BQ24007RGWR


 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004                              FEATURES DESCRIPTION D Highly Integrated Solution With FET Pass The bq2400x series ICs are advanced Li-Ion linear charge management devices for highly integrated and space-limited applications. They combine highaccuracy current and voltage regulation; FET passtransistor and reverse-blocking Schottky; battery conditioning, temperature, or input-power monitoring; charge termination; charge-status indication; and charge timer in a small package. Transistor and Reverse-Blocking Schottky and Thermal Protection D Timer-Enable Function That Allows Host to Disable Charge Timer and Termination When Charge Current Is Shared With a Load or When Battery Is Absent D Integrated Voltage and Current Regulation With Programmable Charge Current D High-Accuracy Voltage Regulation (±1%) D Ideal for Low-Dropout Linear Charger Designs for Single-Cell Li-Ion Packs With Coke or Graphite Anodes D Up to 1.2-A Continuous Charge Current D Safety-Charge Timer During Preconditioning and Fast Charge D Integrated Cell Conditioning for Reviving Deeply Discharged Cells and Minimizing Heat Dissipation During Initial Stage of Charge D Optional Temperature or Input-Power Monitoring Before and During Charge D Various Charge-Status Output Options for Driving Single, Double, or Bicolor LEDs or Host-Processor Interface D Charge Termination by Minimum Current and Time D Low-Power Sleep Mode D Packaging: 5 mm × 5 mm MLP (bq24007)or 20-Lead TSSOP PowerPAD APPLICATIONS D D D D PDAs Internet Appliances MP3 Players Digital Cameras The bq24007 and bq24008 provide the timer-enable function, allowing the host to disable the charge timer when charge current is shared with a load or when the battery is absent. This feature is ideal for applications such as cellular phones, PDAs, and internet appliances. The bq2400x measures battery temperature using an external thermistor. For safety reasons, the bq2400x inhibits charge until the battery temperature is within the user-defined thresholds. Alternatively, the user can monitor the input voltage to qualify charge. The bq2400x series then charge the battery in three phases: preconditioning, constant current, and constant voltage. If the battery voltage is below the internal low-voltage threshold, the bq2400x uses low-current precharge to condition the battery. A preconditioning timer provides additional safety. Following preconditioning, the bq2400x applies a constant-charge current to the battery. An external sense-resistor sets the magnitude of the current. The constant-current phase is maintained until the battery reaches the charge-regulation voltage. The bq2400x then transitions to the constant voltage phase. The user can configure the device for cells with either coke or graphite anodes. The accuracy of the voltage regulation is better than ±1% over the operating junction temperature and supply voltage range. Charge is terminated by maximum time or minimum taper current detection The bq2400x automatically restarts the charge if the battery voltage falls below an internal recharge threshold. Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. PowerPAD is a trademark of Texas Instruments.    !"#$%!  &'""(% $ ! )'
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 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. ORDERING INFORMATION PACKAGE TJ CHARGE STATUS CONFIGURATION 20-LEAD HTTSOP PowerPAD (PWP)(1) 20-LEAD 5 mm × 5 mm MLP (RGW)(2) bq24007PWP bq24007RGW Single LED bq24008PWP Not available Single bicolor LED −40°C to 125°C (1) The PWP package is available taped and reeled. Add R suffix to device type (e.g. bq24007PWPR) to order. Quantities 2500 devices per reel. (2) The RGW package is available taped and reeled. Add R suffix to device type (e.g. bq24007RGWR) to order. Quantities 3000 devices per reel. PACKAGE DISSIPATION RATINGS PACKAGE ΘJA ΘJC TA ≤ 25°C POWER RATING PWP(1) RGW(2) 30.88°C/W 1.19°C/W 3.238 W 31.41°C/W 1.25°C/W DERATING FACTOR ABOVE TA = 25°C 0.0324W/°C 3.183 W 0.0318W/°C (1) This data is based on using the JEDEC high-K board and topside traces, top and bottom thermal pad (6,5 × 3,4 mm), internal 1 oz power and ground planes, 8 thermal via underneath the die connecting to ground plane. (2) This data is based on using the JEDEC high-K board and topside traces, top and bottom thermal pad (3,25 × 3,25 mm), internal 1 oz power and ground planes, 9 thermal via underneath the die connecting to ground plane. ABSOLUTE MAXIMUM RATINGS over operating free-air temperature range unless otherwise noted(1) bq24007 bq24008 Supply voltage (VCC with respect to GND) 13.5 V Input voltage (IN, ISNS, TMR EN, APG/THERM/CR/STAT1/STAT2, VSENSE, TMR SEL, VSEL) (all with respect to GND) 13.5 V Output current (OUT pins) 2A Output sink/source current (STAT1 and STAT2) 10 mA Operating free-air temperature range, TA −40°C to 70°C Storage temperature range, Tstg −65°C to 150°C Junction temperature range, TJ −40°C to 125°C Lead temperature (Soldering, 10 s) 300°C (1) Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS MIN MAX Supply voltage, VCC 4.5 10 V Input voltage, VIN 4.5 10 V Continuous output current Operating junction temperature range, TJ 2 −40 UNIT 1.2 A 125 °C 

