BQ2054PNG4

bq2054 Lithium Ion Fast-Charge IC Features General Description ➤ Safe charge of Lithium Ion battery packs The bq2054 Lithium Ion FastCharge IC is designed to optimize charging of lithium ion (Li-Ion) chemistry batteries. A flexible pulse-width modulation regulator allows the bq2054 to control voltage and current during charging. The regulator frequency is set by an external capacitor for design flexibility. The switch-mode design keeps power dissipation to a minimum. ➤ Voltage-regulated currentlimited charging ➤ Fast charge terminated by selectable minimum current; safety backup termination on maximum time ➤ Charging continuously qualified by temperature and voltage limits ➤ Pulse-width modulation control ideal for high-efficiency switchmode power conversion The bq2054 measures battery temperature using an external thermistor for charge qualification. Charging begins when power is applied or on battery insertion. ➤ Direct LED control outputs display charge status and fault conditions For safety, the bq2054 inhibits charging until the battery voltage and temperature are within con- Pin Connections Pin Names TM 1 16 LED2/DSEL ICTL 2 15 LED1 BAT 3 14 MOD VCOMP 4 13 VCC ICOMP 5 12 VSS ITERM 6 11 LCOM SNS 7 10 LED3 TS 8 9 TPWM 16-Pin Narrow DIP or SOIC figured limits. If the battery voltage is less than the low-voltage threshold, the bq2054 provides low-current conditioning of the battery. A constant current-charging phase replenishes up to 70% of the charge capacity, and a voltage-regulated phase returns the battery to full. The charge cycle terminates when the charging current falls below a user-selectable current limit. For safety, charging terminates after maximum time and is suspended if the temperature is outside the preconfigured limits. The bq2054 provides status indications of all charger states and faults for accurate determination of the battery and charge system conditions. TPWM Regulator timebase input LED3 Charge status output 3 LCOM Common LED output Battery voltage input VSS System ground VCOMP Voltage loop comp input VCC 5.0V± 10% power ICOMP Current loop comp input MOD Modulation control output ITERM Minimum current termination select input LED1 Charge status output 1 SNS Sense resistor input LED2/ DSEL Charge status output 2/ Display select input TS Temperature sense input TM Time-out programming input ICTL Inrush current control output BAT PN205401.eps 6/99 H 1 bq2054 TS Pin Descriptions TM This input is used to monitor battery temperature. An external resistor divider network sets the lower and upper temperature thresholds. See Figure 6 and Equations 3 and 4. Time-out programming input This input sets the maximum charge time. The resistor and capacitor values are determined using Equation 5. Figure 7 shows the resistor/capacitor connection. ICTL TPWM LCOM Battery voltage input MOD LED1– LED3 Voltage loop compensation input Minimum current termination select DSEL Display select input This three-level input controls the LED1–3 charge display modes. See Table 1. Current loop compensation input This input uses an external R-C network for current loop stability. SNS Charger display status 1–3 outputs These charger status output drivers are for the direct drive of the LED display. Display modes are shown in Table 1. These outputs are tri-stated during initialization so that DSEL can be read. This three-state input is used to set IMIN for fast charge termination. See Table 2. ICOMP Current-switching control output MOD is a pulse-width modulated push/pull output that is used to control the charging current to the battery. MOD switches high to enable current flow and low to inhibit current flow. This input uses an external R-C network for voltage loop stability. ITERM Common LED