AAT3686IXN-4.2-T1

USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger General Description The AAT3686 BatteryManager is a highly integrated single-cell lithium-ion/polymer battery charger IC designed to operate with USB port and AC adapter inputs. It requires the minimum number of external components. The AAT3686 precisely regulates battery charge voltage and current for 4.2V lithium-ion/polymer battery cells. Adapter charge current rates can be programmed up to 1.5A. In the absence of an adapter and with a USB port connected, the battery can also be charged by USB power. Depending on the USB port type, the AAT3686 charge current can be programmed for two separate levels up to 500mA. An optional Charge Reduction Loop is also built in to allow users to charge the battery with available current from a USB port, while keeping the port voltage regulated. USB charging is disabled when an adapter is present. Battery temperature and charge state are fully monitored for fault conditions. In the event of an over-voltage or over-temperature failure, the device will automatically shut down, thus protecting the charging device, control system, and the battery under charge. Status monitor output pins are provided to indicate the battery charge status by directly driving two external LEDs. A serial interface output is available to report 22 various status states to a microcontroller. The AAT3686 is available in a Pb-free, thermallyenhanced, space-saving TDFN34-16 (3x4mm) or TDFN44-16 (4x4mm) package and is rated over the -40°C to +85°C temperature range. AAT3686 Features • BatteryManager™ • • • • • • • • • • • • • USB Port/AC Adapter System Power Charger — USB: Programmable to 500mA for USB Hi/Lo — Adapter: Programmable to 1.5A Max 4.0V to 5.5V Input Voltage Range Adapter Present Indicator (ADPP# Pin) Adapter Presence Automatically Disables USB Charging High Level of Integration With Internal: — Charging Devices — Reverse Blocking Diodes — Current Sensing Automatic Recharge Sequencing Digital Thermal Regulation in ADP Charge Charge Reduction Loop in USB Charge Battery Temperature Monitoring Full Battery Charge Auto Turn-Off Over-Voltage and Emergency Thermal Protection Power On Reset and Soft Start Serial Interface Status Reporting TDFN34-16 or TDFN44-16 Package Applications • • • • • • Cellular Telephones Digital Still Cameras Hand-Held PCs MP3 Players Personal Data Assistants (PDAs) Other Lithium-Ion/Polymer Battery-Powered Devices Typical Application Enable USB Input USB Hi/Lo Select USB USBSEL USBH RSETH RSETL USBL EN CHR BATT+ BAT TS CT CT C2 10μF AAT3686 BATT- ADP Present ADP Input RSET ADPP# ADP ADPSET STAT1 GND DATA STAT2 TEMP Battery Pack Serial Data 3686.2006.10.1.9 1 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger Pin Descriptions Pin # (TDFN34-16/ TDFN44-16) 1 2 3 4 5 AAT3686 Name USB BAT ADP GND CHR Type In In/Out In Ground In/Out Function USB power supply input. Battery charging and sensing. Adapter input. Ground connection. Resistor divider to set USB voltage regulation for charge reduction mode. Leave this pin open for default 4.5V USB regulation point. Tie to USB pin to disable this function. Enable pin. Logic high enables the IC. Adapter present indicator. This pin is open drain until ADP pin reaches threshold. Connect to 10kΩ NTC thermistor. Status report to microcontroller via serial interface, open-drain. Battery charge status indicator pin to drive an LED: active low, open-drain. Battery charge status indicator pin to drive an LED: active low, open-drain. Timing capacitor to adjust internal watchdog timer. Set maximum charge time for adapter powered trickle, CC, and CV charge modes. The watchdog timer only sets the timers for adapter battery charging; there is no timeout for the battery charging from the USB input. If timing function is not needed, terminate this pin to ground. When USB is present, use this pin to toggle between 100mA and 500mA limit. Connect resistor here to set charge current for low-current USB port. Connect resistor here to set charge current for high-current USB port. Use resistor at this pin to set adapter charging current. Exposed paddle (bottom); connect to GND directly beneath package. 