DIO5518D 300mA,Single Li-ion Battery Charger

Transcription

1 300mA,Single Li-ion Battery Charger Rev.0 Features Programmable Charge Current Up to 300mA Over-Temperature Protection Under oltage Lockout Protection Over oltage Lockout Protection Reverse current protection between and GND pins Automatic Recharge Threshold 4.05(Typ.) Charge Status Output Pin.9 Trickle Charge Threshold Soft-Start Limits Inrush Current Descriptions The DIO558D is a complete constant-current / constant voltage linear charger for single cell Lithium-Ion batteries. No external sense resistor is needed, and no blocking diode is required due to the internal MOSFET architecture. Thermal feedback regulates the charge current to limit the die temperature during high power operation or high ambient temperature. The charge voltage is fixed at 4., and the charge current can be programmed externally with a single resistor. The DIO558D automatically terminates the charge cycle when the charge current drops to /0 the programmed value after the final float voltage is reached. When the input supply (wall adapter or USB supply) is removed, the DIO558D automatically enters a low current state, dropping the battery drain current to less than 0.5µA. The DIO558D can be put into shutdown mode, reducing supply current to 40µA (Typ.). The DIO558D is available in a small package with DFN*-6. Standard product is Pb-Free. Ordering Information Order Part Number Top Marking Applications Wireless phone MP3/MP4 Player Bluetooth device T A Package DIO558DDN6 5D Green -40 to +85 C DFN*-6 Tape & Reel, 3000 DIO558D Rev..0

2 Pin Assignment Pin Descriptions Name PROG GND CC 3 DFN*-6 GND Figure. Top iew TEMP GHRGb Description PROG Charge current setting, charge current monitor and shutdown pin. The charging current is given by I = (/R PROG)*000. The chip will be shutdown when PROG pin floating. GND Ground. CC Power Supply. Charge Current Output. Provides charge current to the battery an regulates the final float voltage to 4.. CHRGb Open-Drain Charge Status Output. When the battery is charging, the CHARGb pin is pulled low. When the charge cycle is completed or CC is removed, the CHARGb is forced high impedance. TEMP Battery Temperature Sense Pin. When the battery temperature is too high or too low, the charging current will be terminated. GND(Expose Pad) This pin must be connected to GND, and punch to the main GND to facilitate heat dissipation.

3 Absolute Maximum Ratings Stresses beyond those listed under Absolute Maximum Rating may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other condition beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maxim rating conditions for extended periods may affect device reliability. Parameterr Rating Unit Supply oltage PROG oltage oltage CHRGb oltage Pin Current Thermal Resistance, Junction to Ambien R θja Power Dissipation Junction Temperature Operation Temperature Storage Temperature Lead Temperature (Soldering 0s) -0.3~0-0.3~CC -0.3~0-0.3~CC ~85-65~5 60 ma C/W W C C C C Recommend Operating Conditions The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended Operating conditions are specified to ensure optimal performance to the datasheet specifications. DIOO does not Recommend exceeding them or designing to Absolute Maximum Ratings. Parameterr Rating Unit Input Supply oltage Operating Temperature Range 4.5 to to 85 C

4 Electrical Characteristics CC=5, T A = 5 C (unless otherwise noted) Symbol Parameter Conditions Min. R PROG=0kΩ I SOLYCHRG Charge Mode Supply Current R PROG=0kΩ R PROG=0kΩ 90 I CHRG PROGCHRG I SPLYSTBY I STBY DIO558D Charge Mode Battery Current R PROG=0kΩ 44 R PROG=30kΩ 5 R PROG=0kΩ 0.93 PROG Pin oltage R PROG=0kΩ 0.93 Standby Mode Supply Current Charge Terminated Standby Mode Battery Current Charge Terminated 0 Typ. Max. Unit µa µa 00 0 ma ma ma µa µa I SPLYASD Shutdown Mode Supply Current CC< µa I ASD Shutdown Mode Pin Current CC< ±0.05 ± µa I SPLYULO ULO Mode Supply Current CC< U µa I ULO ULO Mode Pin Current CC< U ±0.05 ± µa I SPLYOLO OLO Mode Supply Current CC> O 40 µa I OLO OLO Mode Pin Current CC> O ±0.05 ± µa I SPLYSHUT Shutdown Mode Supply Current R PROG not Connected µa I SHUT Shutdown Mode Pin Current R PROG not Connected ±0.05 ± µa I MSD Manual Shutdown Pin Current PROG=.3 ±0.05 ± µa I SLEEP Sleep Mode Pin Current CC=0 ±0.05 ± µa I Charge_terminated 00mA/0mA charger erminated R PROG=0kΩ 0 µa Charge_terminated R PROG=0kΩ 0. FLOAT Float oltage I TRIKL Trickle Charge Current R PROG=0kΩ 0 ma TRIKL Trickle Charge oltage Threshold R PROG=0kΩ TRIKL, HYS Trickle Charge oltage Hysteresis R PROG=0kΩ 00 m ULO ULO Threshold From CC Low to High

