FC5754 FS | Alldatasheet

Document overview

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Technical content

Features

 Programmable charge current up to 1A  No MOSFET, sense resistor or blocking diode required  Complete linear charger both in SOT-23-5 and E-SOP-8 for single cell Lithium-ion batteries  Typical zero reverse current from battery  Thermal regulation maximizes charge rate without risk of overheating  Charges single cell Li-ion batteries directly from USB port  Act as a LDO when battery is removed  Preset 4.2V/4.35V charge voltage with ±1% accuracy  Automatic recharge  Charge status indicator  C/10 charge termination  45uA shutdown supply current  2.9V trickle charge threshold  Soft-start limits inrush current  RoHS compliant and Pb-free

Applications

 Wireless handsets  Hand-held instruments  Portable information appliances  Bluetooth application  Charging docks and cradles  Typical Application Diagram  Typical Performance Characteristics IBAT (mA) Complete Charge Cycle (850mAh Battery) 580 mA Charger LDO Mode (Battery Removed) Time (1000s/DIV) VBAT (V)

  1. 11. 04 2/19Revision No : 0 Pin Configuration SOT-23-5(Top View) E-SOP-8(Top View) Order information FC5754--XXVF05GRR XX Charger Voltage VF05 SOT-23-5 Packa ge GRR RoHS &Halo gen free Rating: -40 to 85°C Package in Tape & Reel FC5754-xxSG08NRR xx Charger Voltage NRR RoHS & Halogen free package Rating: -40 to 85°C Package in Tape & Reel Order, Mark & Packing Information Charge Voltage Package Marking Product ID Packing 4.2V SOT-23-5 FC5754-00VF05GRR 3K units Tape & Reel 4.35V SOT-23-5 FC5754-4DVF05GRR 3K units Tape & Reel
  1. 11. 04 3/19Revision No : 0 4.2V E-SOP-8 FC5754-00SG08NRR 3K units Tape & Reel
  1. 11. 04 4/21Revision No : 0 Pin Functions Name E-SOP-8 SOT-23-5 Function NC 1,6,8 NA Not connected. PROG 2 5 Charge Current Program, Charge Current Monitor and Shutdown Pin. The charge current is programmed by connecting a 1%resistor, RPROG, to ground. When charging in constant-current mode, this pin servos to 1V. In a ll modes, the volt age on this pin can be used to measure the charge current using the following formula: IBAT=(VPROG/RPROG)*960 The PROG pin can also be used to shut down the charger. Disconnecting the program resistor from ground allows a 0.4υA current to pull the PROG pin high. When it reaches the 1.18V shutdown threshold voltage, the charger enters shutdown mode. This pin is also clamped to approximately 2.4V. Reconnecting R PROG to ground will return the charger to normal operation. C onnecting the PROG pin to a voltage between 0.2V and 0.4V can force FC5754 into LDO mode. The PROG pin must not be directly shorted to ground at any condition. GND 3 2 Ground VIN 4 4 Positive Input S upply Voltage. Provides power to the char ger. VIN can range from VBAT+0.5V to 5.5V and should be bypassed with at least a 1 υF capacitor. When VIN drops to within 30mV above the BAT pin voltage, the FC5754 ente rs shutdown mode, dropping IBAT to less than 1υA. BAT 5 3 Charge Current Output and battery volt age feedback. This pin provides charge current to the battery and regulates the final float voltage to 4.2V/4.35V. An internal precision resistor divider from this pin sets the float voltage which is disconnected in standby, shutdown and sleep modes. CHGB 7 1 Open-Drain Charge Status Output. An internal N-channel MOSFET connects CHGB pin to ground when the battery is charging. After the charge cycle is completed, the internal N-channel MOSFET is replaced by a weak pu ll-down of approximately 24 υA, indicating an “AC present” co ndition. When the FC5754 detects an under voltage lockout condition, CHGB is forced high impedance. GND 9 NA Thermal ground area.
  1. 11. 04 5/19Revision No : 0 Absolute Maximum Ratings (Notes 1, 2) VIN, V B A T, V C H G B -0.3V to 6.0V VPROG (N ote 3) -0.3V to VIN +0.3V BAT Short-Circuit Duration Continuous BAT Pin Current 1A PROG Pin Current 1mA Storage Temperature Range -65°C to160°C Junction Temperature (TJ) 150°C Lead Temperature (10 sec.) 260°C Thermal Resistance (JA) SOT-23-5 (Note 5) E-SOP-8L 75°C/W Operating Ratings Temperature Range - 40°C to 85°C Supply Voltage VBAT+0.5V to 5.5V Note: Devices are ESD sensitive. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the device.

