MB3790PFT Fujitsu, MB3790PFT Datasheet
MB3790PFT
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MB3790PFT Summary of contents
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... FUJITSU SEMICONDUCTOR DATA SHEET ASSP For Power Supply Applications Bi-CMOS Battery Backup IC MB3790 DESCRIPTION The MB3790 is designed to control power supplies to SRAM, logic IC, or other circuit devices and protects them against momentary power failures by using backup batteries. In addition to its function to supply the power to these devices, it has a function to switch the source of power to the primary or secondary backup battery when the power supply voltage drops below a predetermined level ...
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MB3790 (Continued) • On-chip power-on reset circuit • Primary battery voltage-down detection levels: 2.65 V, 2.37 V • On-chip secondary battery recharging function • Output current during battery backup: V • Leakage current: 0.5 A [Max] PIN ASSIGNMENTS (TOP VIEW) ...
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BLOCK DIAGRAM V IN CONTROL 590 k Reference voltage power 1.24 V supply circuit + - V SENSE 240 k GND R = 0.5 ON 2.65 V 500 2. ...
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MB3790 PIN DESCRIPTION Pin number Symbol 16P 20P BATI OUT BAT2 — N. ALARM1 7 9 ALARM2 8 10 GND 9 11 ...
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FUNCTIONAL DESCRIPTION 1. Battery Backup Function • When the power supply voltage exceeds the voltage detection level (i.e 200 mA from the V power supply to the load circuit via the V IN • When the power ...
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MB3790 DESCRIPTION OF OPERATION 1. Operation When the Input Voltage Goes On or Off V IN (1) V OUT RESET High level RESET Low level (1) Power-on While the power supply voltage is less than V are in the standby ...
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Momentary power failure or voltage dip When the power supply voltage drops less than or equal to V voltage dips momentarily, the RESET pin outputs a High level and the RESET pin outputs a low level. The devices such ...
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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 representatives beforehand. 8 Conditions Min – ...
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ELECTRICAL CHARACTERISTICS • DC characteristics (Recommended operating conditions unless otherwise noted.) Parameter All sections Input current Backup Input/output voltage Power difference Supply Section Output delay time Input low voltage detection Input low voltage hysteresis width Power Supply Reset output voltage ...
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MB3790 (Continued) Parameter Low voltage detection 1 Low voltage detection-1 hysteresis width Low voltage detection 2 Battery-1 Monitoring Low voltage detection-2 Section hysteresis width Low voltage detection difference Battery-1 input current Battery-1 output voltage difference during backup, CTL = GND ...
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TIMING CHART 1. Rise/Fall Times on Reset and Alarm Pins: t RESET RESET ALARM1 ALARM2 10% 2. Reset Pulse Width Input Pulse Width pdR RESET / 90% 90% 10% ...
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MB3790 3. Alarm Output delay time BAT1 ALARM1 ALARM2 4. V Output Delay Time: t OUT OUT 12 pdA 50mV V V BATL1, BATL2 50mV t pdA ro 98 ...
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TYPICAL CHARACTERISTIC CURVES 1. V characteristics of RESET pin OH 3 BAT1 2.8 2.6 2.4 2.2 2.0 0.0 -0.2 -0.4 -0.6 Current I (mA characteristics of RESET pin OH 5.0 4.8 4.6 4.4 V 4.2 ...
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MB3790 (Continued) 7. Temperature characteristics of input current -40 - Ambient temperature Temperature characteristics of power-down detection voltage 4.6 4.5 4.4 4.3 4.2 4.1 4.0 3.9 ...
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APPLICATION 1. Method of Using the CONTROL Pin It is possible to control the operation of analog switch 1 by entering a High or Low level to the CONTROL pin while being powered by the battery. The Table below shows ...
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MB3790 3. Outputting Reset Signal Forcibly The reset signal can be output forcibly by bringing the V signal is held on until the capacitor C Forced Reset Method Forced Reset Method 10k Control ...
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Adjusting the Supply Voltage Detection Level Set time The MB3790 outputs a reset signal when the power supply momentarily goes down or its voltage sags for more. The set time before this reset signal is output ...
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MB3790 STANDARD DEVICE CONFIGURATION ALARM1 ALARM2 GND *1 For C and C , use capacitors of 0.022 F or more For V and V , connect these two pins to the mating ...
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... The worker must put on a grounding device containing 250 k • 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 MB3790PF MB3790PFT resistors in series. Package 16-pin Plastic SOP (FPT-16P-M06) 20-pin Plastic TSSOP (FPT-20P-M04) ...
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... 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. Note 4) Pins width do not include tie bar cutting remainder. ...
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... Fujitsu or any third party or does Fujitsu warrant non-infringement of any third-party’s intellectual property right or other right by using such information. ...