MB3773 Fujitsu, MB3773 Datasheet
MB3773
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MB3773 Summary of contents
Page 1
... Watch-Dog Timer MB3773 DESCRIPTION The Fujitsu MB3773 is designed to monitor the voltage level of a power supply (+ arbitrary voltage microprocessor circuit, memory board in a large-size computer, for example. The MB3773 also contains a watch-dog timer function to detect uncontrol. Table status of processor and reset system/processor. ...
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... MB3773 PIN ASSIGNMENT RESET 2 Top View GND 4 (DIP-8P-M01) (FPT-8P-M01) ABSOLUTE MAXIMUM RATINGS Parameter Supply voltage Input voltage RESET, RESET Supply voltage Power dissipation Storage temperature NOTE: Permanent device damage may occur if the above Absolute Maximum Ratings are exceeded. Functional operation should be restricted to the conditions as detailed in the operational sections of this data sheet ...
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... Watch Dog Timer RESET Symbol Value V +3 -200 to +5 OUT t 0.1 to 1000 <100 FC 0.001 -40 to +85 a MB3773 Reference AMP . + V REF GND 4 2 RESET Unit ...
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... MB3773 ELECTORICAL CHARACTERISTICS 1) DC Characteristics ( Parameter Supply current Detection voltage Hysterisis width Reference voltage Reference voltage change rate Reference voltage output loading change rate CK threshold voltage CK input current CK input current High level output voltage Output saturation voltage Output sink current 4 Condition ...
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... Symbol I = 1. 0.2mA =VCC -0. pin - GND Condition Symbol 100pF = 2. 100pF = 2.2k = 100pF = 2.2k = 100pF MB3773 (V 5V Value Unit Min Typ Max 0.5 1.2 2.5 A CTU - 0.8 1.2 V CCL1 - 0.8 1.2 V CCL2 (V 5V Value Unit Min Typ Max T 8 ...
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... MB3773 RESET RESET GND 0. RESET 6 Fig MB3773 Basic Operation Logic Circuit T (ms (ms) WD RESET T (ms) WR RESET 0 1000 · (100ms) T 100 · (10ms · C ...
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... F T 3.0 2.0 1.0 0 1.0 Fig Detection voltage (V SH 4.50 4.44 4.30 4.20 4.10 4.00 -40 7.0 Fig Output saturation voltage vs. output sink current 500 400 300 200 100 0 2.0 4.0 MB3773 (RESET pin) Pull 2.0 3.0 4.0 5.0 6.0 7.0 Supply voltage V ( vs. temperature SL (RESET, RESET pin - 100 Temperature T ...
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... MB3773 TYPICAL CHARACTERISTIC CURVES (Continued) Fig High level output voltage vs. high level output current 5 -10 High level output current I Fig Reference voltage vs. supply voltage 1.246 1.244 1.242 1.240 1.238 1.236 1.234 0 3.0 5.0 7.0 9.0 11.0 13.0 15.0 17.0 19.0 21.0 Supply voltage V Fig Reference voltage vs. temperature 1.27 1.26 1.25 1.24 1.23 1.22 1.21 0 -40 - ...
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... - Terminal capacitance MB3773 0 100 Temperature Fig Terminal capacitance vs. watch dog timer watching time - ...
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... 3.9 9.1 3.9 10 MB3773 and MB3773 values that are sufficiently lower than the resistance of the IC’s internal Detection voltage:V (V) SL 4.4 4.1 Logic circuit RESET RESET CK GND Logic circuit RESET ...
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... MB3773 • Feeding the signal to pin RESIN and turning on Tr sets the RESET pin to Low and the RESET pin to High 10k 6 5 10k RESIN MB3773 Logic circuit RESET RESET CK GND Logic circuit RESET RESET CK GND 11 ...
