MB3793-30A Fujitsu Media Devices, MB3793-30A Datasheet
MB3793-30A
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MB3793-30A Summary of contents
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... MB3793 DESCRIPTION The MB3793 is an integrated circuit to monitor power voltage; it incorporates a watchdog timer. A reset signal is output when the power is cut or falls abruptly. When the power recovers normally after resetting, a power-on reset signal is output to microprocessor units (MPUs). An internal watchdog timer with two inputs for system operation diagnosis can provide a fall-safe function for various applicaiton systems ...
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... MB3793 -30A PIN ASSIGNMENT PIN DESCRIPTION Pin no. Symbol 1 RESET Outputs reset pin Watchdog timer monitor time 2 CTW setting pin Power-on reset hold time set- 3 CTP ting pin 4 GND Ground pin DataSheet4U.com 2 4 DataSheet U .com (TOP VIEW RESET 2 7 CTW ...
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... CTW 2 Pulse generator 1 CK1 8 Pulse generator 2 7 CK2 DataSheet4U.com 4 DataSheet U .com of all blocks Reference Watchdog DataSheet4U.com voltage timer generator V MB3793 . 360 k Logic circuit Comp 1. REF . 240 k To GND of all blocks -30A GND 3 ...
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... Comp comparator with hysteresis to compare the reference voltage with a voltage (V of dividing the power voltage (V This function enables the MB3793 to detect an abnormality when the power is cut or falls abruptly. 2. Output circuit The output circuit contains a RESET output control comparator that compares the voltage at the CTP pin to the threshold voltage to release the RESET output if the CTP pin voltage exceeds the threshold value ...
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... CK1 V CK1 CK2 V CK2 INH I INH RESET Tstg DataSheet4U.com Symbol Conditions MB3793 (Ta Rating Unit Min Max 0 0 0 200 mW 55 125 C Value Unit Min Typ Max 1.2 3 ...
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... MB3793 -30A ELECTRICAL CHARACTERISTICS 1. DC Characteristics Parameter Power supply current Detection voltage Detection voltage hysteresis difference Clock-input threshold voltage Clock-input hysteresis Inhibition-input voltage Input current (CK1, CK2, INH) Reset output voltage Reset-output minimum power voltage * : The values enclosed in parentheses ( ) are setting assurance values. ...
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... DIAGRAM 1. Basic operation (Positive clock pulse CK1 CK2 INH V th CTP V H CTW V L RESET DataSheet4U.com 4 DataSheet U .com t CKW t CKT DataSheet4U.com (1) (2) (3) (4)(5) (5) (6) (7) MB3793 t PR (8) (9) (10) (11) (12) (13) -30A 7 ...
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... MB3793 -30A 2. Basic operation (Negative clock pulse CK1 CK2 INH V th CTP V H CTW V L RESET (1) (2) DataSheet4U.com 8 4 DataSheet U .com t CKW t CKT DataSheet4U.com (3) (4)(5) (5) (6) (7) (8) ( (10) (11) (12) (13) ...
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... V H CTW V L RESET Note : The MB3793 can monitor only one clock. The MB3793 checks the clock signal at every other input pulse. Therefore, set watchdog timer monitor time t to monitor the period twice as long as the input clock pulse. DataSheet4U.com 4 DataSheet U .com ...
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... MB3793 -30A 4. Inhibition operation (Positive clock pulse CK1 CK2 INH V th CTP V H CTW V L RESET DataSheet4U.com 10 4 DataSheet U .com t CKW DataSheet4U.com (1) (2) (3) (4)(5) (5) (6) (7) (11) (8) ( (10) (12) (13) ...
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... V H CTW V L Note : The MB3793 watchdog timer monitors Clock1 (CK1) and Clock2 (CK2) pulses alternately. When a CK2 pulse is detected after detecting a CK1 pulse, the monitoring time setting capacity (C ) switches to charging from discharging. TW When two consecutive pulses occur on one side of this alternation before switching, the second pulse is ignored ...