Electrical Characteristics

Unless otherwise specified, TA=25°C and VIN=5V. Symbol Parameter Conditions Min Typ Max Units VBAT 5 . 5 5 2 . 4 V 2 . 4 = VIN Input Volta ge VBAT 5 . 5 4 . 4 V 5 3 . 4 = V Charge Mode, RPROG=10K (Note 4) 150 260 330 ㎂ Standby Mode (Charge Terminated) 50 106 150 ICC Input Supply Current Shutdown Mode (RPROG Not Connected, VIN<VBAT or VIN <VUV) 20 45 75 0°C ≦ T A ≦ 85°C (V FLOAT=4.2V) 4. 158 4.2 4. 242 V VFLOAT Regulated Output (Float) Voltage 0°C ≦ T A ≦ 85°C (V FLOAT=4.35V) 4. 3065 4. 35 4. 3935 V RPROG=2K, Current Mode 447 480 513 mA Standby Mode, VBAT=4.2V -1 0 1 Shutdown Mode (RPROG Not Connected) -1 0 1 IBAT BAT Pin Current Sleep Mode, VIN=0V -1 0 1 ITRICKLE Trickle Charge Current V BAT<VTRICKLE, RPROG=2K 21 50 75 mA VTRICKLE Trickle Charge Threshold Voltage RPROG=10K, VBAT Rising 2.8 2.9 3.0 V VTRHYS Trickle Charge Hysteresis Voltage RPROG V m 0 1 2 K 0 1 = VUV VIN Under voltage Lockout Threshold From VIN Low to High 2.45 3.0 3. 75 V VUVHYS VIN Under voltage Lockout Hysteresis V m 0 8 1 V 5 2 . 1 8 1 . 1 g n i s i R n i P G O R P VMSD Manual Shutdown Threshold Voltage V 4 0 . 1 0 0 . 1 g n i l l a F n i P G O R P VIN from Low to High 80 140 mV VASD VIN-VBAT Lockout Threshold Voltage VIN from High to Low 5 30 mV

