bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 SINGLE-CELL Li-ION CHARGE MANAGEMENT IC FOR PDAs AND INTERNET APPLIANCES FEATURES D Highly Integrated Solution With FET Pass Transistor and Reverse-Blocking Schottky and Thermal Protection 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 or 20-Lead TSSOP PowerPAD APPLICATIONS D D D D 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 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 is provided for 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. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright 2002, Texas Instruments Incorporated bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 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 20-LEAD HTTSOP PowerPAD (PWP)(1) 20-LEAD 5 mm × 5 mm MLP (RGW)(2) CHARGE STATUS CONFIGURATION bq24001PWP bq24001RGW Single LED bq24002PWP bq24002RGW 2 LEDs –40°C 40 C to 125°C 125 C bq24003PWP bq24003RGW Single bicolor LED (1) The PWP package is available taped and reeled. Add R suffix to device type (e.g. bq24001PWPR) to order. Quantities 2500 devices per reel. (2) The RGW package is available taped and reeled. Add R suffix to device type (e.g. bq24001RGWR) 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 DERATING FACTOR ABOVE TA = 25°C 0.0324W/°C 31.41°C/W 1.25°C/W 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) bq24001 bq24002 bq24003 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 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 sec) 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 1.2 A –40 125 °C Continuous output current Operating junction temperature range, TJ 2 UNIT bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 ELECTRICAL CHARACTERISTICS over recommended operating junction temperature supply and input voltages, and VI (VCC) ≥ VI (IN) ( unless otherwise noted) PARAMETER TEST CONDITIONS VCC current VCC current, standby mode VCC > VCC_UVLO, EN ≤ VIL(EN) IN current, standby mode EN ≤ VIL(EN) MIN TYP EN ≤ VIH(EN) MAX 1 VOUT = 4.3 V, VOUT = 4.3 V, mA µA 1 10 Standby current (sum of currents into OUT VCC < VCC_UVLO, and VSENSE pins) EN <= VilEN, UNIT VSENSE = 4.3V 2 4 VSENSE = 4.3 V 2 4 µA µA VOLTAGE REGULATION, 0°C ≤ TJ ≤ 125°C PARAMETER Output voltage Load regulation Line regulation Dropout voltage = VI(IN) VI(IN)-Vout Vout MIN TYP MAX UNIT VSEL = VSS, TEST CONDITIONS 0 < IO ≤ 1.2 A 4.059 4.10 4.141 V VSEL = VCC, 0 < IO ≤ 1.2 A 4.158 4.20 4.242 V 1 mA ≤ IO ≤ 1.2 A, VI(IN)= 5 V, VCC =5 V, TJ = 25°C VOUT+VDO+Vilim(MAX) < VI(VCC) < 10 V, IO = 1.0 A, IO = 1.2 A, 1 TJ = 25°C 4.9 V <VI(Vcc)< 10 V mV 0.01 VOUT+VDO+VilimMAX <VI(VCC)< 10 V %/V 0.7 V 0.8 V CURRENT REGULATION, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS Current regulation threshold, VI(limit) VSENSE < VO(VSEL-LOW/HIGH) Delay time VSENSE pulsed above VVLOWV to IO = 10% of regulated value(1) Rise time IO increasing from 10% to 90% of regulated value. RSNS≥ 0.2 Ω, (1) MIN TYP MAX UNIT 0.095 0.1 0.105 V 0.1 1 ms 1 ms (1) Specified by design, not production tested. CURRENT SENSE RESISTOR, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS Externalcurrent sense resistor range (RSNS) 100 mA ≤ Ilim ≤ 1.2 A MIN TYP 0.083 MAX 1 UNIT Ω PRECHARGE CURRENT REGULATION, 0°C ≤ TJ ≤ 125°C PARAMETER Precharge current regulation TEST CONDITIONS VSENSE<VLOWV, 0.083 ≤ RSNS ≤ 1.0 Ω MIN TYP MAX 40 60 80 UNIT mA VCC UVLO COMPARATOR, 0°C ≤ TJ ≤ 125°C MIN TYP MAX UNIT Start threshold PARAMETER TEST CONDITIONS 4.35 4.43 4.50 V Stop threshold 4.25 4.33 4.40 V Hysteresis 50 mV APG/THERM COMPARATOR, 0°C ≤ TJ ≤ 125°C MIN TYP MAX UNIT Upper trip threshold PARAMETER TEST CONDITIONS 1.480 1.498 1.515 V Lower trip threshold 0.545 0.558 0.570 Input bias current 1 V µA