AAT3689_08

PRODUCT DATASHEET AAT3689 BatteryManagerTM General Description The AAT3689 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 a minimum number of external components. The AAT3689 precisely regulates battery charge voltage and current for 4.2V lithium-ion/polymer battery cells. Adapter charge current rates may be programmed up to 1.0A. In the absence of an adapter and with a USB port connected, the battery can also be charged by USB power. The USB charge current can be programmed up to 500mA. 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. The AAT3689 is available in a Pb-free, thermally-enhanced, space-saving 12-pin 3x3mm TDFN package and is rated over the -40°C to +85°C temperature range. 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger Features • USB/AC Adapter System Power Charger ▪ USB: Programmable up to 500mA ▪ Adapter: Programmable up to 1.0A • 4.0V to 5.5V Input Voltage Range • Adapter Presence Automatically Disables USB Charging • High Level of Integration With Internal: ▪ Charging Devices ▪ Reverse Blocking Diodes ▪ Current Sensing • Automatic Recharge Sequencing • Battery Temperature Monitoring • Full Battery Charge Auto Turn-Off • Over-Current Protection • Over-Voltage Protection • Emergency Thermal Protection • Power On Reset and Soft Start • 12-Pin 3x3 TDFN 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 EN USB Input USB USBSET RSETUSB BATT+ BAT TS C2 10μF AAT3689 ADP Input RSETADP ADP ADPSET STAT1 BATTCT CT GND TEMP STAT2 Battery Pack 3689.2007.12.1.1 www.analogictech.com 1 PRODUCT DATASHEET AAT3689 AAT3689 BatteryManagerTM Pin Descriptions Pin # 1, 10 2 3 4 5 6 7 8 9 11 12 EP 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger Name USB BAT ADP GND EN TS STAT2 STAT1 CT USBSET ADPSET Type In In/Out In Ground In In/Out Out Out In/Out In/Out In/Out Function USB power supply input. Battery charging and sensing. Adapter power supply input. Ground connection. Enable pin. Logic high enables the IC. Connect to 10kΩ NTC thermistor. 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. Connect a resistor between this pin and GND to set the USB charging current. Connect a resistor between this pin and GND to set the adapter charging current. Exposed paddle (bottom); connect to GND directly beneath package. Pin Configuration TDFN33-12 (Top View) USB BAT ADP GND EN TS 1 2 3 4 5 6 12 11 10 9 8 7 ADPSET USBSET USB CT STAT1 STAT2 2 www.analogictech.com 3689.2007.12.1.1 PRODUCT DATASHEET AAT3689 AAT3689 BatteryManagerTM 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger Absolute Maximum Ratings1 Symbol VP VP VN TJ TLEAD Description USB, ADP, VBAT Yes Preconditioning Test VMIN > VBAT Yes Low Current Conditioning Charge Set No Yes Current Charging Mode Current Phase Test VEOC > VBAT No Yes Voltage Charging Mode Voltage Phase Test IBAT > ITERM No Charge Charge Completed Completed 12 www.analogictech.com 3689.2007.12.1.1 PRODUCT DATASHEET AAT3689 BatteryManagerTM 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger tem 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. 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 Application Information AC Adapter / USB System Power Charging Adapter Mode In the adapter mode, constant current charge levels up to 1.0A may be programmed by the user. The AAT3689 system control will always select the adapter input over the USB supply input whenever adapter voltage is present on the ADP pin. The AAT3689 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 RSETADP resistor connected between the ADPSET pin and ground. Refer to Table 1 for recommended RSETADP values for a desired constant current charge level. The precise charging function in the adapter mode may be read from the status LEDs. Please refer to the Battery Charge Status Indication discussion in this datasheet for further details. ICC 50 75 100 200 300 400 500 600 700 800 900 1000 USB RSET (kΩ) 86.6 57.6 42.2 21.0 13.7 10.2 8.06 N/A N/A N/A N/A N/A Table 1: Resistor Values. Adapter Input Charge Inhibit and Resume The AAT3689 has an under-voltage lockout and power on reset feature so that if the input supply to the adapter pin drops below the UVLO threshold the charger will suspend charging and shut down. When power is reapplied to the adapter pin or the UVLO condition recovers and VADP > 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. Enable / Disable The AAT3689 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 AAT3689 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. USB Mode The AAT3689 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 may be user programmed to any level between 50mA and 500mA by selecting the appropriate resistor values for RSETUSB. Refer to Table 1 for recommended RSETUSB values for the desired USB input constant current charge levels. Programming Charge Current The fast charge constant current charge level for both Adapter and USB input modes are programmed with set resistors placed between the ADPSET and USBSET pins and ground. The accuracy of the fast charge is dominated by the tolerance of the set resistor used. For this reason, 1% tolerance metal film resistors are recommended for the set resistor function. ADP fast charge constant current levels from 100mA to 1.0A may be set by selecting the