 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 ELECTRICAL CHARACTERISTICS over recommended operating junction temperature supply and input voltages, and VI (VCC) ≥ VI (IN) ( unless otherwise noted) PARAMETER VCC current Standby current (sum of currents into OUT and VSENSE pins) TEST CONDITIONS MIN TYP VCC > VCC_UVLO VCC < VCC_UVLO, VO(OUT) = 4.3 V, VSENSE = 4.3 V 2 MAX UNIT 1 mA 4 µA VOLTAGE REGULATION, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS 0 < IO ≤ 1.2 A VSEL = VSS, Output voltage 0 < IO ≤ 1.2 A 1 mA ≤ IO ≤ 1.2 A, VI(IN)= 5 V, VCC =5 V, TJ = 25°C VO(OUT)+VDO+Vilim(MAX) < VI(VCC) < 10 V, VSEL = VCC, Load regulation Line regulation Dropout voltage = VI(IN)-VO(OUT) IO = 1.0 A, IO = 1.2 A, MIN TYP MAX UNIT 4.059 4.10 4.141 V 4.158 4.20 4.242 V TJ = 25°C 1 mV 0.01 %/V 4.9 V V(OVERV)? Indicate Charge No No VI(VSENSE) > V(OVERV)? Yes No Yes VI(VSENSE) < V(LOWV)? No VI(VSENSE) < V(LOWV)? Yes 22.5 min Timer Expired? No Yes Fault Condition Indicate Fault POR? or APG/THERM Toggle? No Yes Figure 15. Operational Flow Chart With the Charge Timers Disabled (TMR EN = 1) Charge Qualification and Preconditioning The bq2400x starts a charge cycle when power is applied while a battery is present. Charge qualification is based on battery voltage and the APG/THERM input. As shown in the block diagram, the internal LowV comparator output prevents fast-charging a deeply depleted battery. When set, charging current is provided by a dedicated precharge current source. The precharge timer limits the precharge duration. The precharge current also minimizes heat dissipation in the pass element during the initial stage of charge. The APG/THERM input can also be configured to monitor 14 either the adapter power or the battery temperature using a thermistor. The bq2400x suspends charge if this input is outside the limits set by the user. Please refer to the APG/THERM input section for additional details. Timer Enable Function The logic TRM EN enables or disables the charge safety timer. A low-level signal on this pin enables the timer (charge and taper). A high-level input disables the timers and allows the charger to operate continuously. No charge termination is provided when this input is high. Note that the preconditioning timer remains active regardless of the status of this input. The TRM EN input can be changed any time during the charge cycle. A low-to-high transition on this pin resets the timers. 

