AAT2550_08 ANALOGICTECH [Advanced Analogic Technologies], AAT2550_08 Datasheet

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SystemPower TM General Description The AAT2550 is a fully integrated total power solution with two step-down converters plus a single-cell lithium- ion / polymer battery charger. The step-down converter input voltage range spans 2.7V to 5.5V, making the AAT2550 ideal ...

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SystemPower SystemPower TM TM Pin Descriptions Pin # Symbol Function Enable pin for Converter A. When connected to logic low, it disables the step-down converter and con- 1 ENA sumes less than 1μA of current. When connected to logic high, ...

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SystemPower SystemPower TM TM Absolute Maximum Ratings Symbol Description INA, INB, and ADP Voltages to GND INA/B ADP and V LXA/B FBA/B LXA LXB FBA V Voltage on ...

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SystemPower SystemPower TM TM Electrical Characteristics V = 3.6V -40°C to +85°C, unless otherwise noted. Typical values are Symbol Description Step-Down Converters A and B V Input Voltage IN V Under-Voltage Lockout Threshold UVLO ...

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SystemPower SystemPower TM TM Electrical Characteristics -40°C to +85°C, unless otherwise noted. Typical values are at T ADP A Symbol Description Battery Charger V Adapter Voltage Range ADP Under-Voltage Lockout V UVLO UVLO Hysteresis I ...

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SystemPower SystemPower TM TM Typical Characteristics — Step-Down Converter Efficiency vs. Load = 1.8V 4.7μ μ OUT 100 0.1 ...

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SystemPower SystemPower TM TM Typical Characteristics — Step-Down Converter (continued) Soft Start (V = 3.6V 1.8V 400mA) IN OUT OUT 5 4 3.0 2.0 1.0 0 Time (100μ μ s/div) ...

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SystemPower SystemPower TM TM Typical Characteristics — Step-Down Converter (continued) P-Channel R vs. Input Voltage DS(ON) 750 700 650 120°C 100°C 600 550 85°C 500 450 25°C 400 350 300 2.5 3.0 3.5 4.0 4.5 Input Voltage (V) Load Transient ...

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SystemPower SystemPower TM TM Typical Characteristics — Step-Down Converter (continued) Line Response (V = 1.8V @ 400mA) OUT 1.82 1.81 1.80 Time (25µs/div) Output Ripple (V = 3.6V 1.8V 400mA) IN OUT OUT ...

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SystemPower SystemPower TM TM Typical Characteristics — Battery Charger Constant Charging Current vs. R 10000 1000 100 (kΩ Ω SET End of Charge Voltage Regulation vs. Temperature 4.242 4.221 4.200 4.179 4.158 -50 -25 0 ...

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SystemPower SystemPower TM TM Typical Characteristics — Battery Charger (continued) Charging Current vs. Battery Voltage (ADPSET = 8.06kΩ Ω 5.0V) IN 1.2 1.0 0.8 0.6 0.4 0.2 0.0 2.5 2.9 3.3 3.7 Battery Voltage (V) V vs. ...

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SystemPower SystemPower TM TM Typical Characteristics — Battery Charger (continued) CT Pin Capacitance vs. Counter Timeout 2.0 1.8 1.6 1.4 Precondition Timeout 1.2 1.0 0.8 Precondition + Constant Current Timeout 0.6 or Constant Voltage Timeout 0.4 0.2 0 ...

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SystemPower SystemPower TM TM Functional Block Diagram ADP ADPSET 4.2V ENBAT STAT2 STAT1 CT FBA Voltage Reference ENA FBB Voltage Reference ENB Functional Description The AAT2550 is a highly integrated power management IC comprised of a battery charger and two ...

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SystemPower TM charge control will enter into thermal regulation. When the system thermal regulation becomes active, the pro- grammed constant current charge amplitude will auto- matically decrease to a safe level for the present operat- ing conditions. If the ambient ...

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SystemPower TM Fast Charge/Constant Current Charging Battery preconditioning continues until the voltage on the BAT pin exceeds the preconditioning voltage thresh- old ( this point, the charger begins the constant MIN current fast charging phase. The fast charge ...

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SystemPower SystemPower TM TM System Operation Flow Chart Yes Total Power Solution for Portable Applications Total Power Solution for Portable Applications Yes No Enable Timing Yes Expire No No Yes No Yes BAT_EOC No Yes TERM No ...