output Common output for LED1–3. This output is in a high-impedance state during initializ a t i o n t o r e a d programming input on DSEL. BAT is the battery voltage sense input. This potential is generally developed using a high-impedance resistor divider network connected between the positive and the negative terminals of the battery. See Figure 4 and Equation 1. VCOMP Regulation timebase input This input uses an external timing capacitor to ground to set the pulse-width modulation (PWM) frequency. See Equation 7. Inrush current control output ICTL is driven low during the fault or charge-complete states of the chip. It is used to disconnect the capacitor across the battery pack terminals, preventing inrush currents from tripping overcurrent protection features in the pack when a new battery is inserted. BAT Temperature sense input VCC VCC supply 5.0V, ± 10% power Charging current sense input VSS Battery current is sensed via the voltage developed on this pin by an external sense resistor, RSNS, connected in series with the negative terminal of the battery pack. See Equation 6. 2 Ground bq2054 Thermal monitoring continues throughout the charge cycle, and the bq2054 enters the Charge Pending state when the temperature out of range. (There is one exception; if the bq2054 is in the Fault state—see below—the out-of-range temperature is not recognized until the bq2054 leaves the Fault state.) All timers are suspended (but not reset) while the bq2054 is in Charge Pending. When the temperature comes back into range, the bq2054 returns to the point in the charge cycle where the out-of-range temperature was detected. Charge Algorithm The bq2054 uses a two-phase fast charge algorithm. In phase 1, the bq2054 regulates constant current (ISNS = IMAX) until VCELL (= VBAT - VSNS) rises to VREG. The bq2054 then transitions to phase 2 and regulates constant voltage (VCELL = VREG) until the charging current falls below the programmed IMIN threshold. The charging current must remain below IMIN for 120 ± 40ms before a valid fast charge termination is detected. Fast charge then terminates, and the bq2054 enters the Charge Complete state. See Figures 1 and 2. When the temperature is valid, the bq2054 then regulates current to ICOND (=IMAX/5). After an initial holdoff period tHO (which prevents the chip from reacting to transient voltage spikes that may occur when charge current is first applied), the chip begins monitoring VCELL. If VCELL does not rise to at least VMIN before the expiration of time-out limit tMTO (e.g. the cell has failed short), the bq2054 enters the Fault state. If VMIN is achieved before expiration of the time limit, the chip begins fast charging. Charge Qualification The bq2054 starts a charge cycle when power is applied while a battery is present or when a battery is inserted. Figure 2 shows the state diagram for pre-charge qualification and temperature monitoring. The bq2054 first checks that the battery temperature is within the allowed, user-configurable range. If the temperature is out of range, the bq2054 enters the Charge Pending state and waits until the battery temperature is within the allowed range. Charge Pending is enunciated by LED3 flashing. Once in the Fault state, the bq2054 waits until VCC is cycled or a new battery insertion is detected. It then starts a new charge cycle and begins the qualification process again. Current IMAX Qualification VREG Voltage Fast Charge Phase 1 VMIN Phase 2 Voltage ICOND Current IMIN Time GR205401.eps Figure 1. bq2054 Charge Algorithm 3 bq2054 Chip On VCC 4.5V Temperature Out of Range or Thermistor Absent Temperature Checks On Present VLCO < VBAT < VHCO Temperature in Range Qualification Test Battery Status? Absent VBAT < VLCO or VBAT > VHCO VBAT < VMIN