5 Electrical Characteristics (continued) CC=5, T A= 5 C (unless otherwise noted) Symbol ULO, HYS ULO Hysteresis OLO OP_Hys MSD ASD OLO Threshold OLO Hysteresis Parameter Manual Shutdown Threshold oltage cc- Lockout Threshold oltage Δ RECHRG Auto Recharge Battery oltage 00 CHRGb T LIM CHRGb Pin Output Low oltage Junction Temperature In CT Mode DIO558D Conditions From CC Low to High PROG Pin Rising PROG Pin Falling Min. CC from low to High CC from High to Low 5 I CHRGb=5mA Typ. Max. Unit 50 m 6 80 m m m m C R ON Power FET ON Resistance 50 mω T SS Soft-Start Time R PROG=kΩ 50 µs T RECHRG Recharge Comparator Filter Time ms T TERM Termination Comparator Filter Time ms I PROG PROG Pin Pull-up Current µa TEMP_EN Battery Temperature Detectt Function TEMP Pin Rising Threshold olatge TEMP Pin Falling TEMP_H TEMP Pin High Threshold oltage TEMP Pin Rising TEMP Pin Falling % CC % CC TEMP_L TEMP Pin Low Threshold oltage TEMP Pin Rising TEMP Pin Falling % CC % CC Specifications subject to change without notice.

6 Typical Performance Characteristics CC=5, T A= 5 C (unless otherwise noted) PROG Pin oltage vs. Ambient Temperature Float oltage vs. Ambient Temperature Icharge vs. Ambient Temperature I trickle charge vs. Ambient Temperature CC Start-up CC Shut-down (CC=5, R PROG=0kΩ,C =0μF, connect to battery) (CC=5, R PROG=0kΩ,C =0μF, connect to battery)

7 Block Diagram Charging Curve (CC=5, R PROG=0kΩ,C BA AT=0μF) CC BA AT (CC=5, R PROG= =0kΩ,C =0μF) 65 C TDIE TA X 5uA 000X TEMP 80%cc 45%cc C4 C5 CA MA A R R SHDNb C R3 REF. CHRGb C R4 R5 To.9 C3 0.5μA ua cc PROG GND Figure. Function Block Diagram

8 Operation informationn The DIO558D is a single cell Lithium-Ion battery charger using a constant-current / constant-voltage algorithm. It can deliver up to 00mA of charge current with a final float voltage accuracy of ±%. The DIO558D includes an internal P-channel power MOSFET and thermal regulation circuitry. No blocking diode or external current sense resistor is required; thus, the basic charger circuit requires only two external components. Furthermore, the DIO558D is capable of operating from a USB power source. Normal charge cycle A charge cycle begins when the voltage at the CC pin rises above the ULO threshold level and a % program resistor is connected from the PROG pin to ground or when a battery is connected to the charger output. If the pin is less than..9, the charger enters trickle charge mode. In this mode, the DIO558D supplies approximately /0 the programmed charge current to bring the battery voltage up to a safe level for full current charging. When the pin voltage rises above.9, the charger enters constant-current mode, where the programmed charge current is supplied to the battery. When the pin approaches the final float voltage, the DIO558D enters constant-voltage mode and the charge current begins to decrease. The charge cycle ends when the PROG voltage is less than 00m. Programming charge current The charge current is programmed using a single resistor from the PROG pin to ground. The battery charge current of constant current mode is 000 times the current out of the PROG pin. The program resistor and the charge current of constant current are calculated using the following equations: Charge termination = R A charge cycle is terminated when the charge current falls to /0 of the programmed value after the final float voltage is reached. This condition is detected by using an internal, filtered comparator to monitor the PROG pin. When the PROG pin voltage falls below 00m for longer than T TERM (typically ms) ), charging is terminated. The charge current is latched off and the DIO558D enters standby mode, where the input supply current drops to 36µA. (Note: CC/0 termination is disabled in trickle charging mode and thermal limiting modes). When charging, transient loads on the pin can cause the PROG pin to fall below 00m for short periods of time before the DC charge current has dropped to /0 of the programmed value. The ms filter time (T TERM ) on the termination comparator ensures that transient loads of this nature do not result in premature charge cycle termination. Once the average charge current drops below /0 of the programmed value, the DIO558D terminates the charge cycle and ceases to provide any current through the pin, the chip will be put into 000 standby mode. In this state, all loads on the pin must be supplied by the battery. I CHRG PROG