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SystemPower TM Application Information AC Adapter Power Charging The adapter constant current charge levels can be pro- grammed up to 1A. The AAT2550 will operate from the adapter input over a 4.0V to 5.5V range. The constant current fast charge ...

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SystemPower TM 10000 1000 100 (kΩ Ω SET Figure 2: Constant Charging Current vs. R Protection Circuitry Programmable Watchdog Timer The AAT2550 contains a watchdog timing circuit for the adapter input charging mode. Typically, a ...

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SystemPower TM If the use of the TS pin function is not required by the system, it should be terminated to ground with a 10kΩ resistor. Battery Charge Status Indication The AAT2550 indicates the status of the battery under charge ...

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SystemPower TM The DATA pin function is active low and should normally be pulled high This data line may also be pulled ADP high to the same level as the high state for the logic I/O port ...

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SystemPower TM Capacitor Selection Input Capacitor In general good design practice to place a decou- pling capacitor between the ADP pin and ground. An input capacitor in the range of 1μF to 22μF is recom- mended. If the ...

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SystemPower TM Thermal protection completely disables switching when internal dissipation becomes excessive. The junction over-temperature threshold is 140°C with 15°C of hys- teresis. Once an over-temperature or over-current fault conditions is removed, the output voltage automatically recovers. Under-Voltage Lockout Internal ...

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SystemPower TM for · RMS(MAX) 2 ⎛ ⎞ · The term appears in both the input voltage ⎝ ⎠ ripple ...

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SystemPower TM R7 59kΩ V (V) R8, R10 (kΩ) OUT 0.8 19.6 0.9 29.4 1.0 39.2 1.1 49.9 1.2 59.0 1.3 68.1 1.4 78.7 1.5 88.7 1.8 118 1.85 124 2.0 137 2.5 187 3.3 267 Table 6: ...

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SystemPower TM Battery Charger Losses The maximum battery charger loss is · ADP MIN Total Charger Dissipation Adapter Voltage ADP V = Preconditioning Voltage ...

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SystemPower TM Printed Circuit Board Layout Use the following guidelines to ensure a proper printed circuit board layout. 1. Step-down converter bypass capacitors (C4 and C5 in Figure 4) must be placed as close as possible to the step-down converter ...

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SystemPower SystemPower TM TM VIN GND EnVoA R10 118k VoA L2 4.7μH C8 4.7μF Data SW1 Data Strobe R3 VoA, VoB (V) 1.0 1.2 1.5 VoA 1.8 VoB 2.5 3.0 3.3 Figure 4: AAT2550 Evaluation Board Schematic. ...

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SystemPower SystemPower TM TM Figure 5: AAT2550 Evaluation Board Top Side Layout. Figure 7: AAT2550 Evaluation Board Layer 3 Layout Total Power Solution for Portable Applications Total Power Solution for Portable Applications Figure 6: AAT2550 Evaluation Board Layer ...

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SystemPower SystemPower TM TM Qty. Description 1 Conn. Term Block 2.54mm 2 POS 1 Conn. Term Block 2.54mm 3 POS 3 Ceramic Capacitor 10μF 10%, 10V, X5R, 0805 2 Ceramic Capacitor 4.7μF 10%, 6.3V, X5R, 0805 1 Ceramic Capacitor 0.1μF ...

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SystemPower SystemPower TM TM Adjustable Version (0.6V device) V (V) OUT 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.8 1.85 2.0 2.5 3.3 Table 10: Evaluation Board Component Values. 1. For reduced quiescent current, R7 and R9 = 221kΩ. ...

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SystemPower SystemPower TM TM Step-Down Converter Design Example Specifications V = 2.5V @ 400mA (V = 0.6V), pulsed load ΔI OA FBA V = 1.8V @ 400mA (V = 0.6V), pulsed load ΔI OB FBB V = 2.7V to 4.2V ...

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SystemPower SystemPower TM TM 2.5V Output Capacitor 3 · ΔI 3 · 0.3A LOAD 3.2μF OUT V · F 0.2V · 1.4MHz DROOP · OUT IN(MAX) OUT I = ...

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SystemPower SystemPower TM TM Ordering Information Voltage Package Converter 1 QFN44-24 0.6V All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor products that are in compliance with current RoHS standards, including the requirement that lead not ...

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SystemPower SystemPower TM TM Package Information Pin 1 Dot By Marking 4.000 ± 0.050 Top View All dimensions in millimeters. 1. The leadless package family, which includes QFN, TQFN, DFN, TDFN and STDFN, has exposed copper (unplated) at the end ...