LOWV COMPARATOR, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS MIN TYP MAX UNIT Start threshold 2.80 2.90 3.00 V Stop threshold 3.00 3.10 3.20 Hysteresis 100 V mV 3 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 ELECTRICAL CHARACTERISTICS CONTINUED over recommended operating junction temperature supply and input voltages, and VI (VCC) ≥ VI (IN) ( unless otherwise noted) HIGHV (RECHARGE) COMPARATOR, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS Start threshold MIN TYP MAX UNIT 3.80 3.90 4.00 V OVERV COMPARATOR, 0°C ≤ TJ ≤ 125°C MIN TYP MAX UNIT Start threshold PARAMETER TEST CONDITIONS 4.35 4.45 4.55 V Stop threshold 4.25 4.30 4.35 Hysteresis 50 V mV TAPERDET COMPARATOR, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS Trip threshold MIN TYP MAX 12 18.5 25 MIN TYP MAX UNIT mV EN LOGIC INPUT, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS High-level input voltage 2.25 V Low-level input voltage Input pulldown resistance UNIT 100 0.8 V 200 kΩ MAX UNIT VSEL LOGIC INPUT, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS High-level input voltage MIN TYP 2.25 V Low-level input voltage Input pulldown resistance 100 0.8 V 200 kΩ MAX UNIT TMR SEL INPUT 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS High-level input voltage MIN TYP 2.7 V Low-level input voltage VI(TMR SEL) ≤ 5V Input bias current 0.6 V 15 µA STAT1, STAT2 (bq24001, bq24003), 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS Output (low) saturation voltage MIN TYP IO = 10 mA IO = 4 mA Output (low) saturation voltage Output (high) saturation voltage Output (high) saturation voltage IO = –10 mA IO = –4 mA Output turn on/off time IO = ± 10 mA, C = 100 p(1) MAX UNIT 1.5 V 0.6 V VCC–1.5 VCC–0.5 V V 100 µs MAX UNIT (1) Assured by design, not production tested. POWER-ON RESET (POR), 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS MIN TYP POR delay See Note 1 1.2 3 ms POR falling-edge deglitch See Note 1 25 75 µs (1) Assured by design, not production tested. 4 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 ELECTRICAL CHARACTERISTICS CONTINUED over recommended operating junction temperature supply and input voltages, and VI (VCC) ≥ VI (IN) ( unless otherwise noted) APG/THERM DELAY, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS APG/THERM falling-edge deglitch MIN See Note 1 TYP 25 MAX 75 UNIT µs (1) Assured by design, not production tested. TIMERS, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS MIN TA = 25°C User selectable timer accuracy User-selectable TYP –15% UNIT 15% –20% Precharge and taper timer MAX 20% 22.5 minute THERMAL SHUTDOWN, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS MIN TYP MAX UNIT Thermal trip See Note 1 165 °C Thermal hysteresis See Note 1 10 °C (1) Assured by design, not production tested. CR PIN, 0°C ≤ TJ ≤ 125°C PARAMETER TEST CONDITIONS 0 < IO(CR) < 100 µA Output voltage MIN TYP MAX UNIT 2,816 2.85 2.88 V PIN ASSIGNMENTS bq24002, bq24003 PWP PACKAGE (TOP VIEW) bq24001 PWP PACKAGE (TOP VIEW) N/C IN IN VCC ISNS N/C APG/THERM EN VSEL GND/HEATSINK 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 N/C OUT OUT VSENSE AGND N/C STAT1 TMR SEL CR N/C N/C IN IN VCC ISNS N/C APG/THERM EN VSEL GND/HEATSINK 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 N/C OUT OUT VSENSE AGND STAT2 STAT1 TMR SEL CR N/C N/C – Do not connect 5 bq24001 bq24002 bq24003 www.ti.com 1 IN 2 IN 3 VCC bq24002, bq24003 RGW PACKAGE (TOP VIEW) 4 ISNS 5 APG/THERM 1 IN 2 IN 3 VCC bq24001 RGW PACKAGE (TOP VIEW) 4 ISNS 5 APG/THERM SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 EN 6 20 N/C EN 6 20 N/C VSEL 7 19 N/C VSEL 7 19 N/C GND 8 18 N/C GND 8 18 N/C TMR SEL 11 TMR SEL 11 VSENSE 15 16 OUT AGND 14 N/C 10 STAT2 13 16 OUT STAT1 