  1. 11. 04 6/19Revision No : 0 ITERM C/10 Termination Current Threshold RPROG A m / A m 1 . 0 K 0 1 = VPROG PROG Pin Voltage RPROG=10K, Current Mode 0.93 1.0 1. 07 V ICHGB CHGB Pin Weak Pull-Down Current VCHGB 4 2 V 5 = ㎂ VCHGB CHGB Pin Output Low Voltage I CHGB V 6 . 0 3 2 . 0 A m 5 = VRECHRG Recharge Battery Threshold Voltage VFLOAT-VRECHRG V m 0 6 1 TILM Junction Temperature in Constant Temperature Mode 0 2 1 oC RON m 0 5 5 e c n a t s i s e R ” N O “ T E F r e w o P Ω TSS Soft-Start Time IBAT=0 to IBAT=960V/RPROG 100 ㎲ TRECHARGE Recharge Comparator Filter Time VBAT s m 5 . 4 4 . 2 5 7 . 0 w o L o t h g i H TTERM Termination Comparator Filter Time IBAT Falling Below ICHG/10 0.4 1.1 2.5 ms IPROG 4 . 0 t n e r r u C p u - l l u P n i P G O R P Note 1: Absolute Maximum ratings indicate limits beyond which damage may occur. Electrical specifications are not applicable when the device is operated outside of its rated operating conditions. Note 2: All voltages are defined and measured with respect to the potential at the ground pin. Note 3: Can not exceed 6.0V. Note 4: Supply current includes PROG pin current (approximately 100㎂) but does not include any current delivered to the battery through the BAT pin (approximately 96mA). Note 5: 80oC/W to150oC/W, depending on PCB Layout.
  1. 11. 04 7/19Revision No : 0 Functional Block Diagram State Diagram
  1. 11. 04 8/19Revision No : 0 Typical Applications USB/Wall Adapter Power Li-ion Charger Full Featured Single Cell Li-ion Charger Li-ion Charger with External Power Dissipation Basic Li-ion Charger with Reverse Polarity Input Protection Turn off the LED after Charge is Terminated *The formula for R1 is A VR υ35 11＜ , where V1 is the turn-on threshold voltage of the LED device.
  1. 11. 04 9/19Revision No : 0 Typical Performance Characteristics Unless otherwise specified, VIN = 5V, TA = 25°C.
  1. 11. 04 10/19Revision No : 0 Typical Performance Characteristics Unless otherwise specified, VIN = 5V, TA = 25°C. (Continued)
  1. 11. 04 11/19Revision No : 0 Typical Performance Characteristics Unless otherwise specified, VIN = 5V, TA = 25°C. (Continued)
  1. 11. 04 12/19Revision No : 0 Typical Performance Characteristics Unless otherwise specified, VIN = 5V, TA = 25°C. (Continued)
  1. 11. 04 13/19Revision No : 0 Typical Performance Characteristics Unless otherwise specified, VIN = 5V, TA = 25°C. Charge Current vs. Battery Voltage 200 400 600 800 1000 1200 VBAT (V) IBAT (mA) SOT-23-5 E-SOP-8L VIN=5V RPROG=910KΩ Thermal Regulation Charger Current vs. Input Voltage 200 400 600 800 1000 1200 4.0 4.3 4 6 4.9 5 2 5.5 VIN (V) IBAT (mA) SOT-23-5 E-SOP-8L VBAT=4V RPROG=910KΩ Thermal Regulation
  1. 11. 04 14/19Revision No : 0 Operation The FC5754 is a single cell lithium-ion battery charger using a constant-current/constant-voltage algorithm. It can deliver up to 1A of charge current (using a good thermal PCB layout) wi th a final float voltage accuracy of ±1%. The FC5754 includes an inte rnal P-channel power MOSFET and thermal regulation circuitry. No blocking diode or exte rnal current sense re sistor is required; th us, the basic charger circuit re quires only two external components. Furthermore, the FC5754 is capable of operating from a USB power source. Normal Charge Cycle A charge cycle begins when the voltage at the VIN pin rises above the UVLO threshold level and a 1% program resistor is connected from the PROG pin to ground or when a battery is connected to the charger output. If the BAT pin is less than 2.9V, the charger ente rs trickle charge mode. In this mode, the FC 5754 su pplies approximately 1/10 the programmed charge current to bring the ba ttery volta ge up to a safe level for full current charging. When the BAT pin voltage rises above 2.9V, the charger enters constant-current mode, where the p rogrammed charge cu rrent is su pplied to the batt ery. When the BAT pin approaches the final float voltage (4.2V), the FC5754 enters constant-voltage mode and the charge current begins to decrease. When the charge current drops to 1/10 of the programmed value, the charge cycle ends. Programming Charge Current The charge current is programmed using a single resistor from the PROG pin to ground. The battery charge current is 960 times the current out of the PROG pin. The program resistor and the charge current are calculated using the following equations: PROG CHG CHG PROG R VII VR 960,960 == The charge cu rrent out of the BAT pin can be determined at any time by monitoring the PROG pin voltage using the following equation: 960∗ = PROG PROG BAT R VI Charge Termination A charge cycle is terminated when the charge current falls to 1/10th 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 100mV for longer than T TERM (typically 1. 