appropriate resistor value from Table 1. The USB charge may be set to any level between 50mA and 500mA depending upon the system design requirements for a given USB charge application. Refer to Table 1 and Figure 2 for recommended RSETUSB values. USB Input Charge Inhibit and Resume The AAT3689 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 sys- 3689.2007.12.1.1 www.analogictech.com 13 PRODUCT DATASHEET AAT3689 BatteryManagerTM 10000 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger The constant current provided to charge the timing capacitor is very small, and this pin is susceptible to noise and changes in capacitance value. Therefore, the timing capacitor should be physically located on the printed circuit board layout as closely as possible to the CT pin. Since the accuracy of the internal timer is dominated by the capacitance value, 10% tolerance or better ceramic capacitors are recommended. Ceramic capacitor materials such as X7R and X5R type are a good choice for this application. 1000 IFASTCHARGE (mA) 1000 100 ADP USB 10 1 10 100 RSET (kΩ) Over-Voltage Protection An over-voltage event is defined as a condition where the voltage on the BAT pin exceeds the maximum battery charge voltage and is set by the over-voltage protection threshold (VOVP). If an over-voltage condition occurs, the AAT3689 charge control will shut down the device until voltage on the BAT pin drops below the overvoltage protection threshold (VOVP). The AAT3689 will resume normal charging operation after the over-voltage condition is removed. During an over-voltage event, the STAT LEDs will report a system fault. Figure 2: IFASTCHARGE vs. RSET. Protection Circuitry Programmable Watchdog Timer The AAT3689 contains a watchdog timing circuit for the adapter input charging mode. No watchdog timing functions are active for the USB input mode. Typically, a 0.1μF ceramic capacitor is connected between the CT pin and ground. When a 0.1μF ceramic capacitor is used, the device will time a shutdown condition if the trickle charge mode exceeds 25 minutes or the combined trickle charge plus fast charge mode exceeds three hours. When the device transitions to the constant voltage mode, the timing counter is reset and will time out after three hours and shut down the charger. Mode Trickle Charge (TC) Time Out Trickle Charge (TC) + Fast Charge (CC) Time Out Constant Voltage (VC) Mode Time Out Over-Temperature Shutdown The AAT3689 has a thermal protection control circuit which will shut down charging functions should the internal die temperature exceed the preset thermal limit threshold. Time 25 minutes 3 hours 3 hours Battery Temperature Fault Monitoring In the event of a battery over-temperature condition, the charge control will turn off the internal pass device. The STAT LEDs will display a system fault. After the system recovers from a temperature fault, the device will resume charging operation. The AAT3689 checks battery temperature before starting the charge cycle, as well as during all stages of charging. This is accomplished by monitoring the voltage at the TS pin. This system is intended to use negative temperature coefficient (NTC) thermistors, which are typically integrated into the battery package. Most commonly used NTC thermistors used in battery packs are approximately 10kΩ at room temperature (25°C). The TS pin has been specifically designed to source 80μA of current to the thermistor. The voltage on the TS pin that results from the resistive load should stay within a window from 330mV to 2.30V. If the battery becomes too hot during charging due to an internal fault, the Table 2: Summary for a 0.1μF Used for the Timing Capacitor. The CT pin is driven by a constant current source and will provide a linear response to increases in the timing capacitor value. Thus, if the timing capacitor were to be doubled from the nominal 0.1μF value, the time-out times would be doubled. If the programmable watchdog timer function is not needed, it may be disabled by connecting the CT pin to ground. The CT pin should not be left floating or unterminated, as this will cause errors in the internal timing control circuit. 14 www.analogictech.com 3689.2007.12.1.1 PRODUCT DATASHEET AAT3689 BatteryManagerTM 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger Note: Red LED forward voltage (VF) is typically 2.0V @ 2mA. For connection to the USB supply: thermistor will heat up and reduce in value, thus pulling the TS pin voltage lower than the TS1 threshold and the AAT3689 will signal the fault condition. If the use of the TS pin function is not required by the system, it should be terminated to ground using a 10kΩ resistor. RB(STAT1/2) = Example: VUSB - VF(LED) ILED(STAT1/2) Battery Charge Status Indication The AAT3689 has two status LED driver outputs. These two LEDs can indicate simple functions such as no battery charge activity, battery charging, charge complete, and charge fault. RB(STAT2) = 5.0V - 3.2V = 900Ω 2mA Status Indicator Display Simple system charging status may be displayed using one or two LEDs in conjunction with the STAT1 and STAT2 pins on the AAT3689. These two pins are simple switches to connect the LED cathodes to ground. It is not necessary to use both display LEDs if a user simply wants to have a single lamp to show “charging” or “not charging.” This can be accomplished by using the STAT1 pin and a single LED. Using two LEDs and both STAT pins simply gives the user more information to the charging states. Refer to Table 3 for LED display definitions. The LED anodes should be connected to either VUSB or VADP, depending upon the system design requirements. The LEDs should be biased with as little current as necessary to create reasonable illumination; therefore, a ballast resistor should be placed between the LED cathodes and the STAT1/2 pins. LED current consumption will add to the overall thermal power budget for the device package, so it is wise to keep the LED drive current to a minimum. 