ADM8691 Analog Devices, ADM8691 Datasheet
ADM8691
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ADM8691 Summary of contents
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... LOW LINE 1 4.65V RESET RESET AND RESET WATCHDOG RESET GENERATOR TIME BASE WATCHDOG WATCHDOG WATCHDOG TRANSITION DETECTOR TIMER OUTPUT (WDO) POWER-FAIL OUTPUT (PFO) 1.3V Figure 2. ADM8691/ADM8695 www.analog.com ©2006–2011 Analog Devices, Inc. All rights reserved. V OUT RESET POWER-FAIL OUTPUT (PFO) OUT OUT ...
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... Pin Configurations and Function Descriptions ........................... 7 Typical Performance Characteristics ............................................. 9 Circuit Information ........................................................................ 11 Battery Switchover Section ........................................................ 11 Power-Fail RESET Output ......................................................... 11 Watchdog Timer RESET ............................................................ 12 Watchdog Output ( WDO ) (ADM8691/ADM8695) ................. 13 CE Gating and RAM Write Protection (ADM8691/ADM8695) ............................................................. 13 REVISION HISTORY 12/11—Rev Rev. C Deleted ADM8692 and ADM8693 ............................. Throughout Changes to Table 4 ............................................................................ 7 Change to Power-Fail RESET Output Section ...
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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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... 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 RESET Output Voltage ...
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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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... Table 5 and Figure 17 through Figure 20). When OSC SEL is high or floating, the internal oscillator is enabled and the reset active time is fixed typical (ADM8691) or 200 ms typical (ADM8695). In this mode, the OSC IN pin selects either the fast (100 ms) or slow (1.6 sec) watchdog timeout period. In both modes, the timeout period immediately after a reset is 1 ...
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... 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. Logic Output. RESET is an active high output the inverse of RESET. ...
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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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... V voltage differential is desired, CC OUT an external PNP pass transistor can be connected in parallel with the internal transistor. The BATT ON output (ADM8691/ ADM8695) can directly drive the base of the external transistor (see Figure 24 Ω MOSFET switch connects the V BATT battery backup. This MOSFET has very low input-to-output ...
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... On the ADM8690 the watchdog timeout period is fixed at 1.6 sec, and the reset pulse width is fixed at 50 ms. The ADM8691/ ADM8695 allow these times to be adjusted, as shown in Table 5. Figure 17, Figure 18, Figure 19, and Figure 20 show the various oscillator configurations that can be used to adjust the reset pulse width and watchdog timeout period ...
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... OSC SEL NC ADM8691/ ADM8695 7 OSC IN Figure 20. Internal Oscillator (100 ms Watchdog GATING AND RAM WRITE PROTECTION ( ADM8691 ADM8695 ADM8691 ADM8695 / ) The ADM8691/ADM8695 that ensures the integrity of data in memory by preventing write operations when V goes inputs of CMOS RAM. When V replica of CE below the reset voltage threshold or V ...
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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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... If the continuous output current requirements at V 100 mA lower V − V voltage differential is desired, CC OUT an external PNP pass transistor can be connected in parallel with the internal transistor. The BATT ON output (ADM8691/ ADM8695) can directly drive the base of the external transistor. PNP TRANSISTOR 5V INPUT POWER 0.1µF V ...
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... In most cases, a better method is to extend the watchdog period rather than disable the watchdog. For the ADM8691/ADM8695, the watchdog period can be extended under program control using the circuit shown in Figure 29. When the control input is high, the OSC SEL pin is low and the watchdog timeout is set by the external capacitor. A 0.01 μ ...
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... INPUT POWER V > 8V POWER BATTERY MICROPROCESSOR SYSTEM ADM8691/ADM8695 Figure 32 shows a typical connection for the ADM8691/ADM8695. CMOS RAM is powered from V this voltage is routed can supply up to 100 mA from V OUT required, an external PNP transistor can be added. When V higher than base drive for the external transistor. A 0.1 μF capac- itor is connected to V CMOS RAM ...
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... OSC IN external clock can be used (see Table 5 and Figure 17 through Figure 20). The manual reset switch and the 0.1 μF capacitor connected to the reset line can be omitted if a manual reset is not needed. An inverted, active high RESET output is also available on the ADM8691/ ADM8695. POWER-FAIL DETECTOR The ...
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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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... ADM8691ARN-REEL −40°C to +85°C ADM8691ARNZ −40°C to +85°C ADM8691ARW −40°C to +85°C ADM8691ARW-REEL −40°C to +85°C ADM8691ARWZ −40°C to +85°C ADM8691ARU −40°C to +85°C ADM8691ARU-REEL −40°C to +85°C ADM8691ARUZ −40°C to +85°C ADM8695ARW − ...
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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 ...