1ms), charging is terminated. The charge current is latched off and the FC5754 enters standby mode, where the input supply current drops to 106 uA. (N ote: C/10 te rmination is disabled in trickle charging and thermal limiting modes). The FC5754 draws no current from the battery in standby mode . This feature reduces the charge and discharge cycles on the ba ttery, further prolonging the battery life. Any external source (V PROG) that holds the PROG pin above 100mV wi ll prevent the FC5754 from terminating a charge cycle. However, if the PROG pin is controlled by external source, current sourcing from the BAT pin can be infinity (until the internal power MOSFET is burned out or the BAT pin voltage is close to its final float voltage), and the formula for charge current is not valid anymore. Therefor e, cont rolling the PROG pin by external so urce below 1.1V should be avoided when a battery is connected to BAT pin. However, with no battery present, forcing V PROG to 0.2V~0.4V enables FC5754 to act as a LDO (LDO mode). In the LDO mode, load current at the BAT pin is recommended to be below 150mA to avoid overheating. When charging, transient loads on the BAT pin can cause the PR OG pin to fall below 100mV for short periods of time before the DC char ge current has dropped to 1/10th the programmed value. The 1.1ms filter time (TTERM) on the termination comparator ensures that tr ansient loads of this nat ure do not re sult in premature charge cycle termination. Once the average charge current drops below 1/ 10th the programmed value, the FC5754 te rminates the charge cycle and ceases to provide any current through the BAT pin. This is the standby mode, and all loads on the BAT pin must be supplied by the battery. In the standby mode, any signal below the manual shutdown threshold voltage (typically 1.18V) on the PROG pin is transparent to FC5754. The FC5754 constantly monitors the BAT pin voltage in standby mode. If this volt age drops below the 4.05V recharge threshold (V RECHRG), another charge cycle begins and current is once again supplied to the battery. To manually restart a charge cycle when in standby mode, the input voltage must be removed and reapplied, or the charger m ust be shut down a nd restarted using the PROG pin. Charge Status Indicator (CHGB) The charge status output has three different states: strong pull-down (~10mA), weak pull-down (~24υA) and high impedance. The strong pull-down state indicates that the FC5754 is in a ch a rge cycle. Once the charge cycle has ter minated, the pin state is determined by undervoltage lockout conditions. A weak pull-down in dicates that VIN meets the U VLO conditions and the FC5754 is re ady to charge. High impedance indicates that the FC5754 is in undervoltage lockout mode: either VIN is le ss than 80mV above the BAT pin volt age or insufficient voltage is applied to the VIN pin. A microprocessor can be used to distinguish between these three states—this meth od is discussed in the Applications Information section. Thermal Limiting An internal the rma l feedback loop reduces the programmed charge current if the die te mperature attempts to rise above a preset value of approximately 120°C. This feature protects the FC5754 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 FC5754. The charge current can be set according to typical (not worst-case) ambient temperature wi th the a ssurance that the charger will automatically reduce the current in worst-case conditions. SOT power considerations are
  1. 11. 04 15/19Revision No : 0 discussed further in the Applications Information section. Undervoltage Lockout (UVLO) An internal undervoltage lockout circuit monitors the input voltage and keeps the charger in shutdown mode until VIN rises above the undervoltage lockout threshold. The U VLO ci rcuit h as a built -in h ysteresis of 200mV. Furthermore, to protect against reverse current in the power MOSFET, the UVLO circuit keeps the charger in shutdown mode if VIN falls to within 30mV of the battery voltage. If the UVLO comparator is tripped, the charger will not come out of shutdown mode until VIN ris es 80mV above the battery voltage. Manual Shutdown At any point in the charge cycle, the FC5754 can be put into shutdown mode by removing RPROG thus floating the PROG pin. This reduces the battery drain current to about to 0υA and the supply current to less than 45υA. A new charge cycle can be initiated by reconnecting the program resistor. In manual shutdown, the CHGB pin is in a weak pull-down state as long as VIN is high enough to exceed the UVLO conditions. The CHGB pin is in a hi gh impedance state if the FC57754 is in und ervoltage lockout mode: either VIN is within 80mV of the BAT pin voltage or insufficient voltage is applied to the VIN pin. Automatic Recharge Once the charge cycle is terminated, the FC5754 continuously monitors the voltage on the BAT pin using a comparator with a 2ms filter time (T RECHARGE). A charge cycle restarts wh en the ba ttery volt age falls below 4.05V (which corresponds to a pproximately 80% to 90% battery capacity). This ensures that the battery is kept at or ne ar a fully charged condition and elim inates the need for periodic charge cycle ini tiations. CHGB output enters a strong pulldown state during recharge cycles.