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... Example : Comp. 1, Comp MB4204, MB47393 NOTE: The 5V supply voltage is monitored by the MB3773. The 12V supply viltage is monitored by the external circuit. Its output is connected to the NMI pin and, when voltage drops, Comp. 2 interrrupts the logic circuit • Use V 1 (=5V) to power the comparators (Comp. 1 and Comp the external circuit CC shown above ...
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... Comp. 1, Comp MB4204, MB47393 NOTE: When either 5V or 12V supply voltage decreases below its detection voltage (V RESET pin is set to High and the MB3773 RESET pin is set to Low. • Use V 1 (=5V) to power the comparators (Comp. 1 and Comp the external circuit shown CC above ...
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... EXAMPLE 6 : Montitoring Low voltage and Overvoltage Monitoring (with hysterisis) V (5V) CC MB3773 • Comp. 1 and Comp. 2 are used to monitor for overvoltage while the MB3773 is used to monitor for low voltage. Detection voltages the time of overvoltage are approximately 6.0V/6.1V For the formulas for finding hysterisis width and detection voltage, see section 4. • ...
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... EXAMPLE 7 : Monitoring Supply Voltage Using Delayed Trigger • Adding voltage such as shown in the figure to V width by 50 microseconds (C MB3773 increases the minimum input pulse CC = 1000pF). 1 MB3773 Logic circuit RESET RESET CK GND 15 ...
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... EXAMPLE 8 : Stopping Watch-dog Timer (Monitering only supply voltage) These are example application circuts in which the MB3773 monitors supply voltage alone without resetting the microcomputer even if the latter, used in standby mode, stops sending the clock pulse to the MB3773. •The watch-dog timer is inhibited by clamping the Cr pin voltage to V The supply voltage is constantly monitored even while the watch-dog timer is inhibited ...
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... Using NPN transistor V (5V Using PNP transistor V (5V MB3773 = =1k 2 MB3773 =51k =1k 2 MB3773 Logic circuit RESET RESET CK HALT GND Logic circuit RESET RESET CK HALT GND 17 ...
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... RESET GND (b) Standard usage and T value can be found using the following formulas reduction circuit PR 10ms 10ms 1.6ms MB3773 Logic circuit 1 8 RESET 2 7 RESET GND and Standard circuit 100ms 10ms 2.0ms ...
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... NOR Output FF3 RESET RESET CK GND C T and Q to the NOR input MB3773 V (=5V MB3773 Figure 1 Figure 2 19 ...
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... MB3773 Description of Application Circuits Using one MB3773, this application circuit monitors multiple microcomputers in one system. Signals from each microcomputer are sent to FF1, FF2 and FF3 clock inputs. Figure 2 shows these timings. Each flip-flop operates using signals sent from mi- crocomputers as its clock pulse. When even one signal stops, the relevant receiving flip-flop stops operating result, cy- clical pulses are not generated at output Q generates a reset signal ...
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... RESET RESET R =10k GND clock pulses sent from the H , the circuit generates a reset H prevents C 2 where V = 5V, T 3.0 sec sec value to be set (See the table below 10k 30 s 10k 300 s MB3773 V (5V) CC voltage 2 21 ...
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... MB3773 PACKAGE DIMENSIONS 8 pin, 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± ...
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... FUJITSU LIMITED F08002S-4C-4 C 2.25(.089)MAX 0.05(.002)MIN (STAND OFF) 5.30±0.30 7.80±0.40 (.209±.012) (.307±.016) 0.15 Ø0.13(.005) M .006 Details of "A" part MB3773 +0.40 6.80 –0.20 +.016 .268 –.008 +0.05 0.50±0.20 –0.02 +.002 (.020±.008) –.001 0.20(.008) 0.50(.020) 0.18(.007)MAX ...
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... MB3773 PACKAGE DIMENSIONS (Continued) 8 pin, 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 +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± ...
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... If any products described in this document represent goods or technologies subject to certain restrictions on export under the Foreign Exchange and Foreign Trade Control Law of Japan, the prior authorization by Japanese government should be required for export of those products from Japan. MB3773 25 ...