MAX791C/D MAXIM [Maxim Integrated Products], MAX791C/D Datasheet
MAX791C/D
Related parts for MAX791C/D
MAX791C/D Summary of contents
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... MaxCap or SuperCap CC Voltage Monitor for Power-Fail or Low-Battery Warning Backup-Battery Monitor – Guaranteed R ______________Ordering Information PART MAX791CPE MAX791CSE MAX791C/D MAX791EPE MAX791ESE MAX791EJE MAX791MJE * Dice are specified at T __________Typical Operating Circuit +5V 0.1 F 0.47F* OTHER SYSTEM RESET SOURCES WDPO RESET +12V ...
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Microprocessor Supervisory Circuit ABSOLUTE MAXIMUM RATINGS Input Voltage (with respect to GND) V .......................................................................-0.3V to +6V CC VBATT..................................................................-0. All Other Inputs.....................................-0. Input Current V Peak ..........................................................................1. Continuous ............................................................250mA CC VBATT Peak ..................................................................250mA VBATT ...
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Microprocessor Supervisory Circuit ELECTRICAL CHARACTERISTICS (continued 4.75V to 5.5V, VBATT = 2.8V PARAMETER I BATT ON Output SINK Low Voltage I SINK Sink current BATT ON Output Short-Circuit Current Source current RESET, LOW-LINE ...
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Microprocessor Supervisory Circuit ELECTRICAL CHARACTERISTICS (continued 4.75V to 5.5V, VBATT = 2.8V PARAMETER V WDI Threshold Voltage IH (Note WDI = 0V WDI Input Current WDI = V POWER-FAIL COMPARATOR ...
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Microprocessor Supervisory Circuit __________________________________________Typical Operating Characteristics (T = +25°C, unless otherwise noted SUPPLY CURRENT vs. TEMPERATURE CC (NORMAL OPERATING MODE +5V CC VBATT = 2.8V 54 PFI ...
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Microprocessor Supervisory Circuit ____________________________Typical Operating Characteristics (continued +25°C, unless otherwise noted.) A BATTERY CURRENT vs. INPUT SUPPLY VOLTAGE 20 VBATT = 2.8V OUT ...
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Microprocessor Supervisory Circuit ______________________________________________________________Pin Description PIN NAME 1 VBATT Backup-Battery Input. Connect to external battery or capacitor and charging circuit. Output Supply Voltage threshold. When V falls below VBATT and V OUT CC Connect a 0.1µF capacitor ...
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Microprocessor Supervisory Circuit 150mV 4.65V VBATT CHIP-ENABLE OUTPUT CONTROL OUT 9 RESET MR GENERATION TIMEBASE FOR 8 RESET AND SWT WATCHDOG WATCHDOG 11 WATCHDOG TRANSITION WDI DETECTOR 7 PFI 1.25V MAX791 4 ...
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Microprocessor Supervisory Circuit 15 RESET 10k MAX791 Figure 4. Adding an external pull-down resistor ensures – — — — — – valid with V down to GND. CC RESET Output The MAX791’s RESET output ...
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Microprocessor Supervisory Circuit +5V 3. +5V REACTIVATE *SETS Q HIGH ON POWER-UP Figure 6. Two consecutive watchdog faults latch the system in reset. dog-timeout period, WDO goes low 70ns after the falling edge of WDPO and remains low ...
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Microprocessor Supervisory Circuit V CC RESET THRESHOLD OUT 15 s 100 s RESET RESET Figure 7. Reset and Chip-Enable Timing Chip-Enable Signal Gating The MAX791 provides internal gating of chip-enable (CE) signals, to prevent erroneous data from ...
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Microprocessor Supervisory Circuit FROM REGULATED 3 2 SUPPLY OUT 0.1 F 0.1 F MAX791 1 VBATT 3.0V 15 RESET 10 LOWLINE 11 WDI GND OUT 0.1 0 VOLTAGE ...
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Microprocessor Supervisory Circuit 1 VBATT MAX791 Figure 10. V and VBATT-to-V Switch CC OUT Battery-Backup Mode The MAX791 requires two conditions to switch to bat- tery-backup mode must be below the reset CC threshold; ...
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Microprocessor Supervisory Circuit + 1N4148 1 VBATT V OUT 0.47F MAX791 GND 4 Figure 12. SuperCap or MaxCap on VBATT Low-Battery Monitor The MAX791 low-battery voltage function monitors VBATT. Low-battery detection of 2.0V ±0.15V is moni- tored ...
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Microprocessor Supervisory Circuit PFI C1* R3 MAX791 R2 PFO GND TO P +5V PFO TRIP 1.25 TRIP ...
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Microprocessor Supervisory Circuit + PFI MAX791 R2 GND V- +5V PFO 0V V TRIP 1.25 1. TRIP = R1 R2 NOTE NEGATIVE TRIP Figure 15. Monitoring a Negative Voltage Monitoring ...
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Microprocessor Supervisory Circuit START SET WDI LOW SUBROUTINE OR PROGRAM LOOP, SET WDI HIGH RETURN END Figure 17. Watchdog Flow Diagram ______________________________________________________________________________________ Watchdog Software Considerations A way to help the watchdog timer keep a closer watch on software execution involves ...
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Microprocessor Supervisory Circuit __________________Chip Topography V VBATT WDPO OUT V CC GND BATT ON PFO PFI SWT MR LOWLINE 0.07" (1.778mm) SUBSTRATE CONNECTED TO V OUT TRANSISTOR COUNT: 729 18 ______________________________________________________________________________________ RESET WDO CE IN 0.11" CE OUT (2.794mm) WDI ...
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Microprocessor Supervisory Circuit ________________________________________________________Package Information ______________________________________________________________________________________ 0° - 15° Plastic DIP PLASTIC DUAL-IN-LINE PACKAGE (0.300 in.) 0°-8° 0.101mm ...
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Microprocessor Supervisory Circuits ___________________________________________Package Information (continued Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the ...