9 Power ON PROG Reco mmend OR ULO Stop Shutdown Mode Charge Current :0A ICC: 50uA I:-uA CHRGb :High impedance PROG Floating OR ULO <.9 Trickle Charge Mode Charge Current: 3CC/0 CHRGb: Pull down.9<<4. Constant- Current Mode Charge Current : CC CHRGb :Pull down >=4. Constant oltage Mode Charge Current : Decrease CHRGb: Pull down PROG<00m Standby Mode Charge current: 0A ICC: 30uA I:-.5uA CHRGb :High impedance <4.0 5 Figure 3. State Diagram of a Typical Charge Cycle The DIO558D constantly monitors the pin voltage in standby mode. If this voltage drops below the 4.05 recharge threshold ( RECHRG ), another charge cycle begins and current is once again supplied to the battery. The state diagram of a typical charge cycle is as Figure 3. Charge status indicator DIO558D has an open-drain statuss indicator output CHRGb. CHRGb is pull-down when the DIO558D in a charge cycle. In other status CHRGb is in high impedance. CHRGb is in high impedance when the battery out of the normal temperature. Represent in failure state, when TEMP pin in typical connecting, and the charger with no battery: red LED don t light. The battery temperature sensee function is disabled by connecting TEMP pin to GND. If battery is not connected to charger and the pin connects a 0µF capacitor, the frequency of CHRGb flickers is about -4s.

10 Charger state Red GHRGb Charging light Battery in full state dark ULO, Battery temperature dark is outside TEMP range, battery is note connected (Use TEMP) pin is connected to Red LED flicker and 0µF and no battery mode the frequency is ~4s (TEMP=GND) Thermal Limiting An internal thermal feedback loop reduces the programmed charge current if the die temperature attempts to rise above a preset value of approximately 65 C. This feature protects the DIO558D from excessive temperature and allows the user to push the limits of the power handling capability of a given circuit board without risk of damaging the DIO558D. The charge current can be set according to typical (not worst-case) ambient temperature with the assurance that the charger will automatically reduce the current in worst-case conditions. Battery Temperature Sensing To prevent the damage caused by the very high or very low temperature done to the battery pack, the DIO558D continuously senses the battery pack temperature by measuring the voltage at TEMP pin determined by the voltage divider circuit and the battery s internal NTC thermistor. The DIO558D compares the voltage at TEMP pin ( TEMP ) against its internal LOW and HIGH thresholds to determine if charging is allowed. In DIO558D, LOW is fixed at 45% CC, while HIG GH is fixed at 80% CC. If TEMP < LOW or TEMP > HIGH, it indicates that the battery temperature is too high or too low and the charge cycle is suspended. When the TEMP is between LOW and HIGH, charging cycle resumes. The battery temperature sensing function can be disabled by connecting the TEMP pin to GND. Selecting R and R The values of R and R in the application circuit (Figure) can be determined according to the assumed temperature monitor range and thermistor s values. The Follows is an example: Assume temperature monitor range is T L ~T H, (T L <T H ); the thermistor in battery has negative temperature coefficient (NTC), R TL is thermistor s resistance at T L,R TH is the resistance at T H,so R TL >R TH,then At temperature TL, the volatge at TEMP pin is: At temperature TH, the volatge at TEMP pin is: R // R R + R // R TL TEMPL = TL CC

11 Because TEMPL = HIGH = K CC( K TEMPH = LOW = K K CC( = R Likewise, for positive temperature coefficient thermistor in battery, we have R TH >R TL and we can calculate: R = 0.8) 0.45) DIO558D R // R R + R // R TH TEMPH = TH Then we can have: RTL RTH( K K) R = ( RTL RTH) K K = R = R TL TH ( K RTL RTH( K K K) R R R = ( R ( K TH TH TH CC K) ( K K RTL( K K) RTL) K K RTH RTL( K K K) R K) ( K K TL K K ) ) We can conclude that temperature monitor range is independent of power supply voltage CC and it only depends on R, R, R TL and R TH : The values of R TH and R TL can be found in ralated battery handbook or deduced from testing data. In actual application, if only one terminal temperaturee is concerned (normally protecting overheating), there is no ennd to use R but R. It becomes very simple to calculate R in this case. Undervoltage Lockout (ULO) An internal undervoltage lockout circuit monitors the input voltage and keeps the charger in shutdown mode until CC rises above the undervoltage lockout threshold. The ULO circuit has a built-in hysteresis of 50m. Furthermore, to protect against reverse current in the power MOSFET, the ULO circuit keeps the charger in shutdown mode if CC falls to within 50m of the battery voltage. If the ULO comparator is tripped, the charger will not come out of shutdown mode until CC rises 0m above the battery voltage. Overvoltage Lockout (OLO) An internal overvoltage lockout circuit monitors the input voltage and keeps the charger in shutdown mode until CC rises above the overvoltage lockout threshold. The OLO circuit has a built-in current in the power MOSFET, the OLO circuit keeps the charger in hysteresis of 80m. Furthermore, to protect against reverse shutdown mode if CC falls to within 50m of the battery voltage. If the OLO comparator is tripped, the charger will not come out of shutdown mode until CC rises 0m above the battery voltage. Manual Shutdown At any point in the charge cycle, the DIO558D can be put into shutdown mode by removing R PROG thus floating the PROG pin. This reduces the battery drain current to less than µa and the supply current to less than 50µA. A new charge cycle can be initiated by reconnecting the program resistor. In manual shutdown, The CHRGb pin is in a high impedance state if the DIO558DD is in manual shutdown mode or in the undervoltage lockout mode: either CC is within 0m of the pin voltage or insufficient voltage is applied to the CC pin.