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... Clock monitoring To use the MB3793 while monitoring only one clock, connect clock pins CK1 and CK2. Although the MB3793 operates basically in the same way as when monitoring two clocks, it monitors the clock signal at every other input pulse. See “3. Single-clock input monitoring (positive clock pulse)” under “ DIAGRAM.” ...
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... The value with V The MB3793 repeats operations (4) and (5) as long as the CK1/CK2 pin inputs clock pulses clock pulse is input, the MB3793 repeats operations (6) and (7). ( lowered to the fall-time detected voltage (V CC MB3793 outputs a reset signal (setting the RESET pin to “L” level from “H” level). ...
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... MB3793 -30A TYPICAL CHARACTERISTICS Power supply current vs. power supply voltage 50 Watchdog timer monitoring INH Power supply voltage V Reset output voltage vs. reset output current (P-MOS side) 3.3 3.2 3.1 3.0 2.9 2.8 2.7 2.6 2.5 2.4 2 Reset output current I Note : Without writing the value clearly, VCC = 3.3 (V), CTP = 0.1 ( F), CTW = 0.01 ( F). ...
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... Ambient temperature DataSheet4U.com 4 DataSheet U .com Power-on reset hold time vs. Ambient temperature (V) CC DataSheet4U.com 100 120 MB3793 (When V rising) CC 200 3 180 160 140 120 100 100 Ambient temperature Watchdog timer monitoring time vs ...
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... MB3793 -30A (Continued) Power-on reset time vs Power-on reset time setting capacitance Watchdog timer monitoring time vs Watchdog timer monitoring time setting capacitance C DataSheet4U ...
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... APPLICATION EXAMPLE 1. (1) Supply voltage monitor and watchdog timer (1-clock monitor GND * : Use a capacitor with less leakage current. The MB3793 monitors the clock (CK1,2) at every other input pulse. (2) Supply voltage monitor and watching timer (2-clock monitor GND * : Use a capacitor with less leakage current ...
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... MB3793 -30A 2. Supply voltage monitor and watchdog timer stop GND * : Use a capacitor with less leakage current. NOTES ON USE • Take account of common impedance when designing the earth line on a printed wiring board. • Take measures against static electricity. ...
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... ORDERING INFORMATION Part number MB3793-30AP MB3793-30APF MB3793-30APNF MB3793-30APFV DataSheet4U.com 4 DataSheet U .com Package Marking 8-pin Plastic DIP 3793AN (DIP-8P-M01) 8-pin Plastic SOP 3793AN (FPT-8P-M01) 8-pin Plastic SOL 3793AN (FPT-8P-M02) 8-pin Plastic SSOP 93AN (FPT-8P-M03) DataSheet4U.com MB3793 -30A ...
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... MB3793 -30A PACKAGE DIMENSIONS 8-pin Plastic SOP (FPT-8P-M01 6. 1.27(.050) 2002 FUJITSU LIMITED F08002S-c-6-7 C DataSheet4U.com 20 4 DataSheet U .com 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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... M (.017±.003) DataSheet4U.com 0.10(.004) 0.10(.004) Dimensions in mm (inches) . Note : The values in parentheses are reference values. MB3793 -30A +0.03 0.22 –0.07 +.001 .009 –.003 Details of "A" part 1.55±0.20 (Mounting height) (.061±.008) 0.25(.010) " ...
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... MB3793 -30A 8-pin Plastic SSOP (FPT-8P-M03 3.50±0.10(.138±.004 0.80(.031) 2002 FUJITSU LIMITED F08005S-c-3-5 C DataSheet4U.com 22 4 DataSheet U .com Note Resin protrusion. (Each side : 0.15 (.006) Max) . Note These dimensions do not include resin protrusion. Note 3) Pins width and pins thickness include plating thickness. ...
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... DataSheet4U.com +.012 .060 –0 –0 +0.35 2.54(.100) –0.30 +.014 TYP –.012 Dimensions in mm (inches) . Note : The values in parentheses are reference values. MB3793 0.25±0.05 (.010±.002) 15°MAX 7.62(.300) TYP -30A 23 ...
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... MB3793 -30A 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 ...