ADM8690 Analog Devices, ADM8690 Datasheet
ADM8690
Specifications of ADM8690
Related parts for ADM8690
ADM8690 Summary of contents
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... One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 Fax: 781.461.3113 Microprocessor Supervisory Circuits RESET 1 4.65V 2 GENERATOR WATCHDOG TRANSITION DETECTOR ADM8690 (1.6sec) 1.3V Figure 1. ADM8690 BATT ON ADM8691/ ADM8695 V CE LOW LINE 1 4.65V RESET RESET AND RESET WATCHDOG RESET GENERATOR TIME BASE WATCHDOG ...
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... Using a Rechargeable Battery for Backup ............................... 15 Adding Hysteresis to the Power-Fail Comparator ................. 15 Monitoring the Status of the Battery ....................................... 15 Alternate Watchdog Input Drive Circuits ............................... 16 Typical Applications ....................................................................... 17 ADM8690 Applications ............................................................. 17 ADM8691/ADM8695 Applications ......................................... 17 RESET Output ............................................................................ 18 Power-Fail Detector ................................................................... 18 RAM Write Protection............................................................... 18 ...
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... To place an order, see the Ordering Guide. Nominal Watchdog Battery Backup CC Timeout Period Switching 1.6 sec Yes 100 ms, 1.6 sec, ADJ Yes 100 ms, 1.6 sec, ADJ Yes Rev Page ADM8690/ADM8691/ADM8695 are fabricated using an Base Drive, Chip Enable Ext PNP Signals No No Yes Yes Yes Yes as ...
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... Battery Switchover Hysteresis BATT ON Output Voltage BATT ON Output Short-Circuit Current RESET AND WATCHDOG TIMER Reset Voltage Threshold Reset Threshold Hysteresis Reset Timeout Delay ADM8690 and ADM8691 ADM8695 Watchdog Timeout Period, Internal Oscillator Watchdog Timeout Period, External Clock Minimum WDI Input Pulse Width ...
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... WDI is a three-level input that is internally biased to 38 Min Typ Max 0.8 3.0 3 0.4 V − 1.5 OUT V − 0.05 OUT 3 7 ± 500 4 and has an input impedance of approximately 5 MΩ. CC Rev Page ADM8690/ADM8691/ADM8695 Unit Test Conditions/Comments μ 3.2 mA SINK 3.0 mA SOURCE μ SOURCE CC ns μ ...
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... ADM8690/ADM8691/ADM8695 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter BATT All Other Inputs Input Current BATT GND Digital Output Current Power Dissipation, 8-Lead PDIP θ Thermal Impedance JA Power Dissipation, 8-Lead SOIC θ Thermal Impedance JA Power Dissipation, 16-Lead PDIP θ ...
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... Logic Output. The watchdog output, WDO, goes low if WDI remains either high or low for longer than the watchdog timeout period. WDO is set high by the next transition at WDI. If WDI is unconnected or at midsupply, the watchdog timer is disabled and WDO remains high. WDO also goes high when LOW LINE goes low. Rev Page ADM8690/ADM8691/ADM8695 RESET ...
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... CC serviced within its timeout period. The reset threshold is typically 4.65 V. RESET remains low for ADM8690 ADM8691 / ) or 200 ms ( also goes low for ADM8690 ADM8691 / enabled but not serviced within its timeout period. The the ADM8691 ADM8695 / , as shown in Table 5 can either connect to an open-collector reset bus or directly drive a CMOS gate without an external pull-up resistor ...
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... ADM8690/ADM8691/ADM8695 –60 – TEMPERATURE (°C) Figure 8. PFI Input Threshold vs. Temperature TEMPERATURE (°C) Figure 9. Reset Active Time vs. Temperature 4. 4.67 4.65 4.63 4.61 4.59 4.57 4.55 –60 – TEMPERATURE (°C) Figure 10. Reset Voltage Threshold vs. Temperature 90 120 ADM8690/ ADM8691 100 120 90 120 ...
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... ADM8690/ADM8691/ADM8695 6 PFO PFI PFO 2 1. PFI 1.35 1.25 0 0.1 0.2 0.3 0.4 0.5 TIME (µs) Figure 11. Power-Fail Comparator Response Time, Falling 25° PFI PFO 1 1.3V PFO 0 1.35 PFI 1. TIME (µs) Figure 12. Power-Fail Comparator Response Time, Rising 25°C A 30pF 1 ...
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... CC In addition to RESET , the active high RESET output. This output is the complement of RESET and is intended for processors that require an active high reset signal. BATT Rev Page ADM8690/ADM8691/ADM8695 should be connected to V OUT invalid level. When ...