12 N/C 10 VSENSE 15 17 OUT AGND 14 CR 9 N/C 13 17 OUT STAT1 12 CR 9 N/C – Do Not Connect Terminal Functions TERMINAL NAME I/O DESCRIPTION NO. NO. 16 14 APG/THERM 7 5 I Adapter power good input/thermistor sense input CR 12 9 I Internal regulator bypass capacitor EN 8 6 I Charge-enableinput. Active-high enable input with internal pull down. Low-current stand-by mode active when EN is low. GND/HEATSINK 10 8 IN 2, 3 1, 2 I Input voltage. This input provides the charging voltage for the battery. I Current sense input AGND ISNS 5 4 N/C 1, 6, 11, 15, 20 10, 13, 18–20 OUT Ground pin; connect close to the negative battery terminal. Ground pin; connect to PowerPAD heat-sink layout pattern. No connect. These pins must be left floating. Pin 15 is N/C on bq24001PWP only. Pin 13 is N/C on bq24001RGW only. 18, 19 16, 17 O Charge current output STAT1 14 12 O Status display output 1 STAT2 15 13 O Status display output 2 (for bq24002 and bq24003 only) TMR SEL 13 11 I Charge timer selection input VCC 4 3 I Supply voltage VSEL 9 7 I 4.1 V or 4.2 V charge regulation selection input VSENSE 17 15 I Battery voltage sense input 6 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 FUNCTIONAL BLOCK DIAGRAM OUT IN + VSENSE TaperDet – VCC – + – Vilim + 0.2*Vilim ISNS Vref AGND + Precharge – GND/ HEATSINK LowV OverV ChipEN – R8 Vuvlo LowV + + Vref – Power On Delay APG/ THERM – VSEL R9 HighV Bias and Ref Generator + EN H: Vreg = 4.2 V/Cell L: Vreg = 4.1 V/Cell + Vuvlo ChargeOK UVS Vref CLRFLT – + PWRDWN – Thermal Shutdown UVS VCC TaperDet STAT1 PWRDWN PWRDWN OSC Charge Control, Charge Timer and Display Logic TMR SEL VCC STAT2 REG ChargeOK CR Two Open Drain Outputs for bq24002 7 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 TYPICAL CHARACTERISTICS OUTPUT VOLTAGE vs OUTPUT CURRENT OUTPUT VOLTAGE vs JUNCTION TEMPERATURE 4.24 4.24 VIN = 5 V VIN = 5 V TA = 25°C 4.22 4.22 VSEL = VCC VSEL = VCC 4.20 VO – Output Voltage – V VO – Output Voltage – V 4.20 4.18 4.16 4.14 4.12 VSEL = VSS 4.18 4.16 4.14 4.12 VSEL = VSS 4.10 4.10 4.08 4.08 4.06 –50 4.06 0 200 400 600 800 1000 1200 0 Figure 1 150 CURRENT SENSE VOLTAGE vs INPUT VOLTAGE 4.24 103 IO = 100 mA TA = 25°C IO = 100 mA TA = 25°C VSEL = VCC 102 Current Sense Voltage – mV 4.20 VO – Output Voltage – V 100 Figure 2 OUTPUT VOLTAGE vs INPUT VOLTAGE 4.22 50 TJ – Junction Temperature – °C IO – Output Current – mA 4.18 4.16 4.14 4.12 VSEL = VSS 4.10 101 100 99 98 4.08 4.06 97 5 6 7 8 VI – Input Voltage – V Figure 3 8 9 10 5 6 7 8 VI – Input Voltage – V Figure 4 9 10 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 TYPICAL CHARACTERISTICS CURRENT SENSE VOLTAGE vs JUNCTION TEMPERATURE QUIESCENT CURRENT vs INPUT VOLTAGE 103 0.5 IO = 100 mA TA = 25°C TA = 25°C 0.4 Quiescent Current – mA Current Sense Voltage – mV 102 VCC = 10 V 101 100 VCC = 5 V 99 0.3 0.2 0.1 98 –50 0.0 0 50 100 150 5 6 TJ – Junction Temperature – °C 8 9 10 VI – Input Voltage – V Figure 5 Figure 6 QUIESCENT CURRENT (POWER DOWN) vs INPUT VOLTAGE DROPOUT VOLTAGE vs INPUT VOLTAGE 600 30 TA = 25°C TA = 25°C 500 Dropout Voltage – mV 25 Quiescent Current – nA 7 20 15 10 400 1200 mA 300 800 mA 200 400 mA 100 5 100 mA 0 5 6 7 8 VI – Input Voltage – V Figure 7 9 10 0 4.5 5.5 6.5 7.5 8.5 9.5 VI – Input Voltage – V Figure 8 9 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 TYPICAL CHARACTERISTICS DROPOUT VOLTAGE vs OUTPUT CURRENT DROPOUT VOLTAGE vs JUNCTION TEMPERATURE 600 800 IO = 1.2 A TA = 25°C 700 Dropout Voltage – mV Dropout Voltage – mV 500 400 VCC = 5 V 300 200 VCC = 10 V 100 600 VIN = 5 V 500 400 VIN = 10 V 300 200 0 0 200 400 600 800 1000 100 –50 1200 0 50 100 150 TJ – Junction Temperature – °C IO – Output Current – mA Figure 9 Figure 10 REVERSE CURRENT vs JUNCTION