DS1236AN Maxim Integrated, DS1236AN Datasheet
DS1236AN
Specifications of DS1236AN
Related parts for DS1236AN
DS1236AN Summary of contents
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FEATURES Holds microprocessor in check during power transients Halts and restarts an out-of-control microprocessor Monitors pushbutton for external override Warns microprocessor of an impending power failure Converts CMOS SRAM into nonvolatile memory Unconditionally write protects memory when power supply ...
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An internal watchdog timer can also force the reset outputs to the active state if the strobe input is not driven low prior to watchdog timeout. Reset control and wake-up/sleep control inputs ...
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POWER MONITOR The DS1236A employs a band gap voltage reference and a precision comparator to monitor the 5-volt supply ( microprocessor-based systems. When an out-of-tolerance condition occurs, the RST and CC outputs are driven to the active state. ...
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NON-MASKABLE INTERRUPT The DS1236A generates a non-maskable interrupt microprocessor. A precision comparator monitors the voltage level at the IN pin relative to a reference generated by the internal band gap. The IN pin is a high-impedance input allowing for a ...
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DS1236A FUNCTIONAL BLOCK DIAGRAM Figure DS1236A ...
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If the IN pin is connected to V CCO mode (RC=0). In the CMOS mode (RC=V produce a pulse on the pin. Given that any NMI the pin will remain high. The NMI CCTP V . Once ...
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ST/INPUT TIMING Figure 2 NMI/FROM ST/INPUT Figure DS1236A ...
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POWER MONITOR, WATCHDOG Figure 4 PUSHBUTTON RESET TIMING Figure DS1236A ...
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NON-MASKABLE INTERRUPT Figure 6 EXAMPLE 1: 5-VOLT SUPPLY 10k OHM, V ∴ 4.80 = EXAMPLE 2: 12-VOLT SUPPLY 10k OHM, V ∴ 9.00 = NONVOLATILE SRAM Figure 10k X 2.54 10k R1 + ...
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When the RC pin is tied to ground, the DS1236A is designed to interface with NMOS processors which do not have the microamp currents required during a battery backed mode. Grounding the RC pin does, however, continue to support nonvolatile ...
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In addition, as long as the IN pin is less than V NMI additional pulses. In this way, the NMI the supply voltage, as monitored by the IN pin, is above or below a selected operating value. This ...
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If the RC pin is tied high, the RST and power-down in a sleep mode. Removal of the sleep mode by the pin threshold at V when the RC pin is tied high (CMOS mode). Subsequent power-up ...
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CMOS MODE POWER-DOWN ( Figure 9 CCO DS1236A ...
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NMOS MODE POWER-DOWN (RC = GND) Figure DS1236A ...
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NMOS MODE POWER-UP (RC = GND) Figure DS1236A ...
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CMOS MODE POWER-UP ( Figure 12 CCO DS1236A ...
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WAKE/SLEEP CONTROL Figure 13 OPTIONS FOR INVOKING WAKEUP Figure DS1236A ...
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ABSOLUTE MAXIMUM RATINGS* Voltage on V Pin Relative to Ground CC Voltage on I/O Relative to Ground Operating Temperature Operating Temperature (Industrial Version) Storage Temperature Soldering Temperature * This is a stress rating only and functional operation of the device ...
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PARAMETER Power Sup. Trip Point Power Supply Trip (5% Option) IN Input Pin Current IN Input Trip Point AC ELECTRICAL CHARACTERISTICS PARAMETER V Fail Detect to RST, RST NMI TP RESET Active Time Pulse Width NMI Pulse ...
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NOTES: 1. All voltages referenced to ground. A 0.1 μF capacitor is recommended between V 2. Measured with PF, CEO CCO 25° the maximum average load which the DS1236A can supply at V CCO1 ...