MB3771P Fujitsu, MB3771P Datasheet
MB3771P
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MB3771P Summary of contents
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... MB3771 DESCRIPTION The Fujitsu MB3771 is designed to monitor the voltage level of one or two power supplies (+5 V and an arbitrary voltage microprocessor circuit, memory board in large-size computer, for example. If the circuit’s power supply deviates more than a specified amount, then the MB3771 generates a reset signal to the microprocessor ...
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MB3771 PIN ASSIGNMENT (TOP VIEW OUT 3 C GND 4 (DIP-8P-M01) (FPT-8P-M01) BLOCK DIAGRAM 100 Comp RESIN SB Comp (FRONT VIEW) 8 ...
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FUNCTIONAL DESCRIPTIONS Comparators Comp.A and Comp.B apply a hysteresis to the detected voltage, so that when the voltage at either the pin falls below 1.23 V the RESET output signal goes to “low” level Comp. ...
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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. 4 Rating Min ...
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ELECTRICAL CHARACTERISTICS 1. DC Characteristics Parameter Symbol Power supply current (DOWN) Detection voltage V SAH Hysterisis width Detection voltage Deviation of detection voltage Hysterisis width Input current Output voltage Output sink current CT charge current Input current Detection voltage Deviation ...
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MB3771 2. AC Characteristics Parameter Symbol input pulse width SA SB Reset hold time RESET rise time RESET fall time Propagation delay time *1: In case of V termination. SB *2: In case of V termination. SC ...
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APPLICATION CIRCUIT 1. 5V Power Supply Monitor Monitored Detection threshold voltage Power Supply Voltage Monitor (Externally Fine-Tuned Type) The V detection voltage can be adjusted externally. SA Resistance ...
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MB3771 3. Arbitrary Voltage Supply Monitor (1) Case • Detection Voltage can be set by R Detection Voltage = ( • Connect Pin when • ...
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V and 12 V Power Supply Monitor (2 types of power supply monitor V • monitored Detection voltage is about 4 • monitored When ...
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MB3771 Power Supply Monitor with forced RESET input (V RESIN is an TTL compatible input. RESIN Power Supply Monitor with Non-inverted RESET In this case, Comparator C is used to ...
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Dual (Positive/Negative) Power Supply Voltage Monitoring (V Supply) Monitors and a negative (any given level) power supply. R Detection Voltage = Example ...
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MB3771 ( Reference Voltage Generation and 5V Monitoring (No.1) Detection Voltage = 4 the above examples, the output voltage and the detection voltage are determined by the following equations: Output Voltage = ( ...
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Low Voltage and Over Voltage Detection (V V has no hysteresis. When over voltage is detected, RESET is held in the constant time as well as when SH low voltage is detected ...
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MB3771 13. Back-up Power Supply System (V • Use CMOS Logic and connect V • The back-up battery works after CS goes high as V • During t , memory access is prohibited. PO • CS‘s threshold voltage V is ...
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TYPICAL CHARACTERISTICS Power supply current vs. power supply voltage 700 600 500 Ta 400 300 200 25 C 100 Power supply voltage V Power supply current ...
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MB3771 (Continued) Detection voltage ( vs. Power supply voltage SB SC 1.27 V SBH 1. 1.25 1.24 V SBL 1.23 1.22 1.21 1. Power supply voltage V Reset hold time vs. power ...
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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 MB3771P MB3771PS MB3771PF resistors in series. Package 8-pin Plastic DIP (DIP-8P-M01) 8-pin Plastic SIP (SIP-8P-M03) 8-pin Plastic SOP ...
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... Plastic DIP (DIP-8P-M01) 4.36(.172)MAX 3.00(.118)MIN +0.30 0.99 –0 +.012 .039 –0 +0.35 0.89 –0.30 +.014 .035 –.012 1994 FUJITSU LIMITED D08006S-2C +0.40 9.40 –0.30 +.016 .370 –.012 1 PIN INDEX 6.20±0.25 (.244±.010) 0.51(.020)MIN 0.25±0.05 (.010±.002) 0.46±0.08 (.018±.003) +0 ...
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... Plastic SIP (SIP-8P-M03) INDEX-1 INDEX-2 +0.30 0.99 –0 +.012 .039 –0 2.54(.100) TYP 1994 FUJITSU LIMITED S08010S-3C-2 C +0.15 19.65 –0.35 +.006 .774 –.014 6.20±0.25 (.244±.010) 8.20±0.30 (.323±.012) 4.00±0.30 (.157±.012) +0.30 1.52 0.50±0.08 –0 +.012 (.020±.003) .060 – ...
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... INDEX 1 1.27(.050) 0.10(.004) 0.10(.004) 2002 FUJITSU LIMITED F08002S-c-6 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. ...