 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 APG/THERM Input The bq400x continuously monitors temperature or system input voltage by measuring the voltage between the APG/THERM (adapter power good/thermistor) and GND. For temperature, a negative- or a positive- temperature coefficient thermistor (NTC, PTC) and an external voltage divider typically develop this voltage. (See Figure 16.) The bq2400x compares this voltage against its internal VTP1 and VTP2 thresholds to determine if charging is allowed. (See Figure 17.) U1 1 N/C 2 IN 3 5 6 7 8 19 OUT IN 4 20 N/C OUT VCC VSENSE ISNS AGND N/C STAT2 APG/THM STAT1 VSEL 10 − 16 PACK− 15 NTC Thermistor 14 13 TEMP 12 CR GND + 17 TMR EN TMR SEL 9 PACK+ 18 Battery Pack C3 0.22 µF 11 N/C bq24008PWP RT1 RT2 Figure 16. Temperature Sensing Circuit If the charger designs incorporate a thermistor, the resistor divider RT1 and RT2 is calculated by using the following two equations. Where: First, calculate RT2. RH = Resistance of the thermistor at the desired hot trip threshold V B RH R C RT2 + RH ǒ V V B H Ǔ ƪ 1 V C * * 1 * RC ǒ V V then use the resistor value to find RT1. V RT1 + V B C 1 RT2 * 1 ) 1 R C 1 ƫ V H B C Ǔ * 1 VB = VCR (bias voltage) RC = Resistance of the thermistor at the desired cold trip threshold VH = VP2 or the lower APG trip threshold VC = VP2 or the upper APG trip threshold RT1 = Top resistor in the divider string RT2 = Bottom resistor in the divider string 15 

 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 U1 VCC 1 2 DC+ 3 VCC 4 Temp Fault 5 6 R1 VTP1 7 Normal Temp Range VTP2 8 R2 9 Temp Fault 10 DC− N/C N/C IN OUT IN OUT VCC VSENSE ISNS AGND N/C STAT2 APG/THM STAT1 TMR EN TMR SEL VSEL CR GND N/C 20 19 18 17 16 15 14 13 12 11 GND bq24008PWP Figure 17. Temperature Threshold Figure 18. APG Sensing Circuit Values of resistors R1 and R2 can be calculated using the following equation: R2 V (APG) + VCC (R1 ) R2) where V(APG) is the voltage at the APG/THM pin. Current Regulation The bq2400x provides current regulation while the battery-pack voltage is less than the regulation voltage. The current regulation loop effectively amplifies the error between a reference signal, Vilim, and the drop across the external sense resistor, RSNS. U1 VCC 1 R(SNS) DC+ C1 10 µF + VCC 2 3 4 DC− 5 6 C2 0.1 µF 7 8 9 10 N/C N/C IN OUT IN OUT VCC VSENSE ISNS AGND N/C STAT2 APG/THM STAT1 TMR EN TMR SEL VSEL CR GND N/C bq24008PWP Figure 19. Current Sensing Circuit 16 20 19 18 17 16 15 14 13 12 11 