Current Regulation @ ICOND Fail: t = tQT or VBAT < VLCO VBAT > VHCO Fault LED3 =1 MOD = 0 PASS: VBAT > VMIN VBAT VBAT Phase 1 I = IMAX VBAT < VREG Fast Charge VBAT > VREG Phase 2 V = VREG ISNS > IMIN ISNS < IMIN or t > tMTO VBAT VLCO VLCO or t > t > tMTO or VBAT < VLCO or VBAT > VHCO VBAT < VLCO or VBAT > VHCO VHCO Charge Pending LED3 flash MOD = 0 Temperature Out of Range or Thermistor Absent Temperature In Range, Return to Original State Charge Complete or VBAT VHCO FG205401.eps Figure 2. bq2054 State Diagram 4 bq2054 Charge Status Display Configuring the Display Mode and IMIN Charge status is enunciated by the LED driver outputs LED1–LED3. Three display modes are available in the bq2054; the user selects a display mode by configuring pin DSEL. Table 1 shows the three display modes. DSEL/LED2 is a bi-directional pin with two functions; it is an LED driver pin as an output and a programming pin as an input. The selection of pull-up, pull-down, or no pull resistor programs the display mode on DSEL per Table 1. The bq2054 latches the programming data sensed on the DSEL input when any one of the following three events occurs: The bq2054 does not distinguish between an overvoltage fault and a “battery absent” condition. The bq2054 enters the Fault state, enunciated by turning on LED3, whenever the battery is absent. The bq2054, therefore, gives an indication that the charger is on even when no battery is in place to be charged. 1. VCC rises to a valid level. 2. The bq2054 leaves the Fault state. 3. The bq2054 detects battery insertion. The LEDs go blank for approximately 750ms (typical) while new programming data is latched. Table 1. bq2054 Display Output Summary Mode DSEL = 0 (Mode 1) DSEL = 1 (Mode 2) DSEL = Float (Mode 3) Note: Charge Action State LED1 LED2 LED3 Battery absent or over-voltage fault Low Low High Pre-charge qualification Flash Low Low Fast charging High Low Low Charge complete Low High Low Charge pending (temperature out of range) X X Flash Charging fault X X High Battery absent or over-voltage fault Low Low High Pre-charge qualification High High Low Fast charge Low High Low Charge complete High Low Low Charge pending (temperature out of range) X X Flash Charging fault X X High Battery absent or over-voltage fault Low Low High Pre-charge qualification Flash Flash Low Fast charge: current regulation Low High Low Fast charge: voltage regulation High High Low Charge complete High Low Low Charge pending (temperature out of range) X X Flash Charging fault X X High 1 = VCC; 0 = VSS; X = LED state when fault occurred; Flash = 1 6 sec. low, 1 6 sec high. 5 bq2054 Fast charge terminates when the charging current drops below a minimum current threshold programmed by the value of ITERM (see Table 2) and remains below that level for 120 ± 40ms. These parameters are typically specified by the battery manufacturer. The total resistance presented across the battery pack by RB1 + RB2 should be between 150kΩ and 1MΩ. The minimum value ensures that the divider network does not drain the battery excessively when the power source is disconnected. Exceeding the maximum value increases the noise susceptibility of the BAT pin. Table 2. IMIN Termination Thresholds ITERM IMIN 0 IMAX/10 The current sense resistor, RSNS (see Figure 5), determines the fast charge current. The value of RSNS is given by the following: 1 IMAX/20 Equation 2 Float IMAX/30 I MAX = Figure 3 shows the bq2054 configured for display mode 2 and IMIN = IMAX/10. where: n Voltage and Current Monitoring Both VHCO and IMIN terminations are ignored during the first 1.33 ± 0.19 seconds of both the Charge Qualification and Fast Charge phases. This condition prevents premature termination due to voltage spikes that may occur when charge is first