MAX815 Maxim Integrated Products, MAX815 Datasheet
MAX815
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MAX815 Summary of contents
Page 1
... Reset thresholds are available for operation with a vari- ety of 3V and 5V supply voltages. A 75µA maximum supply current makes the MAX814/ MAX815/MAX816 ideal for use in portable equipment. All three devices are available in 8-pin DIP and SO packages. See the Selector Table below for a review of features ...
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... Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS, +5V Parts (MAX814/MAX815K 4.85V to 5.5V for MAX814K/MAX815K, V ...
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... MR to RESET Out Delay t MD PFI Input Threshold V PFI PFI Input Current I PFI LOW LINE, PFO, WDO Assertion Delay ELECTRICAL CHARACTERISTICS, +3V Parts (MAX814/MAX815T, MAX816 3.06V to 5.5V for MAX814T/MAX815T and MAX816 PARAMETER SYMBOL Operating Voltage Range V CC Supply Current I SUPPLY Reset Threshold V RT ...
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... Accuracy, Low-Power, +3V and +5V µP Supervisory Circuits ELECTRICAL CHARACTERISTICS, +3V Parts (MAX814/MAX815T, MAX816) (continued 3.06V to 5.5V for MAX814T/MAX815T and MAX816 PARAMETER SYMBOL WDI Pulse Width t WP WDI Input Threshold V WDI WDI Input Current I WDI MR to WDO High Delay t WDO LOW LINE to RESET Differential ∆ ...
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... RESET TIMEOUT PERIOD vs. TEMPERATURE 200 195 V = 3.3V CC 190 185 V = 5.0V 180 CC 175 -60 -40 - 100 TEMPERATURE (°C) PFI THRESHOLD vs. TEMPERATURE 5V PARTS (MAX814/MAX815K 2.550 2.540 2.530 2.520 2.510 2.500 2.490 2.480 2.470 2.460 2.450 -60 -40 - 100 TEMPERATURE (°C) LOW-LINE COMPARATOR PROPAGATION DELAY vs. TEMPERATURE 60 ...
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... RESET COMPARATOR OVERDRIVE (mV _______________________________________________________________________________________ RESET THRESHOLD DEVIATION vs. TEMPERATURE 5V PARTS (MAX814/MAX815K -60 -40 - 100 MAXIMUM TRANSIENT DURATION vs. RESET COMPARATOR OVERDRIVE 5V PARTS (MAX814/MAX815K 140 120 100 80 RESET OCCURS ABOVE CURVE RESET COMPARATOR OVERDRIVE (mV 100 TEMPERATURE (°C) RESET OCCURS ABOVE CURVE 100 ...
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... GND Ground Power-Fail Input. The PFI threshold voltage is 1.70V on the MAX816 and on PFI MAX814/MAX815 parts with the T suffix 2.50V on MAX814/MAX815 parts with K, L, and N suffixes. Connect PFI to GND or V Power-Fail Output. When PFI is below its threshold, PFO is low; PFO otherwise it is high. ...
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... Figure 1a. Typical Application for Dual +3.3V and +5V Systems V CC +12V SUPPLY V CC MAX815 RESET PFI WDI WDO MANUAL MR RESET INTERRUPT PFO INPUT GND Figure 2. MAX815 Typical Application 8 _______________________________________________________________________________________ V CC +12V SUPPLY MANUAL RESET INPUT Figure 1b. MAX814 Typical Application V RT +12V SUPPLY R1 P RESET I/O LINE NMI ...
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... PFI PFO Figure 5. MAX815 Block Diagram A µP’s reset input starts the µ known state. Whenever the µ unknown state, it should be held in reset. The MAX814/MAX815/MAX816 assert reset 8 during power-up, power-down, or brownout conditions. RESET On power-up, once V CC anteed logic low of 0.4V or less stays low ...
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... Figure 7 for more information on reset ranges). The MAX816 has an adjustable reset threshold. MAX814/MAX815 K-suffix parts have a minimum reset threshold set to 4.75V, worst case. They are intended for 5.0V systems with a ±4% or better power-supply tol- erance design that must meet worst-case system para- meters over time, temperature, line, and load variations ...
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... PFO sinks at least 1.2mA to GND; other- wise it sources at least 300µA from V is the RIT is 2.50V in the MAX814/MAX815 with suffixes, or 1.70V with the T suffix also 1.70V in the MAX816. The low-line detector is a separate comparator that monitors V with a typical threshold voltage of 60mV ...
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... GND to create a manual-reset function; external debounce circuitry is not required. The watchdog circuit can be used to force a reset in the MAX815 by connecting WDO to MR driven from long cables, or the device is used in a noisy envi- ronment, connect a 0.1µF capacitor to ground to pro- vide additional noise immunity. ...
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... When the negative rail is degraded (a negative voltage of lesser magnitude), PFO is high. By adding the resis- tors and transistor as shown, a high PFO triggers reset. As long as PFO remains high, the MAX814/MAX815/ MAX816 will keep reset asserted (RESET = low, RESET = high). Note that this circuit’s accuracy depends on the PFI threshold tolerance, the V line, and the resistor ...
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... Figure 14. Interfacing to µPs with Bidirectional Reset I/O Negative-Going addition to issuing a reset to the µP during power-up, power-down, and brownout conditions, the MAX814/ MAX815/MAX816 series is relatively immune to short duration negative-going V Typical Operating Characteristics show a graph of Maximum Transient Duration vs. Reset Comparator Overdrive, for which a reset is not generated. The ...
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... Plastic DIP MAX816ESA -40°C to +85° The MAX814/MAX815 offer a choice of reset threshold voltage. From the Reset Trip Threshold table, select the suffix corre- sponding to the desired threshold and insert it into the blank to complete the part number. _____________Reset Trip Thresholds ...
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... Maxim reserves the right to change the circuitry and specifications without notice at any time. implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 16 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 16 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 16 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 © ...