 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 Charge current feedback, applied through pin ISNS, maintains regulation around a threshold of Vilim. The following formula calculates the value of the sense resistor: R (SNS) + V(ilim) Minimum Current: The bq2400x monitors the charging current during the voltage regulation phase. The bq2400x initiates a 22-minute timer once the current falls below the taperdet trip threshold. Fast charge is terminated once the 22-minute timer expires. Charge Status Display I (REG) where IREG is the desired charging current. Voltage Monitoring and Regulation Voltage regulation feedback is through pin VSENSE. This input is tied directly to the positive side of the battery pack. The bq2400x supports cells with either coke (4.1 V) or graphite (4.2 V) anode. Pin VSEL selects the charge regulation voltage. The two available options allow the user to configure the charge status display for single LED (bq24007) or a bicolor LED (bq24008). The output stage is totem pole for the bq24007 and bq24008. The following tables summarize the operation of the three options: Table 1. bq24007 (Single LED) CHARGE STATE STAT1 Precharge ON (LOW) Fast charge ON (LOW) VSEL State (see Note) CHARGE REGULATION VOLTAGE Low 4.1 V Done (>90%) OFF (HIGH) High 4.2 V Sleep-mode OFF (HIGH) APG/Therm invalid OFF (HIGH) Thermal shutdown OFF (HIGH) Battery absent OFF (HIGH) NOTE: VSEL should not be left floating. Charge Termination The bq2400x continues with the charge cycle until termination by one of the two possible termination conditions: Maximum Charge Time: The bq2400x sets the maximum charge time through pin TMRSEL. The TMR SEL pin allows the user to select between three different total charge-time timers (3, 4, 5, or 6 hours). The charge timer is initiated after the preconditioning phase of the charge and is reset at the beginning of a new charge cycle. Note that in the case of a fault condition, such as an out-of-range signal on the APG/THERM input or a thermal shutdown, the bq2400x suspends the timer. Charge timers are active only when TMR EN input is low. TMRSEL STATE Floating(1) CHARGE TIME Low 6 hours High 4.5 hours 3 hours (1) To improve noise immunity, it is recommended that a minimum of 10 pF capacitor be tied to Vss on a floating pin. FAULT Flashing (1 Hz, 50% duty cycle) Table 2. bq24008 (Single Bicolor LED) LED1 (RED) LED2 (GREEN) APPARENT COLOR Precharge ON (LOW) OFF (HIGH) RED Fast charge ON (LOW) OFF (HIGH) RED FAULT ON (LOW) ON (LOW) YELLOW CHARGE STATE Done (>90%) OFF (HIGH) ON (LOW) GREEN Sleep-mode OFF (HIGH) OFF (HIGH) OFF APG/Therm invalid OFF (HIGH) OFF (HIGH) OFF Thermal shutdown OFF (HIGH) OFF (HIGH) OFF Battery absent OFF (HIGH) OFF (HIGH)(1) OFF(1) (1) If thermistor is used, then the green LED is off. Thermal Shutdown The bq2400x monitors the junction temperature TJ of the DIE and suspends charging if TJ exceeds 165°C. Charging resumes when TJ falls below 155°C. 17 

 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 DETAILED DESCRIPTION POWER FET VOLTAGE SENSE The integrated transistor is a P-channel MOSFET. The power FET features a reverse-blocking Schottky diode, which prevents current flow from OUT to IN. To achieve maximum voltage regulation accuracy, the bq2400x uses the feedback on the VSENSE pin. Externally, this pin should be connected as close to the battery cell terminals as possible. For additional safety, a 10-kΩ internal pullup resistor is connected between the VSENSE and OUT pins. An internal thermal-sense circuit shuts off the power FET when the junction temperature rises to approximately 165°C. Hysteresis is built into the thermal sense circuit. After the device has cooled approximately 10°C, the power FET turns back on. The power FET continues to cycle off and on until the fault is removed. CURRENT SENSE The bq2400x regulates current by sensing, on the ISNS pin, the voltage drop developed across an external sense resistor. The sense resistor must be placed between the supply voltage (Vcc) and the input of the IC (IN pins). 18 TIMER ENABLE The logic TMR EN enables or disables the charge safety timer. A low-level signal on this pin enables the timers. A high-level input disables the timers and allows the charge to operate continuously. No charge termination is provided when this input is high. Note that the preconditioning timer remains active regardless of the status of this input. 