6 7 8 9 10 11 12 EN ADPP# TS DATA STAT2 STAT1 CT In Out In/Out In/Out Out Out In/Out 13 14 15 16 EP USBSEL USBL USBH ADPSET In In/Out In/Out In/Out Pin Configuration TDFN34-16 (Top View) TDFN44-16 (Top View) USB BAT ADP GND CHR EN ADPP# TS 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 ADPSET USBH USBL USBSEL CT STAT1 STAT2 DATA USB BAT ADP GND CHR EN ADPP# TS 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 ADPSET USBH USBL USBSEL CT STAT1 STAT2 DATA 2 3686.2006.10.1.9 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger AAT3686 Feature Options Product AAT3686 AAT3686-1 AAT3686 Internal Pull-Up Resistor on EN Pin No Yes Can Leave TS Pin Open No Yes Absolute Maximum Ratings1 Symbol VP VP VN TJ TLEAD Description USB, ADP Input Voltage, VUVLO Yes Switch On No USB Enable 0 No Sleep Mode Power On Reset USB Low Current Loop USB Detect USBSEL = ? Thermal Loop Enable No Timing Device Temp. Monitor TJ > 110°C Yes USB High Current Loop 1 Fault Conditions Monitor OV, OT Yes No Battery Temp. Monitor VTS1 < TS < VTS2 No Yes Thermal Loop Current Reduction in ADP Charging Mode Shutdown Mode Battery Temp. Fault Expire Charge Safety Timer Timer No Yes Preconditioning Test VMIN > VBAT Yes Low Current Conditioning Charge Set Recharge Test VRCH > VBAT No Yes Current Charging Mode Current Phase Test VEOC > VBAT No Yes Voltage Charging Mode Voltage Phase Test IBAT > ITERM No Charge Completed USB Loop Current Reduction in USB Charging Mode Yes No USB Voltage Regulation Enable USB Voltage Test VUSB < 4.5V 12 3686.2006.10.1.9 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger Application Information AC Adapter / USB System Power Charging Adapter Mode In the adapter mode, constant current charge levels up to 1.5A can be programmed by the user. The AAT3686 system control will always select the adapter input over the USB supply input whenever adapter voltage is present on the ADP pin. The AAT3686 will operate from the adapter input over a 4.0V to 5.5V range. The constant current fast charge current for the adapter input mode is set by the RSET resistor connected between the ADPSET and ground. Refer to Table 1 for recommended RSET values for a desired constant current charge level. The presence of voltage on the adapter input is indicated by the ADPP# pin function. This indicator pin is an open drain and will pull the ADPP# pin low when voltage is detected on the ADP pin. The precise charging function in the adapter mode may be read from the DATA pin and/or status LEDs. Please refer to the Battery Charge Status Indication discussion in this datasheet for further details on data reporting. Thermal Loop Control Due to the integrated nature of the linear charging control pass device for the adapter mode, a special thermal loop control system has been employed to maximize charging current under all operation conditions. The thermal management system measures the internal circuit die temperature and reduces the fast charge current when the device exceeds a preset internal temperature control threshold. Once the thermal loop control becomes active, the fast charge current is initially reduced by a factor of 0.44. The initial thermal loop current can be estimated by the following equation: controls the system charge level; therefore, the AAT3686 will always provide the highest level of constant current in the fast charge mode possible for any given ambient temperature condition. Adapter Input Charge Inhibit and Resume The AAT3686 has an under-voltage lockout and power on reset feature so that the charger will suspend charging and shut down if the input supply to the adapter pin drops below the UVLO threshold. When power is re-applied to the adapter pin or the UVLO condition recovers and ADP > VBAT, the system charge control will assess the state of charge on the battery cell and will automatically resume charging in the appropriate mode for the condition of the battery. USB Mode The AAT3686 provides an input for intelligent USB charging. When no voltage is present on the adapter input pin, the charge controller will automatically switch to accepting power from the USB input. The USB charge mode provides two programmable fast charge levels up to 500mA each, USB high and USB low, USBH and USBL, respectively. The USBH or USBL modes may be externally selected