SP791EN Exar Corporation, SP791EN Datasheet
SP791EN
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SP791EN Summary of contents
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Low Power Microprocessor Supervisory Precision 4.65V Voltage Monitoring 200ms Power-OK/Reset Time Delay Independent Watchdog Time-Preset or Adjustable 75 A Maximum Operating Supply Current 1.0 A Maximum Battery Backup Current 0.1 A Maximum Battery Standby Current Power Switching 250mA Output ...
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ABSOLUTE MAXIMUM RATINGS Input Voltage (with respect to GND) VCC..................................................-0.3V to +6V VBATT.................................. ............-0.3V to +6V All Other Inputs ................-0.3V to (VOUT + 0.3V) Input Current VCC Peak..................................................... 1.0A VCC Continuous .......................................250mA VBATT Peak ..............................................250mA VBATT Continuous.......................................25mA GND, BATT ON ...
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ELECTRICAL CHARACTERISTICS (continued) (Vcc = 4.75V to 5.5V 2.8V BATT A MIN PARAMETER MIN BATT ON Output Low Voltage BATT ON Output Short Circuit Current RESET, LOW-LINE AND WATCHDOG TIMER RESET Threshold Voltage ...
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ELECTRICAL CHARACTERISTICS (continued) (Vcc = 4.75V to 5.5V 2.8V BATT A MIN PARAMETER MIN WDI Threshold Voltage 0. (Note 4) WDI Input Current POWER FAIL COMPARATOR PFI Input Threshold PFI Leakage ...
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PINOUT TOP VIEW BATT OUT Vcc 3 14 GND 4 13 Corporation BATT PFO 11 PFI 7 10 SWT 8 9 DIP/SO PIN ASSIGNMENTS Pin 1 — V — Backup-Battery ...
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TYPICAL CHARACTERISTICS V Supply Current vs. CC Temperature (Normal Mode = =2.8V 53 BATT -60 - 120 150 Temperature Deg ...
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TYPICAL CHARACTERISTICS Maximum Reset Comparator Overdrive Without Causing a Reset 100 0.1 F Capacitor V OUT 80 Above Line 60 Reset Generated 40 Below Line No Reset Generated 100 1000 Reset Threshold Voltage - V CC Chip-Enable ...
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F OTHER SYSTEM RESET SOURCES UNREGULATED SUPPLY UNREGULATED SUPPLY FAILURE Typical Operating Circuit MR RESET OUT Figure 2. Manual-Reset Timing Diagram FEATURES The SP791 is a microprocessor ( P) supervi- sory circuit that monitors ...
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RESET 10k Corporation Figure 4. Adding an external pull-down resistor ensures RESET is valid with V down to GND +5V REACTIVATE Figure 6. Two consecutive watchdog faults latch the system in reset. MR low ...
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WATCHDOG FUNCTION The watchdog monitors P activity via the Watchdog Input (WDI). If the P becomes in- active over a period of time, WDO and WDPO are asserted. To use the watchdog functon, connect WDI to a bus line or ...
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Vcc RESET THRESHOLD OUT RESET Figure 7. Reset and Chip-Enable Timing The 10ns maximum CE propagation from enables the SP791 to be used with IN OUT most Ps. CHIP-ENABLE INPUT CE is high impedance ...
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FROM REGULATED SUPPLY VOLTAGE UNREGULATED REGULATOR SUPPLY b.) Figure the unregulated supply is inaccessible, LOWLINE generates the NMI for the P. b) Use PFO to generate the P NMI if the unregulated supply is accessible. LOWLINE OUTPUT ...
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INPUT/OUTPUT STATES IN BATTERY-BACKUP MODE PIN NAME STATUS 1 V Supply current maximum BATT When V < BATT connected to V OUT OUT through an Internal PMOS switch Battery-switchover ...
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RESET THRESHOLD 200ms TYP Vcc RESET OUT SECOND CE PULSE ABSENT WHEN V Figure 11. Backup-Battery Monitor Timing Diagram LOW-BATTERY MONITOR The SP791 low-battery voltage function moni- tors V . Low-battery detection of 2.0V BATT 0.15V is ...
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Rp V OUT CE CE OUT IN Corporation GND * MAXIMUM Rp VALUE DEPENDS ON ACTIVE-HIGH CE THE NUMBER OF RAM DEVICES. MINIMUM Rp VALUE IS 1K LINES FROM LOGIC Figure 13. Alternate CE Gating Leakage current through the ...
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R1 Vcc PFI Corporation R2 GND V– +5V PFO 0V V TRIP 5 - 1.25 1. TRIP = R1 R2 NOTE NEGATIVE. TRIP Figure 15. Monitoring a Negative Voltage NEGATIVE-GOING V TRANSIENTS CC The SP791 ...
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D1 = 0.005" min. (0.127 min 0.100 BSC (2.540 BSC) ALTERNATE END PINS (BOTH ENDS) DIMENSIONS (Inches) 8–PIN Minimum/Maximum (mm) 0.115/0.195 A2 (2.921/4.953) B 0.014/0.022 (0.356/0.559) 0.045/0.070 B1 (1.143/1.778) C 0.008/0.014 (0.203/0.356) 0.355/0.400 D (9.017/10.160) E 0.300/0.325 ...
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DIMENSIONS (Inches) Minimum/Maximum 8–PIN (mm) A 0.053/0.069 (1.346/1.748) A1 0.004/0.010 (0.102/0.249 B 0.014/0.019 (0.35/0.49) D 0.189/0.197 (4.80/5.00) E 0.150/0.157 (3.802/3.988) e 0.050 BSC (1.270 BSC) H 0.228/0.244 (5.801/6.198) h 0.010/0.020 (0.254/0.498) L 0.016/0.050 (0.406/1.270) ...
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... SP791CN ................................................................................... 0˚C to +70˚C .......................................................................... 16-pin, Narrow SOIC SP791EP .................................................................................... -40˚C to +85˚C .......................................................................... 16–pin, Plastic Dip SP791EN ................................................................................... -40˚C to +85˚C ..................................................................... 16–pin, Narrow SOIC Please consult the factory for pricing and availability on a Tape-On-Reel option. Available in lead free packaging. To order, add "-L" suffix to the part number. ...