 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 THERMAL INFORMATION THERMALLY ENHANCED TSSOP-20 DIE The thermally enhanced PWP package is based on the 20-pin TSSOP, but includes a thermal pad (see Figure 20) to provide an effective thermal contact between the IC and the PWB. Traditionally, surface mount and power have been mutually exclusive terms. A variety of scaled-down TO220-type packages have leads formed as gull wings to make them applicable for surface-mount applications. These packages, however, suffer from several shortcomings: they do not address the very low profile requirements (< 2 mm) of many of today’s advanced systems, and they do not offer a pin-count high enough to accommodate increasing integration. On the other hand, traditional low-power surface-mount packages require power-dissipation derating that severely limits the usable range of many high-performance analog circuits. Side View (a) DIE End View (b) Thermal Pad The PWP package (thermally enhanced TSSOP) combines fine-pitch surface-mount technology with thermal performance comparable to much larger power packages. The PWP package is designed to optimize the heat transfer to the PWB. Because of the very small size and limited mass of a TSSOP package, thermal enhancement is achieved by improving the thermal conduction paths that remove heat from the component. The thermal pad is formed using a lead-frame design (patent pending) and manufacturing technique to provide the user with direct connection to the heat-generating IC. When this pad is soldered or otherwise coupled to an external heat dissipator, high power dissipation in the ultrathin, finepitch, surface-mount package can be reliably achieved. Bottom View (c) Figure 20. Views of Thermally Enhanced PWP Package Because the conduction path has been enhanced, power-dissipation capability is determined by the thermal considerations in the PWB design. For example, simply adding a localized copper plane (heat-sink surface), which is coupled to the thermal pad, enables the PWP package to dissipate 2.5 W in free air. (Reference Figure 22(a), 8 cm2 of copper heat sink and natural convection.) Increasing the heat-sink size increases the power dissipation range for the component. The power dissipation limit can be further improved by adding airflow to a PWB/IC assembly. (See Figure 22(b) and 22(c).) The line drawn at 0.3 cm2 in Figures 21 and 22 indicates performance at the minimum recommended heat-sink size. 19 

 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 THERMAL INFORMATION THERMAL RESISTANCE vs COPPER HEAT-SINK AREA 150 Natural Convection R θ JA − Thermal Resistance − ° C/W 125 50 ft/min 100 ft/min 100 150 ft/min 200 ft/min 75 50 250 ft/min 300 ft/min 25 0 0.3 1 2 3 4 5 Copper Heat-Sink Area − cm2 Figure 21 20 6 7 8 

 www.ti.com SLUS479D − JANUARY 2001 − REVISED NOVEMBER 2004 THERMAL INFORMATION 3.5 3.5 TA = 55°C 300 ft/min PD − Power Dissipation Limit − W 3 150 ft/min 2.5 2 Natural Convection 1.5 1 0.5 0 3 300 ft/min 2.5 2 150 ft/min 1.5 Natural Convection 1 0.5 0 0.3 2 4 6 0 8 Copper Heat-Sink Size − cm2 0 0.3 2 4 6 Copper Heat-Sink Size − cm2 (a) 8 (b) 3.5 TA = 105°C 3 PD − Power Dissipation Limit − W PD − Power Dissipation Limit − W TA = 25°C 2.5 2 1.5 150 ft/min 300 ft/min 1 Natural Convection 0.5 0 0 0.3 2 4 6 8 Copper Heat-Sink Size − cm2 (c) Figure 22. Power Ratings of the PWP Package at Ambient Temperatures of 25°C, 55°C, and 105°C 21 IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment. TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and applications using TI components. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards. TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from TI under the patents or other intellectual property of TI. Reproduction of information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for such altered documentation. Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements. Following are URLs where you can obtain information on other Texas Instruments products and application solutions: Products Applications Amplifiers amplifier.ti.com Audio www.ti.com/audio Data Converters dataconverter.ti.com Automotive www.ti.com/automotive DSP dsp.ti.com Broadband www.ti.com/broadband Interface interface.ti.com Digital Control www.ti.com/digitalcontrol Logic logic.ti.com Military www.ti.com/military Power Mgmt power.ti.com Optical Networking www.ti.com/opticalnetwork Microcontrollers microcontroller.ti.com Security www.ti.com/security Telephony www.ti.com/telephony Video & Imaging www.ti.com/video Wireless www.ti.com/wireless Mailing Address: Texas Instruments Post Office Box 655303 Dallas, Texas 75265 Copyright  2004, Texas Instruments Incorporated