Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsPMICsPMIC - battery management Charge management Li-Ion SOIC 16 N Surface-mount

Features

➤

Safe charge of Li-Ion battery

packs

➤

Pulse-width modulation control

for current and voltage reg-

ulation

➤

Programmable high-side/low-side

current-sense

➤

Fast charge terminated by se

lectable minimum current; safety

backup termination at maximum

time

➤

Pre-charge qualification detects

shorted or damaged cells and

conditions battery

➤ Charging continuously qualified

by temperature and voltage limits

➤ Direct LED control outputs to

display charge status and fault

conditions

General Description

The bq2954 Li-Ion Charge-Manage

ment IC uses a flexible pulse-width

modulation regulator to control volt

age and current during charging.

The regulator frequency is set by an

external capacitor for design flexi

bility. The switch-mode design mini

mizes power dissipation.

For safety, the bq2954 inhibits fast

charging until the battery voltage

and temperature are within config

ured limits. If the battery voltage is

less than the low-voltage threshold,

the bq2954 provides low-current

conditioning of the battery.

For charge qualifiction, the bq2954

uses an external thermistor to mea-

sure battery temperature. Charging

begins when power is applied or the

battery is inserted

The bq2954 charges a battery in two

phases. First a constant-current

phase replenishes approximately

70% of battery capacity. Then a volt

age-regulation phase completes the

battery charge.

The bq2954 provides status indica

tions of all charger states and faults

for accurate determination of the

battery and charge-system condi

tions.

TM Time-out programming

input

CHG Charge active output

BAT Battery voltage input

VCOMP Voltage loop comp input

ICOMP Current loop comp input

TERM

Minimum current

termination select input

SNS Sense resistor input

TS Temperature sense input

PN295401.eps

16-Pin Narrow

DIP or SOIC

LED

/DSEL

LED

/CSEL

MOD

LCOM

BTST

TPWM

CHG

BAT

VCOMP

ICOMP

TERM

SNS

TPWM Regulator timebase input

BTST Battery test output

LCOM Common LED output

System ground

5.0V

10% power

MOD Modulation control

output

LED

/ Charge status output 1/

CSEL Charge sense select

input

LED

/ Charge status output 2/

DSEL Display select input

Pin Connections

Pin Names

SLUS064–OCTOBER 1998 B

Lithium Ion Charge Management IC

with Integrated Switching Controller

bq2954

Summary of content (23 pages)