applied. The resistor values are calculated from the following: Equation 1 RB1 N * VREG = −1 RB2 205 . V where: N = Number of cells in series n VREG = Desired fast-charging voltage per cell IMAX = Desired maximum charge current Hold-Off Period The bq2054 monitors battery pack voltage at the BAT pin. The user must implement a voltage divider between the positive and negative terminals of the battery pack to present a scaled battery pack voltage to the BAT pin. The bq2054 also uses the voltage across a sense resistor (RSNS) between the negative terminal of the battery pack and ground to monitor the current into the pack. See Figure 4 for the configuration of this network. n 0.250 V R SNS 6 bq2054 VCC LED2/DSEL LED1 10K 1K 16 15 1K VCC VSS 6 LCOM LED3 13 12 11 1K 10 bq2054 VSS FG205402.eps Figure 3. Configured Display Mode/IMIN Threshold VCC BAT + RB1 BAT 13 12 3 VCC RB2 VSS SNS bq2054 7 BAT RSNS VSS FG205403.eps Figure 4. Configuring the Battery Divider 7 bq2054 Battery Insertion and Removal Temperature Monitoring VCELL is interpreted by the bq2054 to detect the presence or absence of a battery. The bq2054 determines that a battery is present when V CELL is between the High-Voltage Cutoff (V HCO = V REG + 0.25V) and the Low-Voltage Cutoff (VLCO = 0.8V). When VCELL is outside this range, the bq2054 determines that no battery is present and transitions to the Fault state. Transitions into and out of the range between VLCO and VHCO are treated as battery insertions and removals, respectively. The VHCO limit also implicitly serves as an overvoltage charge termination. The bq2054 monitors temperature by examining the voltage presented between the TS and SNS pins by a resistor network that includes a Negative Temperature Coefficient (NTC) thermistor. Resistance variations around that value are interpreted as being proportional to the battery temperature (see Figure 6). The temperature thresholds used by the bq2054 and their corresponding TS pin voltage are: n Inrush Current Control n Whenever the bq2054 is in the fault or charge-complete state, the ICTL output is driven low. This output can be used to disconnect the capacitor usually present in the charger across the positive and negative battery terminals, preventing the cap from supplying large inrush currents to a newly inserted battery. Such inrush currents may trip the overcurrent protection circuitry usually present in Li-Ion battery packs. n TCO (Temperature Cutoff): Higher limit of the temperature range in which charging is allowed. VTCO = 0.4 * VCC HTF (High-Temperature Fault): Threshold to which temperature must drop after temperature cutoff is exceeded before charging can begin again. VHTF = 0.44 * VCC LTF (Low-Temperature Fault): Lower limit of the temperature range in which charging is allowed. VLTF = 0.6 * VCC VCC VCC RT1 VCC RT2 VSS SNS TS 7 NTC Thermistor RT ˚t VLTF = 0.6VCC VHTF = 0.44VCC VTCO = 0.4VCC LTF HTF TCO BAT - 8 RSNS VSS Hotter VSS Figure 5. Configuring Temperature Sensing Figure 6. Voltage Equivalent of Temperature 8 Temperature 12 Voltage bq2054 13 Colder bq2054 A resistor-divider network can be implemented that presents the defined voltage levels to the TS pin at the desired temperatures (see Figure 6). VCC R The equations for determining RT1 and RT2 are: 1 Equation 3 0.6 * VCC (VCC − 0.250 ) = RT1 * (RT2 + R LTF ) 1+ (RT2 * R LTF ) TM C VCC VSS Equation 4 0.44 = 1+ 1 RT1 * (RT2 + R HTF ) (RT2 * R HTF ) 13 12 bq2054 where: VSS n RLTF = thermistor resistance at LTF n RHTF = thermistor resistance at HTF FG205406.eps Figure 7. R-C Network for Setting MTO TCO is determined by the values of RT1 and RT2. 