BQ24004PWPR

bq24004 bq24005 bq24006 www.ti.com SLUS476F – DECEMBER 2000 – REVISED MAY 2012 TWO-CELL Li-ION CHARGE MANAGEMENT IC FOR PDAs AND INTERNET APPLIANCES Check for Samples: bq24004, bq24005, bq24006 FEATURES 1 • 2 • • • • • • • • • • • Highly Integrated Solution With FET Pass Transistor and Reverse-Blocking Schottky and Thermal Protection Integrated Voltage and Current Regulation With Programmable Charge Current High-Accuracy Voltage Regulation (±1%) Ideal for Low-Dropout Linear Charger Designs for Two-Cell Li-Ion Packs With Coke or Graphite Anodes Up to 1.2-A Continuous Charge Current Safety-Charge Timer During Preconditioning and Fast Charge Integrated Cell Conditioning for Reviving Deeply Discharged Cells and Minimizing Heat Dissipation During Initial Stage of Charge Optional Temperature or Input-Power Monitoring Before and During Charge Various Charge-Status Output Options for Driving Single, Double, or Bicolor LEDs or Host-Processor Interface Charge Termination by Minimum Current and Time Low-Power Sleep Mode Packaging: 20-Lead TSSOP PowerPAD™ APPLICATIONS • • • • PDAs Internet Appliances MP3 Players Digital Cameras DESCRIPTION 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. The bq2400x measures battery temperature using an external thermistor. For safety, 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 lowcurrent precharge to condition the battery. A preconditioning timer provides additional safety. Following pre- conditioning, 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. 1 2 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. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright © 2000–2012, Texas Instruments Incorporated bq24004 bq24005 bq24006 SLUS476F – DECEMBER 2000 – REVISED MAY 2012 www.ti.com 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) (2) bq24004PWP –40°C to 125°C (1) (2) Single LED bq24005PWP 2 LEDs bq24006PWP Single bicolor LED The PWP package is available taped and reeled. Add R suffix to device type (e.g., bq24005PWPR) to order. Quantities 2500 devices per reel. For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI Web site at www.ti.com. PACKAGE DISSIPATION RATINGS (1) PACKAGE ΘJA ΘJC TA ≤ 25°C POWER RATING DERATING FACTOR ABOVE TA = 25°C PWP (1) 30.88°C/W 1.19°C/W 3.238 W 0.0324 W/°C 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. ABSOLUTE MAXIMUM RATINGS over operating free-air temperature range unless otherwise noted (1) bq24004 bq24005 bq24006 Supply voltage (VCC with respect to GND) 13.5 V Input voltage (IN, ISNS, 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 TA Operating free-air temperature range –40°C to 70°C Tstg Storage temperature range –65°C to 150°C TJ Junction temperature range –40°C to 125°C Lead temperature (Soldering, 10 s) (1) 300°C 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 UNIT VCC Supply voltage 8.4 10 V VIN Input voltage 8.4 10 V 1.2 A 125 °C Continuous output current TJ 2 Operating junction temperature range Submit Documentation Feedback –40 Copyright © 2000–2012, Texas Instruments Incorporated Product Folder Link(s): bq24004 bq24005 bq24006 bq24004 bq24005 bq24006 www.ti.com SLUS476F – DECEMBER 2000 – REVISED MAY 2012 ELECTRICAL CHARACTERISTICS over recommended operating junction temperature supply and input voltages, and VI (VCC) ≥ VI (IN) ( unless otherwise noted) PARAMETER TEST CONDITIONS MIN TYP EN ≤ V(IHEN) MAX VCC current VCC > VCC_UVLO, VCC current, standby mode EN ≤ V(ILEN) 1 IN