PAGE 1
bq2954 Lithium Ion Charge Management IC with Integrated Switching Controller Features General Description ➤ Safe charge of Li-Ion battery packs The bq2954 Li-Ion Charge-Management IC uses a flexible pulse-width modulation regulator to control voltage and current during charging. The regulator frequency is set by an external capacitor for design flexibility. The switch-mode design minimizes power dissipation.
PAGE 2
bq2954 TPWM Pin Descriptions TM Uses an external timing capacitor to ground to set the pulse-width modulation (PWM) frequency. See Equation 7. Time-out programming input Sets the maximum charge time. The resistor and capacitor values are determined using Equation 5. Figure 10 shows the resistor/capacitor connection.
PAGE 3
bq2954 VCC TM Power-On Reset MTO Timer ITERM TPWM Oscillator DSEL CSEL VSS Charge Control State Machine Voltage Reference LED1 LED2 BTST CHG Display Control TS VCOMP LCOM BAT PWM Regulator SNS ICOMP MOD BD2954.eps Figure 1. Functional Block Diagram Functional Description Charge Qualification The bq2954 functional operation is described in terms of the following (Figure 1): The bq2954 starts a charge cycle when power is applied while a battery is present or when a battery is inserted.
PAGE 4
bq2954 Volt Fault: When VBAT > VHCO Time Fault: When T = MTO/4 in State S02 or T = MTO in S03a Hold Time: A VHCO Fault or State charge held off for 0.740s to 1.12s VCC "Up" Power-On Reset Mod = 0 No Action Latch DSEL/CSEL Inputs Battery Removal VBAT < 0.8V Reset Faults Latch DSEL/CSEL Inputs Temp Not Valid 0.8V > VBAT > VHCO Hold Time Hold-off Faults CHG = 0 Battst = 1 VBAT< VRCHG QUALIFICATION Fault CHG = 0 S01 Temp Valid VHCO < VBAT >0.
PAGE 5
bq2954 R2 D4 8-24VDC ±10% VDC R1 C10 47uF 25V R4 10K U2 ZMR500 G OUT IN N D C3 1uF 25V L2 4.7K Q1 FMMT3906 B130DI D5 B130DI 1K 5V R5 10K C2 1uF BAT+ 47uH Q5 FZT789A Q2 FMMt3904 L1 10 uH D1 1N4148 Q3 FMMT451 C11 10uF 20V PCS4106 R14 RB1 5V R15 RB2 R6 10K R9 220 BATR10 62K D2 GRREN 5V R7 1K U1 0.1 uF R13 1K C8 1000pF C4 0.1 uF C6 R8 0.25 5% 0.
PAGE 6
bq2954 Table 1.
PAGE 7
bq2954 Table 2.
PAGE 8
bq2954 Table 3. Abnormal Condition VBAT Battery Absent IBAT Qualification Abnormal Battery VREG IMAX VMIN ICOND IMIN Time Mode 1 (DSEL = 0) Mode 2 (DSEL = 1) Mode 3 (DSEL = F) CHG BTST LED1 LED2 LED1 LED2 LED1 LED2 Low Low Low Low Low Low Low High tQT High Low High Low High Low High Low Flash Low Low Low Low Low Low Low GR295403.eps Table 4.
PAGE 9
bq2954 Battery insertion is detected within 500ms. Transition to the fast-charge phase, however, will not occur for time tHO (approximately one second), even if voltage qualification VMIN is reached. This delay prevents a voltage spike at the BAT input from causing premature entry into the fast-charge phase. It also creates a delay in detection of battery removal if the battery is removed during this hold-off period. minimum current threshold, IMIN.
PAGE 10
bq2954 VCC LED2/DSEL LED1 VCC 10K 1K 16 LED2/DSEL 15 LED1 10K 1K 16 15 1K 1K VCC VSS 6 LCOM 13 VCC 12 VSS 6 11 LCOM bq2954 13 12 10K 11 bq2954 VSS VSS Low-Side Sense Mode High-Side Sense Mode FGbq295402LS.eps FGbq295402HS.eps Figure 4. Configured Display Mode (Low-Side Sense) VCC Figure 5.
PAGE 11
bq2954 VCC VCC RT1 bq2954 LPD1 13 12 bq2954 LPD1 RT2 VSS SNS TS 13 NTC Thermistor RT t VCC 12 BAT - 7 RT1 NTC Thermistor VCC RT2 VSS SNS 7 8 TS 8 RCSEL BAT - RSNS VSS VSS Low-Side Sense Mode High-Side Sense Mode FGbq295404LS.eps FGbq295404HS.eps Figure 8. Low-Side Temperature Sensing Figure 9. High-Side Temperature Sensing Disabling Temperature Sensing VCC Temperature sensing can be disabled by placing a 10kΩ resistor between TS and BAT- and a 10kΩ resistor between TS and VCC.
PAGE 12
bq2954 Where C is in Farads and the frequency is in Hz. A typical switching rate is 100kHz, implying CPWM = 0.001µF. MOD pulse width is modulated between 0 and 80% of the switching period. Charge Regulation The bq2954 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.
PAGE 13
bq2954 Absolute Maximum Ratings Symbol Parameter Minimum Maximum Unit Notes 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 -20 +70 °C Commercial TOPR Operating ambient temperature -40 +85 °C Industrial “N” -55 +125 °C - +260 °C TSTG Storage temperature TSOLDER Soldering temperature Note: Permanent device damage may occur if Absolute Maximum Ratings are exceeded.
PAGE 14
bq2954 Recommended DC Operating Conditions (TA = TOPR) Symbol Parameter VCC Supply voltage VTEMP Minimum Typical Maximum Unit Notes 4.5 5.0 5.5 V TS voltage potential 0 - VCC V VBAT BAT voltage potential 0 - VCC V ICC Supply current - 2 4 mA Outputs unloaded DSEL tri-state open detection -2 - 2 µA Note VTS - VSNS IIZ ITERM tri-state open detection 2 µA VIH Logic input high VCC - 0.3 - - V DSEL, ITERM VIL Logic input low - - VSS + 0.
PAGE 15
bq2954 Impedance (TA = TOPR; VCC = 5V ± 10%) 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, CSEL RPROG2 Pull-up or pull-down resistor value - - 3 kΩ ITERM RMTO Charge timer resistor 20 - 480 kΩ Minimum Typical Maximum Unit Timing (TA = TOPR; VCC
PAGE 16
bq2954 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.
PAGE 17
bq2954 Data Sheet Revision History Change No. Page No. 1 All Note: Description of Change “Final” changes from “Preliminary” version Change 1 = Oct. 1998 B changes from Nov. 1997 “Preliminary.
PAGE 18
IMPORTANT NOTICE Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete.
PAGE 19
PACKAGE OPTION ADDENDUM www.ti.
PAGE 20
PACKAGE OPTION ADDENDUM www.ti.com 2-Jun-2013 Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties.
PAGE 21
PACKAGE MATERIALS INFORMATION www.ti.com 26-Jan-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device BQ2954SNTR Package Package Pins Type Drawing SOIC D 16 SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) 2500 330.0 16.4 Pack Materials-Page 1 6.5 B0 (mm) K0 (mm) P1 (mm) 10.3 2.1 8.0 W Pin1 (mm) Quadrant 16.
PAGE 22
PACKAGE MATERIALS INFORMATION www.ti.com 26-Jan-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) BQ2954SNTR SOIC D 16 2500 367.0 367.0 38.
PAGE 23
IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.