ADP3806 Analog Devices, Inc., ADP3806 Datasheet
ADP3806
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ADP3806 Summary of contents
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... The ADP3806 is available in three options. The ADP3806-12.6 guarantees the final battery voltage selected is 12 16.8 V ± 0.6%. The ADP3806-12.5 guarantees 12.525 V/16.7 V ± 0.6%, and the ADP3806 is adjustable using two external resistors to set the battery voltage. The current sense amplifier has rail-to-rail inputs to operate accurately under low dropout and short-circuit conditions ...
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... ADP3806 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Typical Performance Characteristics ............................................. 7 Theory of Operation ...................................................................... 10 Charge Current Control ............................................................ 10 Final Battery Voltage Control ................................................... 11 Oscillator and PWM .................................................................. Bootstrap Regulator ............................................................ 12 REVISION HISTORY 11/06— ...
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... SPECIFICATIONS @ 0°C ≤ T 100° unless otherwise noted Table 1. 1 Parameter BATTERY SENSE INPUT ADP3806-12.6 V and 16.8 V ADP3806-12.525 V and 16.7 V Input Resistance Input Current BATTERY SENSE INPUT V = 2.5 V BAT Input Current Operating Input Current Shutdown OSCILLATOR 2 Maximum Frequency 3 Frequency Variation ...
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... ADP3806 1 Parameter ISET INPUT Charge Current Programming Function Programming Function Accuracy ISET Bias Current BATSEL INPUT V = 12.6 V BAT V = 16.8 V BAT BATSEL Input Current BOOST REGULATOR OUTPUT Output Voltage 8 Output Current ANALOG REGULATOR OUTPUT Output Voltage 8 Output Current PRECISION REFERENCE OUTPUT Output Voltage ...
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... device reliability. − +25 V ESD CAUTION −0 −0 +10 V −0 −0 +0.3 V 0°C to 100°C 115°C/W 0°C to 125°C −65°C to +150°C 300°C Rev Page ADP3806 ...
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... External Compensation Node Low Current Output. 13 AGND Analog Ground. 14 BAT Battery Sense Input. 2.5 V for ADP3806. 12.525 V or 16.7 V for ADP3806-12.5. 12 16.8 V for ADP3806-12.6. 15 BATSEL Battery Voltage Sense Input. High = three cells, low = four cells. 16 ISET Charge Current Program Input. 17 CS− ...
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... TEMPERATURE (°C) Figure 6. V Accuracy vs. Temperature REF (V) CC Figure 7. V Accuracy vs. V REF CC 6.0 NO LOADS 5 100° 25°C A 4.8 4.4 4 (V) CC Figure 8. On Supply Current vs ADP3806 V = 16V CC 80 100 T = 25° 0° ...
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... ADP3806 16V 25° 250kHz OSC 500 1000 1500 2000 DRIVER LOAD CAPACITANCE (pF) Figure 9. Supply Current vs. Driver Load Capacitance 1.0 0 100°C A 0.6 0 25°C A 0.2 0 10.0 12.5 15.0 V (V) CC Figure 10. Off Supply Current vs. V 600 500 400 300 ...
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... BAT Figure 16. Conversion Efficiency vs. Battery Voltage 100 V = 19V 12.4V BAT T = 25° Figure 17. Conversion Efficiency vs. Battery Voltage at Given Temperatures V = 19V 25° Rev Page ADP3806 19V 0°C IN 19V 85° (V) BAT 14 ...
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... Li-Ion batteries, which are typically specified at 4.2 V ± 1% per cell. For a typical notebook computer battery pack, three or four cells are in series, giving a total voltage of 12 16.8 V. The ADP3806 is available in three versions, a selectable 12.525 V or 16.7 V output, a selectable 12 16.8 V output, and an adjustable output. The adjustable output can be programmed for a wide range of battery voltages using two external precision resistors ...
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... R11 R12 These resistors should have a parallel impedance of approximately 80 kΩ to minimize bias current errors. When the ADP3806 is in shutdown, an internal switch disconnects the BAT pin as shown in Figure 19. This disconnects the resistor (R11) from the battery and minimizes leakage. The resistance of the internal 1 and g 2 ...
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... This reference has source capability to power external loads if needed. LC The ADP3806 provides a low current (LC) logic output to signal when the current sense voltage (V threshold and the battery voltage is greater than 95 open-drain output that is pulled low when V threshold ...
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... SHUTDOWN A high impedance CMOS logic input is provided to turn off the ADP3806. When the voltage less than 0.8 V, the ADP3806 is placed in low power shutdown. With the exception of the system current sense amplifier, AMP2, all other circuitry is turned off. The reference and regulators are pulled to ground during shutdown and all switching is stopped ...
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... The design follows that of a buck converter. With Li-Ion cells important to have a regulator with accurate output voltage control. BATTERY VOLTAGE SETTINGS The ADP3806 has three options for voltage selection: • 12.525 V/16 selectable fixed voltages • 12.6 V/16 selectable fixed voltages • ...
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... R2) usually suffice. These time constants can be adjusted in the laboratory if required but represent a good starting point. MOSFET Selection One of the features of the ADP3806 is that it allows use of a high-side NMOS switch instead of a more costly PMOS device. The converter also uses synchronous rectification for optimal efficiency ...
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... ADP3806JRUZ-REEL7 0˚C to 100˚C ADP3806JRU-12.5-RL 0˚C to 100˚C ADP3806JRU-12.5-R7 0˚C to 100˚C 1 ADP3806JRUZ-12.5RL 0˚C to 100˚C 1 ADP3806JRUZ-12.5-R7 0˚C to 100˚C ADP3806JRU-12.6-RL 0˚C to 100˚C ADP3806JRU-12.6-R7 0˚C to 100˚C 1 ADP3806JRUZ-12.6-RL 0˚C to 100˚C 1 ADP3806JRUZ-12.6-R7 0˚C to 100˚ Pb-free. ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners ...