3881 OUT5 OUT6 7 ...
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... MB3881 • Enlarged view of C FB8 4 Error Amp.8 IN8 5 IN8 6 SCP Comp.8 IN8(C) 7 IN8( DTC8 CTL CTL CTL-2 29 Logic CTL-3 30 CTL-4 31 Buff 0.8 Buff OSC SYNC RT 8 CH8 PWM Comp.8 Drive 8 CT1 1.73 V 1.0 V CT2 1. 0.8 V 0.3 V ...
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... IN8, IN8, IN8 (C) , IN8 (C) pin IN7 pin V CTL pin CTL SYNC pin SYNC I OUT pin O R RB8 pin B f OSC SCP Ta MB3881 Rating Unit Max 200 mA 800 125 C Value Unit Min. Typ. Max. 1 ...
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... MB3881 ELECTRICAL CHARACTERISTICS Parameter Reference voltage Output voltage temperature stability Input stability Load stability Short-circuit output current Threshold voltage Hysteresis width Reset voltage Threshold voltage Input standby voltage Charge current Threshold voltage Input standby voltage Input latch voltage Input source current ...
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... 1.35 V SINK MB3881 9 V, VSS 4.4 V, VDD 5 V) Value Unit Min. Typ. Max. 1.23 1.25 1.27 V 0.5* % 320 100 dB 1.2* MHz 2.2 2 200 mV 2.0 1.0 ...
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... MB3881 (Continued) Parameter Input offset voltage Input bias current Common mode input voltage range Voltage gain Frequency bandwidth Output voltage Output source current Output sink current Threshold voltage Input bias current Input offset voltage Input bias current Common mode input voltage range ...
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... CTL 5 V CTL 27 CTL CCS 58, 59 CTL CTL DDS CTL-1 CTL-2 I 27, 58 CTL-3 CTL-4 CTL-1 CTL CTL-3 CTL-4 MB3881 9 V, VSS 4.4 V, VDD 5 V) Value Unit Min. Typ. Max. 0.2 0.3 V 0.8 0.9 V 100 110 mA 100 mA 20 ...
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... MB3881 TYPICAL CHARACTERISTICS Power supply current vs. power supply voltage CTL 1 CTL Power supply voltage V Reference voltage vs. ambient temperature 2.56 VCC 9 V CTL 1 CTL 2 2.54 2.52 2.5 2.48 2.46 2. Ambient temperature Reference voltage vs. control voltage ...
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... T Power dissipation vs. ambient temperature 1000 CTL 800 600 400 200 100 40 20 Ambient temperature MB3881 VCC 100 pF Upper Lower 100 vs. timing resistor VCC 100 pF ...
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... MB3881 (Continued) Error amplifier gain and phase vs. frequency (CH1 100 k Frequency f (Hz) Error amplifier gain and phase vs. frequency (CH5 100 k Frequency f (Hz) Error amplifier gain and phase vs. frequency (CH8 ...
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... N-channel MOSFET (channels 1,2 synchronous rectification sides). - 1.8 V” (channels 1 to 7), allowing easy setting from CC : The comparator keeps the output transistor on while the error amplifier output voltage and DTC voltage remain higher than the triangular wave voltage. amplifier output voltage remain lower than the triangular wave voltage. MB3881 17 ...
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... MB3881 2. Channel Control Function Channels are turned on and off depending on the voltage levels at the CTL-1 terminal (pin 28), CTL-2 terminal (pin 29), CTL-3 terminal (pin 30),and CTL-4 terminal (pin 31). Voltage level at CTL pin CTL-1 CTL-2 CTL Undefined 3. Protective Functions ...
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... CS ( pin 32) CH1 to CH4, CH7 output voltage CH5, CH6 output voltage (1) (1) to (4) : CH1 to CH4, CH7 soft start interval (2) to (3) : CH8 soft start interval ) connected to the +IN8 terminal (pin 6). +IN8 1.25 V (2) (3) (4) MB3881 t 19 ...
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... MB3881 • When the CTL-2 (CTL-4) terminal is driven low (“L” level) after channels and 8 have been soft-started The capacitor (Cs) connected to the CS terminal (pin 32) starts being charged. The channel-2 (channel-7) output voltage is soft-started by the error amplifier in proportion to the CS pin voltage. ...
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... Channel 6, like channel 5, can be soft-started by connecting a capacitor between the +IN6 terminal (pin 16) and GND. SETTING THE OSCILLATION FREQUENCY The oscillation frequency can be set by connecting the timing capacitor (C timing resistor ( the RT terminal (pin 33). T Oscillation frequency 550000 f (kHz OSC C (pF MB3881 ) to the CT terminal (pin 34) and the T 21 ...
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... MB3881 SETTING THE OUTPUT VOLTAGE • CH1 to CH4 V O FB1 R1 IN1 R2 • CH5, CH6 IN5 R2 IN5(C) IN5 OVP Error Amp.1 46 1.25 V SCP Comp.1 1 Error Amp SCP 0.6 V Comp 1.25 V (R1 R2 (R1 R2 (aV > bV) ...
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... R2 12 IN7 • CH8 V O FB8 R1 IN8 R2 Ra IN8 Rb IN8(C) IN8( • IN7 V O Error Amp.7 • IN7< 1. 1.25 V SCP Comp.7 1 Error Amp SCP Comp MB3881 1.25 V 1.25 V (R1 R2) R2 IN7 (R1 R2) R2 2Rb (R1 R2) O (Ra Rb ...
