MAX791ESE Maxim Integrated Products, MAX791ESE Datasheet
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MAX791ESE
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MAX791ESE Summary of contents
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... Backup-Battery Monitor ♦ Guaranteed PART MAX791CPE MAX791CSE MAX791C/D MAX791CUE MAX791EPE MAX791ESE MAX791EJE MAX791EUE MAX791MJE * Dice are specified at T Devices in PDIP, SO and TSSOP packages are available in both Applications leaded and lead-free packaging. Specify lead free by adding the + symbol at the end of the part number when ordering. ...
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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 Low Voltage I Sink current BATT ON Output Short-Circuit Current Source current RESET, LOW-LINE, AND WATCHDOG TIMER – — ...
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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 PFI Input ...
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Microprocessor Supervisory Circuit (T = +25°C, unless otherwise noted SUPPLY CURRENT vs. TEMPERATURE CC (NORMAL OPERATING MODE +5V CC VBATT = 2.8V 54 PFI -60 -30 0 ...
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Microprocessor Supervisory Circuit (T = +25°C, unless otherwise noted.) A BATTERY CURRENT vs. INPUT SUPPLY VOLTAGE VBATT = 2.8V OUT ( ...
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Microprocessor Supervisory Circuit PIN NAME 1 VBATT Backup-Battery Input. Connect to external battery or capacitor and charging circuit. Output Supply Voltage threshold. When V OUT CC Connect a 0.1µF capacitor from Input Supply Voltage—+5V ...
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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 TRANSITION WDI DETECTOR 7 PFI 1.25V MAX791 4 GND ...
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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 The MAX791’s RESET output ensures that ...
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Microprocessor Supervisory Circuit +5V 3.6V *1µF +5V REACTIVATE *SETS Q HIGH ON POWER-UP Figure 6. Two Consecutive Watchdog Faults Latch the System in Reset Watchdog-Pulse Output As described in the preceding section, WDPO can be used as the clock input ...
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Microprocessor Supervisory Circuit V CC RESET THRESHOLD OUT 15µs 100µs RESET RESET Figure 7. Reset and Chip-Enable Timing enables the MAX791 to be used with most µPs high impedance (disabled mode) while RESET is ...
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Microprocessor Supervisory Circuit FROM REGULATED 3 2 SUPPLY OUT 0.1µF 0.1µF MAX791 1 VBATT 3.0V 15 RESET 10 LOWLINE 11 WDI GND OUT 0.1 µF VOLTAGE MAX791 1 REGULATOR VBATT ...
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Microprocessor Supervisory Circuit 1 VBATT MAX791 Figure 10. V and VBATT-to-V Switch CC OUT Battery On Output The Battery On (BATT ON) output indicates the status of the internal V /battery-switchover comparator, CC which controls the internal ...
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Microprocessor Supervisory Circuit + 1N4148 1 VBATT V OUT 0.47F MAX791 GND 4 Figure 12. SuperCap or MaxCap on VBATT Applications Information The MAX791 is not short-circuit protected. Shorting V to ground, other than power-up transients such ...
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Microprocessor Supervisory Circuit Rp* V OUT OUT MAX791 GND *MAXIMUM Rp VALUE DEPENDS ON THE NUMBER OF RAMs. MINIMUM Rp VALUE IS 1kΩ ACTIVE-HIGH CE LINES FROM LOGIC Figure 13. Alternate CE Gating Monitoring a Negative Voltage ...
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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 close to ...
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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 ______________________________________________________________________________________ Chip Topography V VBATT WDPO OUT V CC GND BATT ON PFO PFI SWT MR LOWLINE 0.07" (1.778mm) ...
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Microprocessor Supervisory Circuit (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages ...
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... 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 right to change the circuitry and specifications without notice at any time. 19 ____________________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 © 2005 Maxim Integrated Products ...