Application Information

The constant-voltage mode fee dback loop is st able 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. Wh en using high value, low ESR ceramic capacitors, it is recommended to add a 1 Ω resistor in series with the capacitor. No series re sistor is needed if tantalum capacitor s are used. In constant-current mode, the PROG pin is in the feedback loop, not the battery. The constant-current mode st ability is affected by the impedance at the PROG pin. With no additional capacitance on the PROG pin, the charger is st able with program re sistor values as high as 100k. However, additi onal capacitance on this node reduces the maximum allowed p rogram re sistor. The pole frequency at the PROG pin should be kept above 100kHz. Theref ore, if the PROG pin is loaded with a capacitance, CPROG, the following equation can be used to calculate th e ma ximum resistance value for RPROG: PROG PROG C R ∗ ∗ = 510 2 Average, rather than instantaneous, char ge current may be of in terest to the user. For example, if a switching power supply operating in low current mode is connected in parallel with the battery, the average current be ing pulled out of the BAT pin is typically of more interest than the instantaneous current pulses. In such a case, a simple RC fi lter can be used on the PROG pin to meas ure the av erage battery current as shown in Figure 1. A 10㎑ re sistor h as been added between the PROG pin and th e fi lter capacitor to ensure stability. Power Dissipation The conditions that cause the FC5754 to redu ce charge current through thermal feedback can be approximated by considering the power dissipated in the IC. Ne arly all of this power dissipation is generated by the i nternal M OSFET—this is calculated to be approximately: PD = (VIN – VBAT) • IBAT where PD is the power dissipated, VIN is the input supply voltage, VBAT is the battery voltage and IBAT is the charge current. The a pproximate a mbient temperature at which the thermal feedback begins to protect the IC is: TA = 120oC – PDθJA TA = 120 oC – (VIN – VBAT) • IBAT • JA Example: An FC5754 operating from a 5V USB supply is programmed to supply 500mA full -scale current to a discharged Li-Ion ba ttery with a volt age of 3.7V. Assuming JA is 100oC/W, the a mbient temperature at which the FC5754 w ill b egin to re duce the charge current is approximately: TA = 120 oC – (5V – 3.7V) • (500mA) •100oC/W TA = 120 oC – 0.65W •100oC/W = 120 oC – 65 oC TA = 55 oC The F C5754 can be used above 55 oC ambient, but the charge curren t wil l be reduced from 500mA. The Figure 1. Isolating Capacitive load on PROG Pin and Filtering

(especially the ground lead) to the PC board copper. component, such as a r esistor or diode. to a discharged Li-Ion battery with a voltage of 3.7V. Solving for IBAT using the quadratic formula. connecting the charger input to a live power source. capacitor will minimize start-up voltage transients. Figure 2. A Circuit to Maximize Thermal Mode Charge Current

  1. 11. 04 18/19Revision No : 0 Package Outline Drawing SOT-23-5 TOP VIEW SIDE VIEW PIN#1 MARK 1 3 5 4 DETAIL A E E1 e D A L 1 3 b DETAIL A c Min. Max. A 0.90 1.45 A1 0.00 0.15 b 0.30 0.50 c 0.08 0.25 D 2.70 3.10 E 1.40 1.80 E1 2.60 3.00 e L 0.30 0.60

0.95 BSC

  1. 11. 04 19/19Revision No : 0 Package Outline Drawing SOP-8 (E) (150 mil) Min Max A 1.35 1.75 Min Max A1 0.00 0.25 D2 1.93 2.39 b 0.33 0.51 E2 1.93 2.39 c 0.17 0.25 D 4.80 5.00 E 3.81 4.00 E1 5.79 6.20 e L 0.41 1.27

1.27 BSC