TEMPERATURE REVERSE CURRENT LEAKAGE vs VOLTAGE ON OUT PIN 6 4.0 VOUT = 4.3 V TA = 25°C 3.5 IR – Reverse Current Leakage – µA IR – Reverse Current – µA 5 4 3 2 1 3.0 2.5 2.0 1.5 1.0 0.5 0 –50 0.0 0 50 100 TJ – Junction Temperature – °C Figure 11 10 150 5 6 7 8 VO – Voltage on Out Pin – V Figure 12 9 10 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 APPLICATION INFORMATION U1 VCC 1 R1 0.1 Ω 2 DC+ C1 10 µF + VCC 3 4 DC– 5 6 C2 0.1 µF 7 8 9 10 N/C IN N/C OUT IN OUT VCC ISNS VSENSE AGND N/C STAT2 APG/THM STAT1 EN TMR SEL VSEL GND CR N/C 20 19 PACK+ 18 + 17 – 16 PACK– 15 C4 1 µF 14 13 TEMP 12 11 VCC C3 0.22 µF Battery Pack R4 500 Ω bq24002PWP D1 R5 500 Ω R2 18.7 kΩ D2 R3 95.3 kΩ Figure 13. Li-Ion/Li-Pol Charger 11 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 APPLICATION INFORMATION FUNCTIONAL DESCRIPTION The bq2400x supports a precision current- and voltage-regulated Li-Ion charging system suitable for cells with either coke or graphite anodes. See Figure 14 for a typical charge profile and Figure 15 for an operational flowchart. Preconditioning Phase Current Regulation Phase Voltage Regulation and Charge TerminationPhase Regulation Voltage (VOUT) Regulation Current (Ilim) Charge Voltage Minimum Charge Voltage (LowV) Preconditioning Current (IPRECHG) Charge Current Taper Detect 22.5 Minutes 22.5 Minutes Charge Timer (3, 4.5 or 6 Hours) Figure 14. Typical Charge Profile 12 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 POR Yes VI(VSENSE) < V(LOWV)? Regulate I (PRECHG) Reset and Start 22.5 min Timer Indicate Pre– Charge No Reset All Timers, Start Charge Timer (TMR SEL input ) Yes VI(VSENSE) > V(OVERV)? No Regulate Current or Voltage Indicate Charge No VI(VSENSE) < V(LOWV)? Yes VI(VSENSE) > V(OVERV)? Yes 22.5min Timer Expired? No No Yes Yes Charge timer Expired? No Fault Condition Yes Indicate Fault VI(VSENSE) < V(LOWV)? No Taper Detected? Start 22.5 minute Timer Yes POR? or APG/THERM toggle? or EN toggle? No Indicate DONE Yes No 22.5min Timer 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 13 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 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 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. 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 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 bq24002PWP RT1 RT2 Figure 16. Temperature Sensing Circuit 14 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 U1 VCC 1 2 DC+ Vcc 3 4 Temp Fault 5 VTP1 6 R1 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 EN TMR SEL VSEL CR GND N/C 20 19 18 17 16 15 14 13 12 11 GND bq24002PWP 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 VAPG 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 RSNS 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 bq24002PWP Figure 19. Current Sensing Circuit 15 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 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 + Vilim I REG where IREG is the desired charging current. The output stage is totem pole for the bq24001 and bq24003 and open-drain for the bq24002. The following tables summarize the operation of the three options: Table 1. bq24001 (Single LED) CHARGE STATE STAT1 Precharge ON (LOW) Fast charge ON (LOW) Voltage Monitoring and Regulation FAULT 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. Done (>90%) OFF (HIGH) Sleep-mode OFF (HIGH) APG/Therm invalid OFF (HIGH) Thermal shutdown OFF (HIGH) Battery absent OFF (HIGH) VSEL State (see Note) CHARGE REGULATION VOLTAGE Low 4.1 V High NOTE: VSEL should not be left floating. 