DS1708 Dallas Semiconductor, DS1708 Datasheet
DS1708
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DS1708 Summary of contents
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... DIP and 8–pin SOIC packages 8–pin DIP, 8–pin SOIC and 8–pin –SOP packages available Industrial temperature range – +85 C DESCRIPTION The DS1707/DS1708 3.3 or 5.0 Volt MicroMonitor moni- tors three vital conditions for a microprocessor: power supply, voltage sense, and external override. A preci- sion temperature–compensated ...
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... DC voltage level closer to the main system power input. Since the IN trip point V ues for R1 and R2 can be determined by the equation as shown in Figure 5. DS1707/DS1708 requires that the voltage at the IN pin be limited to V voltage at the supply being monitored (V falls below be derived as shown in Figure 5. A simple approach to ...
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... PUSHBUTTON RESET CONTROLLED BY NMI Figure 3 UPSTREAM SUPPLY VOLTAGE DIGITAL SAMPLER DIGITAL SAMPLER LEVEL SENSE AND DEBOUNCE PBRST V CC DS1708 GND IN PBRST DS1707 GND IN DIGITAL DELAY RST RST RST 8051 NC NMI INT0 RST RST RST NC NMI DS1707/DS1708 NMI RST RST P P 010996 3/9 ...
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... NON–MASKABLE INTERRUPT CIRCUIT EXAMPLE Figure 5 V SENSE SENSE Example: V SENSE V = 3.3 volts CC 10K = R2 4.70 Therefore: x 3.3 1.25 R1 4.5 010996 4/9 t PDLY PBRST RST V RST CC DS1708 GND NC NMI 1.25 V MAX R2 = 4.70 volts at the trip point 12.4 volts maximum 10K x 1.25 R1 10K RST SENSE 27.6K ...
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... TIMING DIAGRAM: NON–MASKABLE INTERRUPT Figure 6 V > 1.25V IN V TP(MAX) NMI TIMING DIAGRAM: POWER DOWN Figure RST RST TP(MIN) t IPD CCTP(MAX) V CCTP V CCTP(MIN) t RPD TP(MAX TP(MIN) t IPD V OH RST SLEWS WITH V CC DS1707/DS1708 010996 5/9 ...
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... DS1707/DS1708 TIMING DIAGRAM: POWER UP Figure 010996 6 CCTP(MAX) V CCTP V CCTP(MIN) t RPU RST RST RST RST ...
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... PARAMETER V Trip Point DS1707 CC V Trip Point DS1708 CC V Trip Point DS1708T CC V Trip Point DS1708S CC V Trip Point DS1708R CC Input Leakage Output Current @ 2.4 volts Output Current @ 0.4 volts Output Voltage Operating Current @ V < 5.5 volts CC Operating Current @ V < 3.6 volts CC IN Input Trip Point ...
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... DS1707/DS1708 AC ELECTRICAL CHARACTERISTICS PARAMETER PBRST = V IL Reset Active Time V Detect to RST and RST CC V Slew Rate CC V Detect to RST and RST CC V Slew Rate CC PBRST Stable Low to RST and RST VIN Detect to NMI NOTES: 1. All voltages are referenced to ground. 2. PBRST is internally pulled ...
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... and D represents the device type and tolerance. ABCD 707_ – DS1707 708_ – DS1708 708R – DS1708R 708S – DS1708S 708T – DS1708T WWY represents the device manufacturing Work Week, and Year ABCD WWY (118 MIL) DS1707/DS1708 010996 9/9 ...