by the USB select pin (USBSEL). USBSEL is internally pulled low through a 1MΩ resistor. When the USBSEL pin is connected to a logic high level, the USBH level will be active. Conversely, when USBSEL is pulled to a logic low level (ground), the USBL level will be used for charging. Typically, USBH is set for 500mA and USBL is set for 100mA. However, these two USB charge levels may be user programmed to any level between 50mA and 500mA by selecting the appropriate resistor values for RSETH and RSETL. Refer to Table 1 for recommended RSETH and RSETL values for the desired USB input constant current charge levels. USB Charge Reduction In many instances, product system designers do not know the real properties of a potential USB port used to supply power to the battery charger. Typically, powered USB ports found on desktop and notebook PCs should supply up to 500mA. In the event a USB port being used to supply the charger is unable to provide the programmed fast charge current or if the system under charge must also share supply current with other functions, the AAT3686 will automatically reduce USB fast charge current to maintain port integrity and protect the host system. 13 AAT3686 ITLOOP = ICC · 0.44 The thermal loop control re-evaluates the circuit die temperature every three seconds and adjusts the fast charge current back up in small steps to the full fast charge current level or until an equilibrium current is discovered and maximized for the given ambient temperature condition. The thermal loop 3686.2006.10.1.9 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger AAT3686 ICC 50 75 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 ADP RSET (kΩ) N/A N/A 84.5 43.2 28.0 21.0 16.9 13.3 11.5 10.2 9.09 8.06 7.32 6.65 6.04 5.62 5.36 USBH RSET (kΩ) 86.6 57.6 42.2 21.0 13.7 10.2 8.06 6.65 5.62 4.87 4.32 3.83 3.48 3.16 2.87 2.67 2.43 USBL RSET (kΩ) 86.6 57.6 42.2 20.5 13.7 10.2 8.06 6.65 5.62 4.87 4.32 3.83 3.48 3.16 2.87 2.67 2.43 VUSB USB R11 1.025M CHR VCHR = 2.0V 825k R12 Figure 2: Internal Equivalent Circuit for the CHR Pin. Table 1: Resistor Values. The USB charge reduction system becomes active when the voltage on the USB input falls below the USB charge reduction threshold (VUSBCHR), which is typically 4.5V. Regardless of which USB charge function is selected (USBH or USBL), the charge reduction system will reduce the fast charge current level in a linear fashion until the voltage sensed on the USB input recovers above the charge reduction threshold voltage. The USB charge reduction threshold (VUSBCHR) can be externally set to a value lower than 4.5V by placing a resistor divider network between VUSB and ground with the center connected to the CHR pin. The USB charge reduction feature can be disabled by connecting a 10kΩ resistor from the CHR pin directly to the USB input pin (see Figure 2). The following equation can be used to approximate a USB charge reduction threshold below 4.5V: USB Input Charge Inhibit and Resume The AAT3686 UVLO and power on reset feature will function when the USB input pin voltage level drops below the UVLO threshold. At this point, the charger will suspend charging and shut down. When power is re-applied to the USB pin or the UVLO condition recovers, the system charge control will assess the state of charge on the battery cell and will automatically resume charging in the appropriate mode for the condition of the battery. Enable / Disable The AAT3686 provides an enable function to control the charger IC on and off. The enable (EN) pin is active high. When pulled to a logic low level, the AAT3686 will be shut down and forced into the sleep state. Charging will be halted regardless of the battery voltage or charging state. When the device is re-enabled, the charge control circuit will automatically reset and resume charging functions with the appropriate charging mode based on the battery charge state and measured cell voltage. VUSBCHR = 2.0V ÷ Where R11/R12 2 PDATA N=1 N=2 N=3 Thermal Considerations The AAT3686 is offered in a 3x4mm TDFN package and a 4x4mm TDFN package, each of which can provide up to 2.7W of power dissipation when it is properly bonded to a printed circuit board and has a maximum thermal resistance of 37°C/W. Many considerations should