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... If this line is not toggled within the selected timeout period, a RESET pulse is generated. The nominal watchdog timeout period is preset at 1.6 sec on the ADM8690. The ADM8691/ADM8695 a fixed timeout period—short (100 ms) or long (1.6 sec)—or for an adjustable timeout period. Some systems are unable to service the watchdog timer immediately after a reset ...
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... V invalid level. Similar protection of EEPROMs can be achieved using the CE V RESET LOW LINE CE CE OUT Rev Page ADM8690/ADM8691/ADM8695 / ) include memory protection circuitry invalid level. Two additional pins CC and CE ) can be used to control the chip enable or write OUT is present with propagation delay ...
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... ADM8690/ADM8691/ADM8695 POWER-FAIL WARNING COMPARATOR An additional comparator is provided for early warning of failure in the microprocessor power supply. The power-fail input (PFI) is compared to an internal 1.3 V reference. The power-fail output ( PFO ) goes low when the voltage at PFI is less than 1.3 V. Typically, PFI is driven by an external voltage divider that senses either the unregulated dc input to the system 5 V regulator or the regulated 5 V output ...
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... This is done under processor control using CE 0.1µF high during the battery backup mode, the test load is not applied V OUT to the battery while use, even if the microprocessor is not powered. BATTERY OPTIONAL TEST LOAD Rev Page ADM8690/ADM8691/ADM8695 5V 7805 1.3V PFO PFI ...
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... A 0.01 μF capacitor sets a watchdog timeout delay of 100 sec. When the control input is low, the OSC SEL pin is driven high, selecting the internal oscillator. The 100 ms or the 1.6 sec ADM8690/ ADM8691/ period is chosen, depending on which diode is used, as shown ADM8695 in Figure 29. With D1 inserted, the internal timeout is set to 100 ms ...
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... power failure occurs decays and V is switched thereby maintaining OUT BATT power for the CMOS RAM. A RESET pulse is also generated falls below 4.65 V for the ADM8690. RESET remains when V CC low for 50 ms after V returns ...
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... ADM8690/ADM8691/ADM8695 RESET OUTPUT The internal voltage detector monitors V RESET output to hold the microprocessor reset line low when is below 4. internal timer holds RESET low for (200 ms for the ADM8695) after V This prevents repeated toggling of RESET , even if the 5 V power drops out and recovers with each power line cycle. ...
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... PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. Figure 34. 8-Lead Standard Small Outline Package [SOIC_N] Narrow Body (R-8) Dimensions shown in millimeters and (inches) Rev Page ADM8690/ADM8691/ADM8695 0.325 (8.26) 0.310 (7.87) 0.300 (7.62) 0.195 (4.95) 0.130 (3.30) 0.115 (2.92) 0.014 (0.36) ...
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... ADM8690/ADM8691/ADM8695 0.210 (5.33) MAX 0.150 (3.81) 0.130 (3.30) 0.115 (2.92) 0.022 (0.56) 0.018 (0.46) 0.014 (0.36) 0.30 (0.0118) 0.10 (0.0039) COPLANARITY 0.10 0.800 (20.32) 0.790 (20.07) 0.780 (19.81 0.280 (7.11) 0.250 (6.35) 1 0.240 (6.10) 8 0.100 (2.54) BSC 0.060 (1.52) MAX 0.015 (0.38) 0.015 (0.38) MIN GAUGE PLANE SEATING PLANE 0.005 (0.13) MIN 0.070 (1.78) 0.060 (1.52) 0.045 (1.14) COMPLIANT TO JEDEC STANDARDS MS-001-AB CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN ...
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... Dimensions shown in millimeters and (inches) 5.10 5.00 4. 4.50 6.40 4.40 BSC 4. PIN 1 1.20 MAX 0.20 0.09 0.30 0.65 0.19 SEATING BSC PLANE COPLANARITY 0.10 COMPLIANT TO JEDEC STANDARDS MO-153-AB Figure 38. 16-Lead Thin Shrink Small Outline Package [TSSOP] (RU-16) Dimensions shown in millimeters Rev Page ADM8690/ADM8691/ADM8695 0.50 (0.0197) 45° 0.25 (0.0098) 8° 0° 1.27 (0.0500) 0.40 (0.0157) 0.75 8° 0.60 0° 0.45 ...
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... Model Temperature Range ADM8690AN −40°C to +85°C ADM8690ANZ −40°C to +85°C ADM8690ARN −40°C to +85°C ADM8690ARN-REEL −40°C to +85°C ADM8690ARNZ −40°C to +85°C ADM8691ANZ −40°C to +85°C ADM8691ARN −40°C to +85°C ADM8691ARN-REEL −40°C to +85°C ADM8691ARNZ − ...
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... Data Sheet NOTES ADM8690/ADM8691/ADM8695 Rev Page ...
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... ADM8690/ADM8691/ADM8695 NOTES ©2006–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D00093-0-12/11(C) Rev Page Data Sheet ...