2mA should be sufficient to drive most low-cost green or red LEDs. It is not recommended to exceed 8mA for driving an individual status LED. The required ballast resistor value can be estimated using the following formulas: For connection to the adapter supply: Note: Green LED forward voltage (VF) is typically 3.2V @ 2mA. The status LED display conditions are described in Table 3. Event Description Charge Disabled or Low Supply Charge Enabled Without Battery Battery Charging Charge Completed Fault STAT1 Off Flash1 On Off On STAT2 Off Flash1 Off On On Table 3: Status LED Display Conditions. Capacitor Selection Input Capacitor In general, it is good design practice to place a decoupling capacitor between the ADP and USB pins and ground. An input capacitor in the range of 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 AAT3689 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. RB(STAT1/2) = Example: VADP - VF(LED) ILED(STAT1/2) RB(STAT1) = 5.5V - 2.0V = 1.75kΩ 2mA 1. Flashing rate depends on output capacitance. 3689.2007.12.1.1 www.analogictech.com 15 PRODUCT DATASHEET AAT3689 BatteryManagerTM Output Capacitor The AAT3689 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 AAT3689 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. 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger Printed Circuit Board Layout Considerations For the best results, it is recommended to physically place the battery pack as close to the AAT3689 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 AAT3689 TDFN package, 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. AAT3689 Evaluation Board Layout Figure 3: AAT3689 Evaluation Board Component Side Layout. Figure 4: AAT3689 Evaluation Board Solder Side Layout. 16 www.analogictech.com 3689.2007.12.1.1 PRODUCT DATASHEET AAT3689 BatteryManagerTM 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger ON/OFF J1 123 AAT3689 Evaluation Board Schematic Diagram DS1 (b) USB GRN LED D2 J2 0 U1 5 1 3 2 10 7 8 11 12 4 BAV74LT1 DS1 (a) BAV74LT1 RED LED D1 ADP EN USB ADP BAT TS CT AAT3689 USB STAT2 STAT1 USBSET ADPSET GND R5 1.5K R4 1.5K BAT TS C1 10μF C2 10μF C3 10μF R3 10K CT C4 0.1μF 6 9 R1 8.06K R2 8.06K AAT3689 Evaluation Board Bill of Materials Component U1 R1, R2 R3 R4, R5 C1, C2, C3 C4 JP1 JP2 D1 D2 DS1 (a, b) Part Number AAT3689IFP-4.2-T1 Chip Resistor Chip Resistor Chip Resistor GRM21BR61A106KE19 GRM188R71C104KA01 PRPN401PAEN Chip Resistor CMD15-21SRC/TR8 CMD15-21VGC/TR8 BAV74LT-A Description 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger;12-Pin 3x3 TDFN Package 8.06KΩ, 1%, 1/4W; 0603 10KΩ, 5%, 1/4W; 0603 1.5KΩ, 5%, 1/4W; 0603 CER 10μF 10V 10% X5R 0805 CER 0.1μF 16V 10% X7R 0603 Conn. 3-pin Header, 2mm zip 0Ω Red LED; 1206 Green LED; 1206 Default Diode; SOT23-3 Manufacturer AnalogicTech Vishay Vishay Vishay Murata Murata Sullins Electronics Vishay Chicago Miniature Lamp Chicago Miniature Lamp On Semi 3689.2007.12.1.1 www.analogictech.com 17 PRODUCT DATASHEET AAT3689 AAT3689 BatteryManagerTM 0.5A/1.0A USB Port/Adapter Lithium-Ion/Polymer Battery Charger Ordering Information Package TDFN33-12 Marking1 RQXYY Part Number (Tape and Reel)2 AAT3689IWP-4.2-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/about/quality.aspx. Package Information3 TDFN33-12 Index Area Detail "A" 0.43 ± 0.05 0.1 REF 3.00 ± 0.05 2.40 ± 0.05 C0.3 0.45 ± 0.05 Pin 1 Indicator (optional) 3.00 ± 0.05 1.70 ± 0.05 Top View Bottom View Detail "A" 0.75 ± 0.05 0.05 ± 0.05 Side View All dimensions in millimeters. 1. XYY = assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD. 3. The leadless package family, which includes QFN, TQFN, DFN, TDFN and STDFN, has exposed copper (unplated) at the end of the lead terminals due to the manufacturing process. A solder fillet at the exposed copper edge cannot be guaranteed and is not required to ensure a proper bottom solder connection. Advanced Analogic Technologies, Inc. 3230 Scott Boulevard, Santa Clara, CA 95054 Phone (408) 737-4600 Fax (408) 737-4611 © 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. Except as provided in AnalogicTech’s terms and conditions of sale, AnalogicTech assumes no liability whatsoever, and AnalogicTech disclaims any express or implied warranty relating to the sale and/or use of AnalogicTech products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. In order to minimize risks associated with the customer’s applications, adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. 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. 18 www.analogictech.com 0.23 ± 0.05 0.23 ± 0.05 3689.2007.12.1.1