1% resistors are recommended. Disabling Temperature Sensing Charge Regulation Temperature sensing can be disabled by placing 10kΩ resistors between TS and SNS and between SNS and VCC. The bq2054 controls charging through pulse-width modulation of the MOD output pin, supporting both constant-current and constant-voltage regulation. Charge current is monitored at the SNS pin, and charge voltage is monitored at the BAT pin. These voltages are compared to an internal reference, and the MOD output modulated to maintain the desired value. Maximum Time-Out MTO is programmed from 1 to 24 hours by an R-C network on the TM pin (see Figure 7) per the equation: Voltage at the SNS pin is determined by the value of resistor RSNS, so nominal regulated current is set by: Equation 5 Equation 6 tMTO = 0.5 * R * C IMAX = 0.250V/RSNS Where R is in kΩ and C is in µF, tMTO is in hours. The maximum value for C (0.1µF) is typically used. The switching frequency of the MOD output is determined by an external capacitor (CPWM) between the pin TPWM and ground, per the following: The MTO timer is reset at the beginning of fast charge and when fast charge transitions from the current regulated to the voltage regulated mode. If MTO expires during the current regulated phase, the bq2054 enters the Fault state and terminates charge. If the MTO timer expires during the voltage regulated phase, fast charging terminates and the bq2054 enters the Charge Complete state. Equation 7 FPWM = 0.1/CPWM Where C is in µF and F is in kHz. A typical switching rate is 100kHz, implying CPWM = 0.001µF. MOD pulse width is modulated between 0 and 90% of the switching period. The MTO timer is suspended (but not reset) during the out-of-range temperature (Charge Pending) state. To prevent oscillation in the voltage and current control loops, frequency compensation networks (C or R-C) are typically required on the VCOMP and ICOMP pins (respectively). 9 bq2054 Absolute Maximum Ratings Symbol Parameter Minimum Maximum Unit VCC VCC relative to VSS -0.3 +7.0 V VT DC voltage applied on any pin excluding VCC relative to VSS -0.3 +7.0 V TOPR Operating ambient temperature -20 +70 °C TSTG Storage temperature -55 +125 °C TSOLDER Soldering temperature - +260 °C Note: Notes Commercial 10 sec. max. Permanent device damage may occur if Absolute Maximum Ratings are exceeded. Functional operation should be limited to the Recommended DC Operating Conditions detailed in this data sheet. Exposure to conditions beyond the operational limits for extended periods of time may affect device reliability. 10 bq2054 DC Thresholds Symbol (TA = TOPR; VCC = 5V ± 10%) Parameter Rating Unit Tolerance Notes Internal reference voltage 2.05 V 1% Temperature coefficient -0.5 mV/°C 10% VLTF TS maximum threshold 0.6 * VCC V ± 0.03V Low-temperature fault VHTF TS hysteresis threshold 0.44 * VCC V ± 0.03V High-temperature fault VTCO TS minimum threshold 0.4 * VCC V ± 0.03V Temperature cutoff VHCO High cutoff voltage 2.3V V 1% VMIN Under-voltage threshold at BAT 0.2 * VCC V ± 0.03V VLCO Low cutoff voltage 0.8 V ± 0.03V 0.250 V 10% IMAX VSNS Current sense at SNS 0.050 V 10% ICOND TA = 25°C VREF 11 bq2054 Recommended DC Operating Conditions (TA = TOPR) Symbol Parameter VCC Supply voltage VTEMP Minimum Typical Maximum Unit Notes 4.5 5.0 5.5 V Temperature sense voltage 0 - VCC V VTS - VSNS VCELL Per cell battery voltage input 0 - VCC V VBAT - VSNS ICC Supply current - 2 4 mA Outputs unloaded DSEL tri-state open detection -2 - 2 µA Note 2 ITERM tri-state open detection -2 2 µA IIZ VIH Logic input high VCC-0.3 - - V DSEL, ITERM VIL Logic input low - - VSS+0.3 V DSEL, ITERM LED1-3, ICTL, output high VCC-0.8 - - V IOH ≤ 10mA MOD output high VCC-0.8 - - V IOH ≤ 10mA LED1-3, ICTL, output low - - VSS+0.8V V IOL ≤ 10mA MOD output low - - VSS+0.8V V IOL ≤ 10mA LCOM output low - - VSS+0.5 V IOL ≤ 30mA LED1-3, ICTL, source -10 - - mA VOH =VCC-0.5V MOD source -5.0 - - mA VOH =VCC-0.5V LED1-3, ICTL, sink 10 - - mA VOL = VSS+0.5V MOD sink 5 - - mA VOL = VSS+0.8V LCOM sink 30 - - mA VOL = VSS+0.5V DSEL logic input low source - - +30 µA V = VSS to VSS+ 0.3V, Note 2 ITERM logic input low source - - +70 µA V = VSS to VSS+ 0.3V DSEL logic input high source -30 - - µA V = VCC - 0.3V to VCC ITERM logic input high source -70 - - µA V = VCC - 0.3V to VCC VOH VOL IOH IOL IIL IIH Notes: 1. All voltages relative to VSS except where noted. 