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... MB3881 SAMPLE POWER SUPPLY USING CHANNEL 8 AS SELF-POWER SUPPLY Using channel 8 as the self-power supply, the MB3881 can support a wide range of supply voltages and operate at low input voltage (Vin 1.8 V). The following example shows sample power supply using a transformer. H FB8 4 5 IN8 ...
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... Output source 64 I Sink current the output circuit diagram Output source current (Peak) Output source current Output sink current (Peak) t Output current waveform MB3881 VCC (O) 2 External NPN transistor current OUT8 Output sink current RB8 0 GND ( ...
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... MB3881 SETTING TIME CONSTANT FOR TIMER-LATCH SHORT-CIRCUIT PROTECTION CIRCUIT The short detection comparator (SCP comparator) in each channel monitors the output voltage. While the switching regulator load conditions are stable on all channels, the LOG_SCP output remains at "H" level, transistor Q1 is turned on, and the CSCP terminal (pin 26) is held at “L” level. ...
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... VB 0 0.3 V “H” level Proportional 1.4 V 100 k External synchronization circuit External synchronous oscillation 0 0 SYNC MB3881 Latch1 Latch2 ...
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... MB3881 TREATMENT WITHOUT USING CSCP When you do not use the timer-latch short protection circuit, connect the CSCP terminal (pin 26) to GND with the shortest distance TREATMENT FOR KILLING THE SOFT START FEATURE To disable the channel soft start function, leave the CS terminal (pin 32) open. ...
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... When the DTC1 terminal (pin 48) is not used, connect it directly to the VREF terminal (pin 24) as shown below. (Same to other channels.) When using DTC to set dead time When no soft start time is set Rb 100[%], Vdt VREF VREF Ra 48 DTC1 Rb Vdt (Same to other channels.) 24 VREF 48 DTC1 ( Same to other channels.) MB3881 ( CH1) 29 ...
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... MB3881 APPLICATION EXAMPLE • General view 30 Vo1 (2 VCC(O)- FB1 R1 47 OUT1-1 240 C21 A 50 0.1 F C33 C1 C13 2200 pF R17 2 VSS(O)-1 46 CH1 IN1 52 R18 20 k VDD(O) 51 OUT1-2 DTC1 FB2 75 44 ...
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... CH1 VDD(O) 51 OUT1 OUT2-1 53 C14 3900 pF CH2 54 OUT2 OUT3 56 C15 3900 pF CH3 R4 75 OUT4 57 C16 3900 pF CH4 GND(O)-1 55 MB3881 Vo1 (2 240 C33 C1 C13 2200 pF 2 Vo2 (2 2 C34 C2 2 Q10 D2 Vo3 (5 ...
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... MB3881 • Enlarged view of B FB5 20 E C25 0.1 F Vin R13 R25 5 (3 IN5 R26 20 k IN5(C) 23 Motor control 22 signal IN5 DTC5 19 FB6 14 F C26 0.1 F R14 R27 IN6 R28 20 k IN6(C) 17 Motor control 16 signal IN6 R43 24 k OVP 18 R44 ...
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... RB8 GND(O)-2 1 VCC (Power/CH1 CTL OFF ( Standby mode ) (64 pin CSCP VREF GND C31 C29 100 pF 0.1 F MB3881 H C40 C42 D8 D10 Vo8 (15 V) <CCD> Vo8 D11 C43 <LCD> D12 1 F Vo8-3 C41 < ...
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... MB3881 PARTS LIST COMPONENT ITEM PNP Tr Q8 NPN Tr Q9, Q10 FET Diode D10 to D13 Diode L1 Coil L2, L3 Coil L4 Coil L5 Coil L6 Coil L7 Coil L8, L9 Coil L10, L11 Coil T1 Transformer C1 to C11 Ceramics Condensor C13 Ceramics Condensor C14 to C16 Ceramics Condensor ...
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... ORIGIN : Origin Electric Co., Ltd. TDK : TDK Corporation SUMIDA : Sumida Electric Co., Ltd. SPECIFICATION VENDOR 1/16 W MB3881 PARTS No. 35 ...
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... MB3881 REFERENCE DATA Conversion efficiency vs. load current (CH1 : Down conversion method with synchronous rectification output VCC (O) 86 VSS ( 100 150 200 250 300 350 400 450 500 Load current IL (mA) Conversion efficiency vs. load current ...
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... Load current IL (mA) Vin R3 To OUT3 75 C17 3900 pF Vin 2.5 V Vin 3 V Vin 3.6 V Vin 4.2 V Vin 6 V Vin 2.2 V Vin 1.8 V MB3881 To VDD ( C11 Iin (5 2 C39 6 2 ...
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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 MB3881PFF 38 Package 64-pin plastic LQFP (FPT-64P-M16) Remarks ...
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... FUJITSU LIMITED F64027SC-2-1 C 1.70(.067)MAX 1.40±0.10 (.055±.004) 0.10±0.10 33 (.004±.004) 32 Details of "A" part 0.10(.004) 17 "A" 16 +0.10 0.15 –0.05 +.004 .006 –.002 MB3881 (1.00(.039)) 0.50±0.25 (.020±.010) 3.5°±3.5° Dimensions in: mm (inches) 39 ...
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... MB3881 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. 3545 North First Street, ...