ADM1087 Analog Devices, ADM1087 Datasheet
ADM1087
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ADM1087 Summary of contents
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... All four models have a dedicated enable input pin that allows the output signal to the regulator to be controlled externally. This is an active high input (ENIN) for the ADM1085 and ADM1086, and an active low input ( ENIN ) for the ADM1087 and ADM1088. The Simple Sequencers are specified over the extended − ...
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... ADM1085/ADM1086/ADM1087/ADM1088 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagrams............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 4 ESD Caution.................................................................................. 4 Pin Configuration and Function Descriptions............................. 5 Typical Performance Characteristics ............................................. 6 Circuit Information .......................................................................... 9 Timing Characteristics and Truth Tables.................................. 9 REVISION HISTORY 4/06—Rev Rev. A Added Lead-Free Models ..................................................Universal Update Outline Dimensions ...
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... Leakage Current IN CEXT Charge Current Threshold Temperature Coefficient ENIN/ENIN to ENOUT/ENOUT Propagation Delay ENIN/ENIN Voltage Low ENIN/ENIN Voltage High ENIN/ENIN Leakage Current ENOUT/ENOUT Voltage Low ENOUT/ENOUT Voltage High (ADM1086/ADM1088) ENOUT/ENOUT Open-Drain Output Leakage Current (ADM1085/ADM1087) ADM1085/ADM1086/ADM1087/ADM1088 Min Typ Max Unit 2.25 3 μ ...
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... T = 25°C, unless otherwise noted. A Table 3. Parameter CEXT ENIN, ENIN ENOUT, ENOUT (ADM1085, ADM1087) ENOUT, ENOUT (ADM1086, ADM1088) Operating Temperature Range Storage Temperature Range θ Thermal Impedance, SC70 JA Lead Temperature Soldering (10 sec) Vapor Phase (60 sec) Infrared (15 sec) ESD CAUTION ESD (electrostatic discharge) sensitive device ...
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... External Capacitor Pin. The capacitance on this pin determines the time delay on the enable output. The delay is seen only when the voltage Power Supply. CC ADM1085/ADM1086/ADM1087/ADM1088 ADM1085/ ENIN/ENIN ADM1086/ CC ADM1087/ GND CEXT 2 5 ADM1088 V ENOUT/ENOUT 3 TOP VIEW 4 IN (Not to Scale) Figure 2. Pin Configuration ...
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... ADM1085/ADM1086/ADM1087/ADM1088 TYPICAL PERFORMANCE CHARACTERISTICS 700 680 660 640 V RISING TRIP 620 600 580 560 V FALLING TRIP 540 520 500 –40 –25 – TEMPERATURE (°C) Figure 3. V Threshold vs. Temperature IN 12.0 11.5 11.0 10.5 10 –40°C A 9.5 9.0 8.5 8.0 2.1 2.4 2.7 3.0 V (V) CC Figure 4. Supply Current vs. Supply Voltage 20 18 ...
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... Falling Propagation Delay vs. Temperature CC 500 450 400 350 300 250 200 150 100 50 0 2.1 2.4 2.7 3.0 SUPPLY VOLTAGE (V) Figure 11. Output Fall Time vs. Supply Voltage ADM1085/ADM1086/ADM1087/ADM1088 200 180 160 140 120 100 3.3 3.6 0 Figure 12. ENIN/ ENIN Leakage Current vs. ENIN/ ENIN Voltage 200 180 160 ...
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... ADM1085/ADM1086/ADM1087/ADM1088 300 280 260 240 220 200 180 160 140 120 100 –40 –25 – TEMPERATURE (°C) Figure 15. CEXT Charge Current vs. Temperature 100 –40 –25 – TEMPERATURE (°C) to ENOUT/ ENOUT Propagation Delay (CEXT Floating) vs. ...
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... CIRCUIT INFORMATION TIMING CHARACTERISTICS AND TRUTH TABLES The enable outputs of the ADM1085/ADM1086/ADM1087/ ADM1088 are related to the V and enable inputs by a simple IN AND function. The enable output is asserted only if the enable input is asserted and the voltage above V IN the time delay elapsed. Table 5 and Table 6 show the enable ...
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... ADM1085/ADM1086/ADM1087/ADM1088 OPEN-DRAIN AND PUSH-PULL OUTPUTS The ADM1085 and ADM1087 have open-drain output stages that require an external pull-up resistor to provide a logic high voltage level. The geometry of the NMOS transistor enables the output to be pulled up to voltage levels as high (≤22V) CC ADM1085/ADM1087 Figure 21 ...
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... Figure 23 to Figure 25 illustrate how each of the ADM1085/ADM1086/ ADM1087/ADM1088 simple sequencers can be used in multiple-supply systems, depending on which regulators are used and which output stage is preferred. 12V ...
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... ENIN CEXT ENABLE CONTROL 12V 3.3V 2.5V 1.8V 1.2V 12V IN SD OUT ADP3334 3.3V 3. ENOUT IN ADM1087 ENIN CEXT Figure 25. Typical ADM1087 Application Circuit Using ADP3334 Voltage Regulators IN EN OUT EN DC/DC 2.5V 3. ENOUT IN ADM1086 ENIN CEXT EN1 EN2 EN3 Figure 24. Typical ADM1086 Application Circuit 12V ...
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... MICROPROCESSOR POWER 0V 5V DISPLAY POWER 0V Figure 27. Dual LOFO Power-Supply Sequencing ADM1085/ADM1086/ADM1087/ADM1088 SIMULTANEOUS ENABLING The enable output can drive multiple enable or shutdown regulator inputs simultaneously. 12V CONTROL POWER GOOD SIGNAL DELAYS Sometimes sequencing is performed by asserting power good signals when the voltage regulators are already on, rather than sequencing the power supplies directly ...
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... ENIN Figure 30. Quad-Supply Power Good Indicator SEQUENCING WITH FET SWITCHES The open-drain outputs of the ADM1085 and ADM1087 can drive external FET transistors that can switch on power supply rails. All that is needed is a pull-up resistor to a voltage source that is high enough to turn on the FET. ...
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... Thin Shrink Small Outline Transistor Package (SC70) 3k 6-Lead Thin Shrink Small Outline Transistor Package (SC70) Evaluation Board for the ADM1087 device. This board can also be used to evaluate the other devices in the family. Sample can be ordered separately. Rev Page 0.46 0.36 0.22 ...
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... ADM1085/ADM1086/ADM1087/ADM1088 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04591-0-4/06(A) T Rev Page ...