12 Automatic recharge CC 0µF up Figure 4. Manual Shutdown Mode Application Circuit Once the charge cycle is terminated, the DIO558D continuously monitors the voltage on the pin using a comparator with a ms filter time (T R RECHRG). A charge cycle restarts when the battery voltage falls below 4.05 (Typ.) (which corresponds to approximately 80% to 90% battery capacity). This ensures that the battery is kept at or near a fully charged condition and eliminates the need for periodic charge cycle initiations. CHRGb output enters a pull-down state during recharge cycles. 3 CC CHRGb GND TEMP R 4 Li 5 PROG 6 0µF RPROG Li-Lon

13 Application Information Typical Application CC 0µF LED R3 3 CC TEMP 5 DIO558D CHRGb PROG GND 6 4 0µF R R RPROG Li-Lon NTC Figure 5. Typical applications W/T LED indicate CC 0µF 3 CC TEMP 6 up R3 5 DIO558D CHRGb PROG 4 0µF Li-Lon GND RPROG Figure 6. Typical applications W/T microprocessor detectt Stability considerations The constant-voltage mode feedback loop is stable without an output capacitor provided a battery is connected to the charger output. With no battery present, an output capacitor is recommended to reduce ripple voltage. When using high value, low ESR ceramic capacitors, it is recommended to add a Ω resistor in series with the

14 capacitor. No series resistor is needed if tantalum capacitors are used. In constant-current mode, the PROG pin is in the feedback loop, not the battery. The constant-current mode stability is affected by the impedancee at the PROG pin. With no additional capacitance on the PROG pin, the charger is stable with program resistor values as high as 50KΩ. However, additional capacitance on this node reduces the maximum allowed program resistor thus it should be avoided. Thermal Limit An internal thermal feedback loop reduces the programmed charge current if the die temperature attempts to rise above a preset value of approximately 65 C. This feature protects the DIO558D from excessive temperature and allows the user to push the limits of the power handling capability of a given circuit board without risk of damaging the DIO558D. The charge current can be set according to typical (not worst-case) ambient temperature with the assurance that the charger will automatically reduce the current in worst-case conditions. Power dissipation The conditions that cause the DIO558D to reduce charge current through thermal feed-back can be approximated by considering the power dissipated in the IC. Nearly all of this power dissipation is generated by the internal MOSFET. This is calculated to be approximately: P D = ( CC ) I It is important to remember that DIO558D applications do not be designed for worst-case thermal conditions since the IC will automatically reduce power dissipation when the junctionn temperature reaches approximately 65 C (Constant temperature mode). CC bypass capacitor Many types of capacitors can be used for input bypass, however, caution must be exercised when using multilayer ceramic capacitors. Because of the self-resonant and high Q characteristics of some types of ceramic capacitors, a 0µF ceramic capacitor is recommended for this bypass capacitor. Due to a high voltage transient will be generated under some start-up conditions, such as connecting the charger input to a live power source. Charge current soft-start The DIO558D includes a soft-start circuit to minimize the inrush current at the start of a charge cycle. When a charge cycle is initiated, the charge current ramps from zero to the full-scale current over a period of approximately 00µs. This has the effect of minimizing the transient current load on the power supply during start-up.

15 CONTACT US Dioo is a professional design and sales corporation for high-quality and performance analog semiconductors. The company focuses on industry markets, such as, cell phone, handheld products, laptop, and medical equipment and so on. Dioo s product families include analog signal processing and amplifying, LED drivers and charger IC. Go to for a complete list of Dioo product families. For additional product information, or full datasheet, please contact with our Sales Department or Representatives.