2. Conditions during initialization after VCC applied. 12 bq2054 Impedance Symbol Parameter Minimum Typical Maximum Unit Notes RBATZ BAT pin input impedance 50 - - MΩ RSNSZ SNS pin input impedance 50 - - MΩ RTSZ TS pin input impedance 50 - - MΩ RPROG1 Soft-programmed pull-up or pull-down resistor value (for programming) - - 10 kΩ DSEL RPROG2 Pull-up or pull-down resistor value - - 3 kΩ ITERM RMTO Charge timer resistor 20 - 480 kΩ Timing (TA = TOPR; VCC = 5V ± 10%) Symbol Parameter Minimum Typical Maximum Unit Notes See Figure 7 tMTO Charge time-out range 1 - 24 hours tQT Pre-charge qual test time-out period - tMTO - - tHO Termination hold-off period 1.14 - 1.52 sec. tIMIN Min. current detect filter period 80 160 msec. FPWM PWM regulator frequency range - 100 kHz CPWM = 0.001µF (equation 7) Capacitance Symbol Parameter Minimum Typical Maximum Unit CMTO Charge timer capacitor - - 0.1 µF CPWM PWM R-C capacitance - 0.001 - µF 13 bq2054 16-Pin DIP Narrow (PN) 16-Pin PN (0.300" DIP) Inches Millimeters Dimension Min. Max. Min. Max. A 0.160 0.180 4.06 4.57 A1 0.015 0.040 0.38 1.02 B 0.015 0.022 0.38 0.56 B1 0.055 0.065 1.40 1.65 C 0.008 0.013 0.20 0.33 D 0.740 0.770 18.80 19.56 E 0.300 0.325 7.62 8.26 E1 0.230 0.280 5.84 7.11 e 0.300 0.370 7.62 9.40 G 0.090 0.110 2.29 2.79 L 0.115 0.150 2.92 3.81 S 0.020 0.040 0.51 1.02 16-Pin SOIC Narrow (SN) 16-Pin SN (0.150" SOIC) Inches D e B E H A C A1 .004 L 14 Millimeters Dimension Min. Max. Min. Max. A 0.060 0.070 1.52 1.78 A1 0.004 0.010 0.10 0.25 B 0.013 0.020 0.33 0.51 C 0.007 0.010 0.18 0.25 D 0.385 0.400 9.78 10.16 E 0.150 0.160 3.81 4.06 e 0.045 0.055 1.14 1.40 H 0.225 0.245 5.72 6.22 L 0.015 0.035 0.38 0.89 bq2054 Data Sheet Revision History Change No. Page No. 1 Description Nature of Change 5, 7, 8, 10 Value Change 2 5, 10 3 Changed VSNS and IMAX Value Change Changed VREF 10 Coefficient Addition Temperature coefficient added 4 5 New state diagram Diagram inserted 4 1, 2, 8, 12 4 3, 5, 13 5 11 VHCO Rating changed to 2.3V VHCO Tolerance changed to 1% Changed values for VHCO 6 13 tQT in Timing Specifications tQT changed from (0.16 ∗ tMTO) to tMTO 7 5 ITERM in Table 2 Z changes to Float 7 8 Figure 6 RB1 and RB2 changed to RT1 and RT2 8 10 TOPR Deleted industrial temperature range. Notes: NC pin replaced with ICTL Termination hold-off period added IMIN detect filtering added Change 3 = April 1996 C changes from Dec. 1995 B. Change 4 = Sept. 1996 D changes from April 1996 C. Change 5 = Nov. 1996 E changes from Sept. 1996 D. Change 6 = Oct. 1997 F changes from Nov. 1996 E. Change 7 = Oct. 1997 G changes from Oct. 1997 F. Change 8 = June 1999 H changes from Oct. 1997 G. Ordering Information bq2054 Package Option: PN = 16-pin plastic DIP SN = 16-pin narrow SOIC Device: bq2054 Li-Ion Fast-Charge IC 15 PACKAGE OPTION ADDENDUM www.ti.com 14-Oct-2022 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) Device Marking (3) Samples (4/5) (6) BQ2054PN ACTIVE PDIP N 16 25 RoHS & Green NIPDAU N / A for Pkg Type -20 to 70 2054PN-G Samples BQ2054SN ACTIVE SOIC D 16 40 RoHS & Green NIPDAU Level-1-260C-UNLIM -20 to 70 2054 (-G, G) Samples BQ2054SNTR ACTIVE SOIC D 16 2500 RoHS & Green NIPDAU Level-1-260C-UNLIM -20 to 70 2054 (-G, G) Samples (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of