4.2 V Flashing (1 Hz, 50% duty cycle) Table 2. bq24002 (2 Individual LEDs) CHARGE STATE Precharge Fast charge Charge Termination STAT1 (RED) STAT2 (GREEN) ON (LOW) OFF ON (LOW) OFF Flashing (1 Hz, 50% duty cycle) OFF Done (>90%) The bq2400x continues with the charge cycle until termination by one of the two possible termination conditions: FAULT OFF ON (LOW) Sleep-mode OFF OFF 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. APG/Therm invalid OFF OFF Thermal shutdown OFF OFF OFF(1) Battery absent OFF (1) If thermistor is used, then the Green LED is off. Table 3. bq24003 (Single Bicolor LED) CHARGE STATE LED1 (RED) LED2 (GREEN) APPARENT COLOR RED TMRSEL STATE Floating(1) CHARGE TIME Precharge ON (LOW) OFF (HIGH) 3 hours Fast charge ON (LOW) OFF (HIGH) RED Low 6 hours FAULT ON (LOW) ON (LOW) YELLOW 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) 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. (1) If thermistor is used, then the Green LED is off. Charge Status Display Thermal Shutdown The three available options allow the user to configure the charge status display for single LED (bq24001), two individual LEDs (bq24002) or a bicolor LED (bq24003). 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. 16 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 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 10kΩ 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). 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. 17 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 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, fine-pitch, surface-mount package can be reliably achieved. 18 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. bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 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 6 7 8 Copper Heat-Sink Area – cm2 Figure 21 19 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 THERMAL INFORMATION 3.5 3.5 TA = 25°C TA = 55°C 300 ft/min 3 PD – Power Dissipation Limit – W PD – Power Dissipation Limit – W 3 150 ft/min 2.5 2 Natural Convection 1.5 1 0.5 0 300 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) (b) 3.5 TA = 105°C PD – Power Dissipation Limit – W 3 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 20 8 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 MECHANICAL DATA PWP (R-PDSO-G**) PowerPAD PLASTIC SMALL-OUTLINE 20 PINS SHOWN 0,30 0,19 0,65 20 0,10 M 11 Thermal Pad (See Note D) 4,50 4,30 0,15 NOM 6,60 6,20 Gage Plane 1 10 0,25 A 0°–ā8° 0,75 0,50 Seating Plane 0,15 0,05 1,20 MAX PINS ** 0,10 14 16 20 24 28 A MAX 5,10 5,10 6,60 7,90 9,80 A MIN 4,90 4,90 6,40 7,70 9,60 DIM 4073225/F 10/98 NOTES:A. B. C. D. All linear dimensions are in millimeters. This drawing is subject to change without notice. Body dimensions do not include mold flash or protrusions. The package thermal performance may be enhanced by bonding the thermal pad to an external thermal plane. This pad is electrically and thermally connected to the backside of the die and possibly selected leads. E. Falls within JEDEC MO-153. PowerPAD is a trademark of Texas Instruments. 21 bq24001 bq24002 bq24003 www.ti.com SLUS462D – SEPTEMBER 2000 – REVISED MAY 2002 MECHANICAL DATA RGW (S-PQFP-N20) PLASTIC QUAD FLATPACK 5,15 4,85 5,15 4,85 Pin 1 Index Area Top and Bottom 1,00 0,80 0,20 REF. Seating Plane 0,05 0,00 0,08 3,25 SQ MAX 20X 0,75 0,35 0,65 1 5 20 6 16 10 15 11 20X 2,60 Exposed Thermal Die Pad (See Note D) 0,38 0,23 0,10 NOTES:A. B. C. D. E. 22 4204100/A 01/02 All linear dimensions are in millimeters. This drawing is subject to change without notice. Quad Flatpack, No-leads, (QFN) package configuration. The package thermal performance may be enhanced by bonding the thermal die pad to an external thermal plane. Falls within JEDEC M0-220. 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. 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