ADP1864 Analog Devices, ADP1864 Datasheet
ADP1864
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ADP1864 Summary of contents
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... The ADP1864 provides system flexibility by allowing accurate setting of the current limit with an external resistor, and the output voltage is easily adjustable using two external resistors. The ADP1864 includes an internal soft start to allow quick power-up while preventing input inrush current. Additional safety features include short-circuit protection, output overvoltage protection, and input undervoltage protection ...
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... ADP1864 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Typical Applications Diagram ........................................................ 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Absolute Maximum Ratings ............................................................ 4 ESD Caution .................................................................................. 4 Pin Configuration and Function Descriptions ............................. 5 Typical Performance Characteristics ............................................. 6 Theory of Operation ........................................................................ 8 Loop Startup .................................................................................. 8 Short-Circuit Protection .............................................................. 9 Undervoltage Lockout (UVLO) ................................................. 9 Overvoltage Lockout Protection (OVP).................................... 9 REVISION HISTORY 4/08— ...
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... GATE PGATE minimum low duration Figure 1 . Line regulation is specified as the change in the FB voltage resulting from change in Figure 1 . Load regulation is specified as the change in the FB voltage resulting from change in the Rev Page ADP1864 Min Typ Max Unit 3. 235 360 μ ...
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... ADP1864 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter IN to GND CS, PGATE to GND FB, COMP to GND θ 2-Layer (SEMI Standard Board) JA θ 4-Layer (JEDEC Standard Board) JA Operating Junction Temperature Range Storage Temperature Range Lead Temperature Rework Temperature (J-STD-020B) Peak Reflow Temperature, (20 sec to 40 sec, J-STD-020B) Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device ...
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... IN Power Input the power supply to the ADP1864 and the positive input of the current sense amplifier. Connect IN to the positive side of the input voltage source. Bypass IN to PGND with a 10 μF or larger capacitor as close as possible to the ADP1864. For additional high frequency noise reduction, add a 0.1 μF capacitor to PGND at the IN pin. ...
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... ADP1864 TYPICAL PERFORMANCE CHARACTERISTICS 0.810 0.805 0.800 0.795 0.790 –40 – TEMPERATURE (°C) Figure 3. Reference Voltage vs. Temperature 600 590 580 570 560 550 –40 – TEMPERATURE (°C) Figure 4. Normalized Oscillator Frequency vs. Temperature 3.10 3.05 3.00 UVLO RISING 2.95 2.90 UVLO FALLING 2 ...
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... Figure 10. Quiescent Current vs. Temperature 650 640 630 620 610 600 590 580 570 560 550 540 530 520 = 3.15V 510 500 100 120 3 Figure 11. Oscillator Frequency vs. Input Voltage 100 120 Rev Page ADP1864 TEMPERATURE = 25° ( ...
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... FET provides the additional current required by the load. LOOP STARTUP Pulling the COMP pin to GND disables the ADP1864. When the COMP pin is released from GND, an internal 0.6 μA current source charges the external compensation capacitor on the COMP node. Once the COMP voltage has charged to 0.67 V, the internal control blocks are enabled and COMP is pulled up to its minimum normal operating voltage (0 ...
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... FB decreases to 0. which time the ADP1864 resumes normal operation. SOFT START The ADP1864 includes a soft start feature that limits the rate of increase in the inductor current once the part is enabled. Soft start is activated when the input voltage is increased above the UVLO threshold or COMP is released from GND ...
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... ADP1864 APPLICATIONS INFORMATION DUTY CYCLE To determine the worst-case inductor ripple current, output voltage ripple, and slope compensation factor, establish the system maximum and minimum duty cycle. The duty cycle is calculated by the equation + OUT Duty Cycle where V is the diode forward drop. ...
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... Where space is limited, multiple capacitors can be placed in parallel to meet the rms current requirement. Place the input capacitor as close as possible to the IN pin of the ADP1864. OUTPUT CAPACITOR (7) The ESR and capacitance value of the output capacitor determine the amount of output voltage ripple. Δ ...
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... PFET IS TO ENSURE THAT NOISE DOES NOT COUPLE INTO THIS TRACK. 3 ISOLATED TRACK FOR CONNECTING AGND TO PGND. THIS HELPS MINIMIZE STRAY PARASITIC EFFECTS TOWARDS THE ANALOG COMPONENTS (FB AND COMPENSATION COMPONENTS). Figure 17. Bottom Layer of an Example Layout of an ADP1864 Application Rev Page COMP 1 ...
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... Load OUT 25kΩ COMP PGATE 1 6 68pF ADP1864 0.03Ω GND 80.6kΩ 174kΩ Figure 19. Application Circuit for Load OUT Rev Page 4.5V TO 5.5V IN 10µF 3.3µH 3.3V, 2.0A 47µ 3.15V TO 14V IN 10µF 5µH 2.5V, 2.0A 47µF ADP1864 ...
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... ADP1864 OUTLINE DIMENSIONS INDICATOR 0.10 MAX ORDERING GUIDE Model Temperature Range 1 ADP1864AUJZ-R7 −40°C to +125°C 2 ADP1864-EVAL 1, 2 ADP1864-EVALZ RoHS Compliant Part 2.5 V (variable 3. OUT LOAD IN 2.90 BSC 2.80 BSC 1.60 BSC PIN 1 0.95 BSC 1.90 * 0.90 BSC 0.87 0.84 * 1.00 MAX 0.20 0.08 0.50 SEATING ...
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... NOTES Rev Page ADP1864 ...
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... ADP1864 NOTES ©2005–2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05562-0-4/08(B) Rev Page ...