be taken into account when designing the printed circuit board layout, as well as the placement of the charger IC package in proximity to other heat generating devices in a given application design. The ambient temperature around the charger IC will also have an effect on the thermal limits of a battery charging application. The maximum limits that can be expected for a given ambient condition can be estimated by the following discussion: First, the maximum power dissipation for a given situation should be calculated: Eq. 1: PD = [(VIN - VBAT) · ICC + (VIN · IOP)] VBAT = Battery voltage as seen at the BAT pin ICC IOP = Maximum constant fast charge current programmed for the application = Quiescent current consumed by the charger IC for normal operation Next, the maximum operating ambient temperature for a given application can be estimated based on the thermal resistance of the 3x4mm and 4x4mm TDFN packages when sufficiently mounted to a PCB layout and the internal thermal loop temperature threshold. Eq. 2: TA = TJ - (θJA · PD) Where: TA TJ PD θJA = Ambient temperature in degrees C = Maximum device junction temperature below the thermal loop threshold = Total power dissipation by the device = Package thermal resistance in °C/W Where: PD VIN = Total power dissipation by the device = Either VADP or VUSB, depending on which mode is selected 3686.2006.10.1.9 19 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger Example: For an application where the fast charge current for the adapter mode is set to 1A, VADP = 5.0V, and the worst case battery voltage is 3.0V, what is the maximum ambient temperature where the thermal limiting will become active? Given: VADP = 5.0V VBAT = 3.0V ICC IOP TJ θJA = 1A = 0.75mA = 110°C = 37°C/W 1µF to 22µF is recommended. If the source supply is unregulated, it may be necessary to increase the capacitance to keep the input voltage above the under-voltage lockout threshold during device enable and when battery charging is initiated. If the AAT3686 adapter input is to be used in a system with an external power supply source, such as a typical AC-to-DC wall adapter, then a CIN capacitor in the range of 10µF should be used. A larger input capacitor in this application will minimize switching or power bounce effects when the power supply is "hot plugged." Likewise, a 10µF or greater input capacitor is recommended for the USB input to help buffer the effects of USB source power switching, noise, and input cable impedance. Output Capacitor The AAT3686 only requires a 1µF ceramic capacitor on the BAT pin to maintain circuit stability. This value should be increased to 10µF or more if the battery connection is made any distance from the charger output. If the AAT3686 is to be used in applications where the battery can be removed from the charger, such as in the case of desktop charging cradles, an output capacitor greater than 10µF may be required to prevent the device from cycling on and off when no battery is present. AAT3686 Using Equation 3, calculate the device power dissipation for the stated condition: Eq. 3: PD = (5.0V - 3.0V)(1A) + (5.0V · 0.75mA) = 2.00375W The maximum ambient temperature before the AAT3686 thermal loop becomes active can now be calculated using Equation 4: Eq. 4: TA = 110°C - (37°C/W · 2.00375W) = 35.86°C Printed Circuit Board Layout Considerations For the best results, it is recommended to physically place the battery pack as close to the AAT3686 BAT pin as possible. To minimize voltage drops on the PCB, keep the high current carrying traces adequately wide. For maximum power dissipation of the AAT3686 TDFN packages, the metal substrate should be solder bonded to the board. It is also recommended to maximize the substrate contact to the PCB ground plane layer to further increase local heat dissipation. Refer to the AAT3686 evaluation board for a good layout example. = 35.86°C Therefore, under the stated conditions for this worst case power dissipation example, the AAT3686 will enter the thermal loop and lower the fast charge constant current when the ambient operating temperature rises above 35.86°C. Capacitor Selection Input Capacitor In general, it is good design practice to place a decoupling capacitor between the VADP and VUSB pins and