current, standby mode EN ≤ V(ILEN) Standby current (sum of currents into OUT and VSENSE pins) VCC < VCC_UVLO, VO(OUT) = 8.6 V, VSENSE = 8.6 V 2 8 EN ≤ V(ILEN), VO(OUT) = 8.6 V, VSENSE = 8.6 V 2 8 1 UNIT mA µA 10 µA µA VOLTAGE REGULATION, 0°C ≤ TJ ≤ 125°C Output voltage VSEL = VSS, 0 < IO ≤ 1.2 A 8.118 8.20 8.282 VSEL = VCC, 0 < IO ≤ 1.2 A 8.316 8.40 8.484 Load regulation 1 mA ≤ IO≤ 1.2 A,VCC = 10 V, VI(IN)= 5 V,TJ = 25°C Line regulation VO(OUT) + VDO + V(ilim)MAX < VI(VCC) < 10 V, TJ = 25°C Dropout voltage = VI(IN)-Vout IO = 1.2 A, VO(OUT) + V(DO) + V(ilim)MAX < VI(VCC) < 10 V V 1 mV 0.01 %/V 0.5 V 0.107 V CURRENT REGULATION, 0°C ≤ TJ ≤ 125°C Current regulation threshold, VI(limit) VSENSE < VO(VSEL-LOW/HIGH) Delay time VSENSE pulsed above V(LOWV) to IO = 10% of regulated value (1) Rise time IO increasing from 10% to 90% of regulated value, R(SNS) ≥ 0.2 Ω (1) 0.093 0.1 1 ms 0.1 1 ms 0.083 1 Ω 60 80 mA V CURRENT SENSE RESISTOR, 0°C ≤ TJ ≤ 125°C External current sense resistor range R(SNS) 100 mA ≤ (ilim) ≤ 1.2 A PRECHARGE CURRENT REGULATION, 0°C ≤ TJ ≤ 125°C Precharge current regulation VSENSE V(OVERV)? No Regulate Current or Voltage Indicate Charge No V I(VSENSE) < V(LOWV)? Yes VI(VSENSE) > V(OVERV)? Yes 22.5 min Timer Expired? No No Yes Yes Charge Timer Expired? No Fault Condition Yes Indicate Fault V I(VSENSE) < V(LOWV)? No Taper Detected? Start 22.5 min Timer Yes POR? or APG/THERM toggle? or EN toggle? No Indicate DONE Yes No 22.5 min T imer Expired? Yes Turn Off Charge Indicate DONE VI(VSENSE) < V(HIGHV)? or POR? or APG/THERM Toggle? or EN Toggle? No Yes Figure 15. Operational Flow Chart 12 Submit Documentation Feedback Copyright © 2000–2012, Texas Instruments Incorporated Product Folder Link(s): bq24004 bq24005 bq24006 bq24004 bq24005 bq24006 www.ti.com SLUS476F – DECEMBER 2000 – REVISED MAY 2012 Charge Qualification and Preconditioning The APG/THERM input can also be configured to monitor 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. Refer to the APG/THERM input section for additional details. 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. APG/THERM Input The bq2400x 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 V(TP1) and V(TP2) thresholds to determine if charging is allowed. (See Figure 17.) U1 1 2 3 4 5 6 7 8 9 10 N/C IN N/C OUT IN OUT VCC VSENSE ISNS AGND N/C STAT2 APG/THM STAT1 EN TMR SEL VSEL GND CR N/C 20 19 PACK+ 18 + 17 - 16 PACK- 15 NTC Thermistor 14 13 TEMP 12 Battery Pack C3 0.22 µF 11 bq24005PWP RT1 RT2 Figure 16. Temperature Sensing Circuit Copyright © 2000–2012, Texas Instruments Incorporated Product Folder Link(s): bq24004 bq24005 bq24006 Submit Documentation Feedback 13 bq24004 bq24005 bq24006 SLUS476F – DECEMBER 2000 – REVISED MAY 2012 www.ti.com If the charger designs incorporate a thermistor, the resistor divider RT1 and RT2 is calculated by using the following two equations. First, calculate RT2. V B RH R C RT2 + RH ǒ V V B H Ǔ ƪ 1 V C 1 * * 1 * RC ǒ V V ƫ V H B C Ǔ * 1 then use the resistor value to find RT1. V V RT1 + B C 1 RT2 * 1 ) 1 R C Where: VB = VCR (bias voltage) RH = Resistance of the thermistor at the desired hot trip threshold 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 bq24005PWP 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. Figure 17. Temperature Threshold 14 Submit Documentation Feedback Copyright © 2000–2012, Texas Instruments Incorporated Product Folder Link(s): bq24004 bq24005 bq24006 bq24004 bq24005 bq24006 www.ti.com SLUS476F – DECEMBER 2000 – REVISED MAY 2012 U1 VCC 1 R(SNS) 2 DC+ C1 10 µF + VCC 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 EN TMR SEL VSEL CR GND N/C 20 19 18 17 16 15 14 13 12 11 bq24005PWP Figure 19. Current Sensing Circuit Charge current feedback, applied through pin ISNS, maintains regulation around a threshold of Vilim. The following formula calculates the value of the sense resistor: V(ilim) R (SNS) + I (REG) 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. where I(REG) 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 (8.2 V) or graphite (8.4 V) anode. Pin VSEL selects the charge regulation voltage. VSEL STATE (see Note) CHARGE REGULATION VOLTAGE Low 8.2 V High 8.4 V 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 TMRSEL STATE CHARGE TIME Floating(1) 3 hours Low 6 hours High 4.5 hours (1) To improve noise immunity, it is recommended that a minimum of 10 pF capacitor be tied to Vss on a floating pin. 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 The three available options allow the user to configure the charge status display for single LED (bq24004), two individual LEDs (bq24005) or a bicolor LED (bq24006). The output stage is totem pole for the bq24004 and bq24006 and open-drain for the bq24005. The following tables summarize the operation of the three options: Table 1. bq24004 (Single LED) CHARGE STATE STAT1 Precharge ON (LOW) Fast charge ON (LOW) FAULT Flashing (1 Hz, 50% duty cycle) Copyright © 2000–2012, Texas Instruments Incorporated Product Folder Link(s): bq24004 bq24005 bq24006 Submit Documentation Feedback 15 bq24004 bq24005 bq24006 SLUS476F – DECEMBER 2000 – REVISED MAY 2012 www.ti.com Table 1. bq24004 (Single LED) (continued) CHARGE STATE STAT1 Done (>90%) OFF (HIGH) Sleep-mode OFF (HIGH) APG/Therm invalid OFF (HIGH) Thermal shutdown OFF (HIGH) Battery absent OFF (HIGH) Table 2. bq24005 (2 Individual LEDs) (continued) CHARGE STATE OFF(1) If thermistor is used, then the Green LED is off. Table 3. bq24006 (Single Bicolor LED) STAT2 (GREEN) Precharge ON (LOW) OFF Fast charge ON (LOW) OFF 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 Done (>90%) OFF (HIGH) ON (LOW) GREEN Sleep-mode OFF (HIGH) OFF (HIGH) OFF APG/Therminvalid OFF (HIGH) OFF (HIGH) OFF Flashing (1 Hz,50% duty cycle) OFF Done (>90%) OFF ON (LOW) Sleep-mode OFF OFF Battery absent APG/Therm invalid OFF OFF (1) Thermal shutdown OFF OFF FAULT OFF (1) Table 2. bq24005 (2 Individual LEDs) STAT1 (RED) STAT2 (GREEN) Battery absent CHARGE STATE CHARGE STATE STAT1 (RED) Thermal shutdown OFF (HIGH) OFF (HIGH) OFF (HIGH) OFF OFF (HIGH)(1) OFF(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. 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 ENABLE (EN) The logic EN input is used to enable or disable the IC. A high-level signal on this pin enables the bq2400x. A low-level signal disables the IC and places the device in a low-power standby mode. 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). 16 Submit Documentation Feedback Copyright © 2000–2012, Texas Instruments Incorporated Product Folder Link(s): bq24004 bq24005 bq24006 bq24004 bq24005 bq24006 www.ti.com SLUS476F – DECEMBER 2000 – REVISED MAY 2012 THERMAL INFORMATION THERMALLY ENHANCED TSSOP-20 DIE The thermally enhanced PWP package is based on the 20-pin TSSOP, but includes a thermal pad (seeFigure 20) to provide an effective thermal contact between the IC and the PWB. Side View (a) DIE 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 (