ADM691 Analog Devices, ADM691 Datasheet
ADM691
Specifications of ADM691
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ADM691 Summary of contents
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... A 1.3 V threshold detector for power fail warning, low battery detection monitor a power supply other than +5 V. The ADM691, ADM693 and ADM695 are available in 16-pin DIP and small outline packages and provide three additional functions. 1. Write protection of CMOS RAM or EEPROM. ...
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... RESET AND WATCHDOG TIMER Reset Voltage Threshold ADM690, ADM691, ADM694, ADM695 ADM692, ADM693 Reset Threshold Hysteresis Reset Timeout Delay ADM690, ADM691, ADM692, ADM693 ADM694, ADM695 Watchdog Timeout Period, Internal Oscillator Watchdog Timeout Period, External Clock Minimum WDI Input Pulse Width RESET Output Voltage @ V ...
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... A 0 250 kHz 4 kHz and has an input impedance of approximately 125 Model ADM690AN + 0.5 V ADM690AQ OUT ADM690SQ ADM691AN ADM691AR ADM691AQ ADM691SQ ADM692AN ADM692AQ ADM692SQ ADM693AN ADM693AR ADM693AQ ADM693SQ ADM694AN ADM694AQ ADM694SQ ADM695AN ADM695AR ADM695AQ ADM695SQ –3– ADM690–ADM695 Test Conditions/Comments OSC SEL = 0 V ...
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... Table I and Figure 4). With OSC SEL high or floating, the internal oscillator is enabled and the reset active time is fixed typ. (ADM691/ADM693) or 200 ms typ (ADM695). In this mode the OSC IN pin selects between fast (100 ms) and slow (1.6 s) watchdog timeout periods. In both modes, the timeout period immediately after a reset is 1 ...
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... If the continuous output current requirement at V 100 lower V to the V an external PNP pass transistor may be connected in parallel CC BATT with the internal transistor. The BATT ON output (ADM691 falls, and ADM693/ADM695) can directly drive the base of the external BATT rises ...
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... V as low This ensures that the CC microprocessor is held in a stable shutdown condition. This RESET active time is adjustable on the ADM691/ADM693/ ADM695 by using an external oscillator or by connecting an external capacitor to the OSC IN pin. Refer to Table I and Figure 4. The guaranteed minimum and maximum thresholds of the ADM690/ADM691/ADM694/ADM695 are 4 ...
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... The watchdog timeout period is fixed at 1.6 seconds, and the reset pulse width is fixed the ADM690/ADM692. On the ADM694 the watchdog timeout period is also 1.6 sec- onds but the reset pulse width is fixed at 200 ms. The ADM691/ ADM693/ADM695 allow these times to be adjusted as shown in Table I. Figure 4 shows the various oscillator configurations which can be used to adjust the reset pulse width and watchdog timeout period ...
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... ADM690–ADM695 CE Gating and RAM Write Protection (ADM691/ADM693/ ADM695) The ADM691/ADM693/ADM695 products include memory protection circuitry which ensures the integrity of data in mem- ory by preventing write operations when V level. There are two additional pins, CE may be used to control the Chip Enable or Write inputs of CMOS RAM ...
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... TIME – s Figure 15. Power Fail Comparator Response Time –9– A4 3.36 V 100 500ms Figure 10. Reset Output Voltage vs. Supply Voltage 4. +5V CC 4.68 POWER-UP ADM690 ADM691 4.66 ADM694 ADM695 4.64 POWER-DOWN 4. 100 120 TEMPERATURE – C Figure 13. Reset Voltage Threshold vs. Temperature ...
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... If the continuous output current requirements at V 100 lower V –V voltage differential is desired, CC OUT an external PNP pass transistor may be connected in parallel with the internal transistor. The BATT ON output (ADM691/ ADM693/ADM695) can directly drive the base of the external transistor. PNP TRANSISTOR +5V INPUT 0.1 F ...
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INPUT POWER BATT 10M BATTERY ADM69x PFI 10M 20k OPTIONAL CE OUT TEST LOAD Figure 20. Monitoring the Battery Status Alternate Watchdog Input Drive Circuits The watchdog feature can be enabled and disabled under pro- gram ...
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... POWER V > 8V returns CC BATTERY Figure 23b. ADM690/ADM692/ADM694 Typical Application Circuit B ADM691, ADM693, ADM695 A typical connection for the ADM691/ADM693/ADM695 is shown in Figure 24. CMOS RAM is powered from power is present this is routed routed to V BATT V , but if more current is required, an external PNP transistor CC can be added ...
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... If a hardware or soft- RESET 0.1 F ware failure occurs such that WDI not toggled, the ADM691/ ADM693 will issue (200 ms for ADM695) RESET pulse after 1.6 seconds. This typically restarts the micro- processor’s power-up routine. A new RESET pulse is issued every 1 ...
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ADM690–ADM695 0.210 (5.33) 0.200 (5.05) 0.125 (3.18) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 8-Pin Plastic DIP (N- 0.280 (7.11) PIN 1 0.240 (6.10 0.325 (8.25) 0.430 (10.92) 0.300 (7.62) 0.348 (8.84) 0.060 (1.52) 0.210 ...
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SEATING 0.299 (7.60) REV. A 16-Lead Cerdip (Q-16 0.310 (7.87) PIN 1 0.220 (5.59 0.840 (21.34) MAX 0.060 (1.52) 0.015 (0.38) 0.200 (5.08) MAX 0.150 (3.81) MIN PLANE 0.022 (0.558) 0.100 (2.54) 0.070 (1.78) BSC 0.014 ...
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