ground. An input capacitor in the range of 20 3686.2006.10.1.9 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger AAT3686 Evaluation Board Schematic Diagram AAT3686 Figure 5: AAT3686 Evaluation Board Component Side Layout. Figure 6: AAT3686 Evaluation Board Solder Side Layout. ON/OFF J1 3 2 1 Figure 7: AAT3686 Evaluation Board Assembly Layout. USBSEL J2 3 2 1 HI D4 (b) USB BAV74LT1 D4 (a) BAV74LT1 LO D3 RED LED GREEN RED LED LED D2 D1 ADP R9 1.5K R7 1.5K U1 1 3 2 R8 1.5K R10 1.5K R6 R11 Open Open AAT3686 USBSEL STAT2 STAT1 DATA USBH USBL ADPSET CT 12 13 10 11 9 15 14 16 USB ADP BAT EN CHR ADPP# TS BAT 6 5 7 DATA SW1 C1 10μF C2 10μF C3 10μF R12 R1 Open 10K 8 R3 R5 R4 C6 GND 4 8.06K 42.2K 8.06K Open (Optional) C5 0.1μF TS CT Figure 8: AAT3686 Evaluation Board Schematic Diagram. 3686.2006.10.1.9 21 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger AAT3686 Evaluation Board Bill of Materials (BOM) Quantity Description 2 2 1 1 3 AAT3686 Desig. Footprint Manufacturer Mill-Max Phoenix Contact Phoenix Contact Hirose Electronic Co., Ltd. Murata Part # 6821-0-0001-00-00-08-0 277-1274-ND 277-1273-ND H2959CT-ND 490-1717-1-ND 1 2 1 1 2 1 1 1 4 1 1 Test Pin TS, CT Conn Term Block USB, GND/ TBLOK2 2.54mm 2POS ADP, GND Conn Term Block BAT, TS, TBLOK3 2.54mm 3POS GND USB 2.0 Receptacle, USB USB-MINI-B 5POS Capacitor, Ceramic, C1, 2, 3 0805 10µF 6.3V 10% X5R 0805 Capacitor, Ceramic, C5 0603 0.1µF 25V 10% X5R 0603 Typical Red LED D1, D3 1206LED Typical Green LED D2 1206LED Switching Diode D4 a, b SOT23-3 Header, 3-Pin J1, 2 Header 2mm-3 RES 10kΩ 1/16W R1 0603 5% 0603 SMD RES 8.06kΩ 1/16W R3, 4 0603 1% 0603 SMD RES 42.2kΩ 1/16W R5 0603 1% 0603 SMD RES 1.5kΩ 1/16W R7, 8, 0603 5% 0603 SMD 9, 10 Switch Tact 6mm SW1 Switch SPST H = 5.0mm AAT3686 USB Port/AC U1 TDFN34-16; Adapter Lithium-Ion/ TDFN44-16 Polymer Battery Charger Murata 478-1244-2-ND Chicago Miniature Lamp Chicago Miniature Lamp On Semi Sullins Panasonic/ECG Panasonic/ECG Panasonic/ECG Panasonic/ECG ITT Industries/C&K Div AnalogicTech CMD15-21SRC/TR8 CMD15-21SRC/TR8 BAV74LT1 6821-0-0001-00-00-08-0 P10KJTR-ND P9.76KHCT-ND P42.2KHTR-ND P1.5KCGCT-ND CKN9012-ND AAT3686IRN-4.2 AAT3686IXN-4.2 22 3686.2006.10.1.9 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger Ordering Information Package TDFN34-16 TDFN44-16 TDFN44-16 AAT3686 Marking1 PHXYY PHXYY SKXYY Part Number (Tape and Reel)2 AAT3686IRN-4.2-T1 AAT3686IXN-4.2-T1 AAT3686IXN-4.2-1-T1 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 exceed 0.1% by weight in homogeneous materials. For more information, please visit our website at http://www.analogictech.com/pbfree. Package Information TDFN34-16 Index Area (D/2 x E/2) Detail "B" 4.00 ± 0.05 0.20 MIN 0.35 ± 0.10 0.075 ± 0.075 Detail "A" 3.00 ± 0.05 Top View Bottom View Pin 1 Indicator (optional) 7.5° ± 7.5° 0.85 MAX Detail "B" 0.05± 0.05 0.229 ± 0.051 Option A: C0.30 (4x) max Chamfered corner Option B: R0.30 (4x) max Round corner Side View Detail "A" All dimensions in millimeters. 1. XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD. 3686.2006.10.1.9 0.21 ± 0.05 23 USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger TDFN44-16 Index Area (D/2 x E/2) Detail "B" AAT3686 4.00 ± 0.05 3.30 ± 0.05 0.3 ± 0.10 0.16 0.375 ± 0.125 0.075 ± 0.075 0.1 REF Detail "A" Top View Bottom View Pin 1 Indicator (optional) 7.5° ± 7.5° + 0.05 0.8 -0.20 0.229 ± 0.051 Detail "B" Option A: C0.30 (4x) max Chamfered corner Option B: R0.30 (4x) max Round corner 0.05 ± 0.05 Side View Detail "A" All dimensions in millimeters. © Advanced Analogic Technologies, Inc. AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights, or other intellectual property rights are implied. AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice. Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability. AnalogicTech warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with AnalogicTech’s standard warranty. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other brand and product names appearing in this document are registered trademarks or trademarks of their respective holders. Advanced Analogic Technologies, Inc. 830 E. Arques Avenue, Sunnyvale, CA 94085 Phone (408) 737-4600 Fax (408) 737-4611 24 3686.2006.10.1.9 0.23 ± 0.05 0.45 ± 0.05 4.00 ± 0.05 2.60 ± 0.05