MAX814KCPA Maxim Integrated, MAX814KCPA Datasheet
MAX814KCPA
Specifications of MAX814KCPA
Related parts for MAX814KCPA
MAX814KCPA Summary of contents
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... CC MAX814 GND 3 PFI 4 DIP/SO ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. µP Supervisory Circuits ____________________________Features ♦ ±1% Worst-Case Reset Threshold Accuracy ♦ 4.8V, 4.7V, 4.55V, 3.03V, or Adjustable Reset Thresholds ♦ ...
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... Accuracy, Low-Power, +3V and +5V µP Supervisory Circuits ABSOLUTE MAXIMUM RATINGS Terminal Voltage (with respect GND) V ....................................................................-0.3V to +6.0V CC All Other Pins (Note 1)........................... -0. Terminal Current (PFI, RESET IN, MR)................................10mA Terminal Current (all other pins) .........................................20mA Continuous Power Dissipation (T = +25°C) A Plastic DIP (derate 9.09mW/°C above +70°C) ............727mW SO (derate 5.88mW/° ...
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... Reset Threshold Hysteresis Reset Pulse Width V V RESET Output Voltage RESET, WDO, PFO, LOW LINE Output Voltage V V Watchdog Timeout Period t _______________________________________________________________________________________ µP Supervisory Circuits = 4.75V to 5.5V for MAX814L/MAX815L CONDITIONS Low High MRHI (Note 5.0V PFI CC PFI ...
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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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... TEMPERATURE (°C) LOW-LINE TO RESET THRESHOLD vs. TEMPERATURE (V RISING -60 -40 - TEMPERATURE (°C) _______________________________________________________________________________________ µP Supervisory Circuits V SUPPLY CURRENT vs. TEMPERATURE CC 5V PARTS (MAX814/MAX815K 5. 3. 100 -60 -40 - TEMPERATURE (° ...
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... Accuracy, Low-Power, +3V and +5V µP Supervisory Circuits ____________________________Typical Operating Characteristics (continued +25°C, unless otherwise noted.) A RESET THRESHOLD DEVIATION vs. TEMPERATURE 3V PARTS (MAX814T/MAX815T, MAX816 -60 -40 - TEMPERATURE (°C) RESET THRESHOLD DEVIATION vs. TEMPERATURE 3V PARTS (MAX814T/MAX815T, MAX816 -60 -40 -20 ...
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... Threshold Voltage is determined by part number suffix 4.80V 4.70V 4.55V 3.03V. _______________Detailed Description The MAX814/MAX815/MAX816 are high-accuracy, low- power microprocessor (µP) supervisory circuits. They have µP-reset, watchdog-timer, and power-fail func- tions. Typical applications illustrating their similarities and differences are shown in Figures 1, 2, and 3. ...
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... Accuracy, Low-Power, +3V and +5V µP Supervisory Circuits +3.3V + MAX814K/L/N PFI RESET MR RESET PFO GND 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 PFO INPUT GND Figure 2. MAX815 Typical Application 8 _______________________________________________________________________________________ +12V SUPPLY ...
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... GND Figure 4. MAX814 Block Diagram MAX816 150µA 1 RESET MR GENERATOR 6 RESET IN 1.70V 4 PFI 1.70V GND 3 Figure 6. MAX816 Block Diagram _______________________________________________________________________________________ µP Supervisory Circuits 8 RESET WATCHDOG 6 TRANSITION WDI DETECTOR 7 RESET 150µ LOW LINE RESET THRESHOLD 4 5 PFI PFO Figure 5 ...
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... Accuracy, Low-Power, +3V and +5V µP Supervisory Circuits Reset Threshold The MAX814/MAX815 have fixed, factory-set reset thresholds, signified by the first suffix letter in the part number (see 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 ± ...
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... NMI interrupt. Connecting WDO to MR enables the watchdog timeout to generate a reset in the MAX815. ______________________________________________________________________________________ µP Supervisory Circuits Critical systems often require early warning to indicate when power is failing. This warning provides time for the µP to store vital data and take care of any additional “ ...
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... Accuracy, Low-Power, +3V and +5V µP Supervisory Circuits WDI WDO RESET RESET 0V Figure 8. MAX815 Watchdog Timing where C is the capacitance (in Farads), I HOLD the current being drained from the capacitor (in Amperes), and V is the low-line to reset threshold dif- LR ference (in Volts) ...
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... 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. CC ______________________________________________________________________________________ µP Supervisory Circuits 340kΩ 100kΩ R1 Figure 11. Monitoring Both +5V and +12V CC by connecting a ...
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... Accuracy, Low-Power, +3V and +5V µP Supervisory Circuits + MAX814 MAX815 PFO PFI MAX816 R2 RESET GND V- + +5V PFO TRIP 5 - 2.5 2 TRIP , = V < 0V TRIP 2.5V (K, L, N); 1.70V (T AND MAX816) PFT Figure 12. Monitoring a Negative Voltage BEGIN PROGRAM SET LOW WDI ...
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... RESET TRIP THRESHOLD SUFFIX MIN (V) K 4.75 L 4.65 N 4.50 T 3.00 — MAX816 — Adjustable ______________________________________________________________________________________ µP Supervisory Circuits ___________________Chip Information TRANSISTOR COUNT: 744 PIN-PACKAGE 8 Plastic DIP Plastic DIP Pages changed at Rev 1: 1–4, 12-16 Plastic DIP Plastic DIP Plastic DIP Plastic DIP ...
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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. 16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products ...