Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsPMICsPMIC - battery management Charge management NiCd, NiMH SOIC 8 Surface-mount

SNS

LED

BAT

MOD

bq24400

www.ti.com

SLUS498A –SEPTEMBER 2001–REVISED FEBRUARY 2010

Programmable NiCd/NiMH Fast-Charge Management IC

Check for Samples: bq24400

FEATURES

GENERAL DESCRIPTION

• Safe Management of Fast Charge for NiCd and

NiMH Battery Packs

The bq24400 is a programmable, monolithic IC for

fast-charge management of nickel cadmium (NiCd)

• High-Frequency Switching Controller for

and nickel metal-hydride (NiMH) in single or multi-cell

Efficient and Simple Charger Design

applications.

• Pre-Charge Qualification for Detecting

The bq24400 provides these charge termination

Shorted, Damaged, or Overheated Cells

criteria:

• Fast-Charge Termination by Peak Voltage

• Peak voltage, PVD

(PVD), Maximum Temperature, and Maximum

• Maximum temperature

Charge Time

• Maximum charge time

• Selectable Top-Off Mode for Achieving

Maximum Capacity in NiMH Batteries

For safety, the bq24400 inhibits fast charge until the

battery voltage and temperature are within

• Programmable Trickle-Charge Mode for

user-defined limits. If the battery voltage is below the

Reviving Deeply Discharged Batteries and for

low-voltage threshold, the bq24400 uses

Postcharge Maintenance

trickle-charge to condition the battery. For NiMH

• Built-in Battery Removal and Insertion

batteries, the bq24400 provides an optional top-off

Detection

charge to maximize the battery capacity.

• Sleep Mode for Low Power Consumption

The integrated high-speed comparator allows the

bq24400 to be the basis for a complete,

APPLICATIONS

high-efficiency battery charger circuit for nickel-based

• Nickel Charger

chemistries.

• High-Power, Multi-Cell Charger

spacer between para and illustration

8-Pin DIP or Narrow SOIC or TSSOP Pin Names

SNS Current-sense input

System ground

LED Charge-status output

BAT Battery-voltage input

TS Temperature-sense input

RC Timer-program input

Supply-voltage input

MOD Modulation-control output

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.

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.

Summary of content (25 pages)

PAGE 1
bq24400 www.ti.
PAGE 2
bq24400 SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 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.
PAGE 3
bq24400 www.ti.com SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 FUNCTIONAL DESCRIPTION The bq24400 is a versatile, NiCd and NiMH battery charge control device. See Figure 1 for a functional block diagram and Figure 2 for a state diagram. TS Voltage Reference BAT OSC Voltage Comparators 3x ADC PVD ALU Clock Phase Generator Timer Charge Control LED Voltage Comparators MOD RC Internal OSC SNS VCC VSS Figure 1.
PAGE 4
bq24400 SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 www.ti.com VCC Reset or Battery Replacement at any time 4.0 V < VCC < 6.0 V Charge Initialization VBAT < VSLP Battery Voltage (Voltage at BAT pin checked continuously. PVD checked at rate of MTO/128.
PAGE 5
bq24400 www.ti.com SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 ABSOLUTE MAXIMUM RATINGS (1) VALUE UNIT –0.3 to 7 V –0.3 to VCC V Operating ambient temperature –20 to 70 °C Storage temperature –40 to 125 °C 260 °C VCC VCC relative to VSS VT DC voltage applied on any pin, relative to VSS TOPR TSTG TSOLDER Soldering temperature (10 s max.) (1) Permanent device damage may occur if Absolute Maximum Ratings are exceeded.
PAGE 6
bq24400 SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 www.ti.com Initiation and Charge Qualification The bq24400 initiates a charge cycle when it detects • Application of power to VCC • Battery replacement • Exit from sleep mode Immediately following initiation, the IC enters a charge-qualification mode. The bq24400 charge qualification is based on battery voltage and temperature.
PAGE 7
bq24400 www.ti.com SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 Maximum Charge Time The bq24400 sets the maximum charge-time through the RC pin. With the proper selection of external resistor and capacitor values, various time-out values may be achieved. If the timer expires while still in fast charge, the bq24400 proceeds to top-off charge (if top-off is enabled) or trickle maintenance charge. If top-off is enabled, the timer is reset on the completion of fast charge before beginning top-off charge.
PAGE 8
bq24400 SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 www.ti.com disabled. When the voltage at the TS pin is lower than VTCO, the bq24400 terminates fast charge, moves to the charge suspended state, and turns off the LED. When VTS rises above VHTF, the bq24400 will resume charging in the trickle maintenance charge state, per Figure 2. In fast charge, when the voltage on the TS pin is higher than VLTF, the charger enters the battery conditioning state, as described in the previous section.
PAGE 9
bq24400 www.ti.com SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 Pulsewidth - ms Following top-off, the bq24400 trickle-charges the battery by enabling the MOD pin to charge at a rate of once every 1.0 second. The trickle pulse-width is user-selectable and is set by the value of the resistor RMTO, connected between the RC pin and VSS. Figure 6 shows the relationship between the trickle pulse-width and the value of RMTO. The typical tolerance of the pulsewidth below 150kΩ is ±10%.
PAGE 10
bq24400 SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 www.ti.com Both top-off and trickle maintenance charge are terminated and the pack never receives any more charge (until a charge initialization occurs) if the voltage on the BAT pin reaches VMCV. During trickle maintenance charge, charging is suspended if VTS < VHTF. It resumes when VTS > VHTF. The bq24400 is designed to remain in trickle maintenance charge forever (excluding the two faults just mentioned) in order to keep the Nickel pack full.
PAGE 11
bq24400 www.ti.com SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 Q1 FMMT718 D4 DC+ S1A D3 MMSD914LT C6 47 mF D5 MMSD914LT L1 BAT+ 47 mH Q2 MMBT3904LT1 D2 ZHCS1000 R12 120 W C9 R10 1 KW 1000 PF Q3 MMBT3904LT1 VCC R2 2 KW D6 BZT52-C5V1 C3 10 mF R11 220 W C7 C4 4.7 PF 0.0022 mF R1 D1 RED C2 0.1 mF U1 1 SNS 2 VSS 3 LED 4 BAT C8 0.33 mF R4 12.4 KW R6 210 KW C5 10 mF 100 KW 8 7 6 5 MOD VCC RC TS THERM bq24400 C1 0.1 mF R8 6.81 KW R5 20 KW BATR7 105 KW R13 1.1 KW R3 0.
PAGE 12
bq24400 SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 www.ti.com 180 160 fs - Switching Frequency - kHz Rf = 748W 140 120 100 80 60 40 20 0 220 720 1220 1720 2220 2720 3220 3720 4220 Cf - pF Figure 9. Switching Frequency vs Capacitance 210 fs - Switching Frequency - kHz 190 Cf = 1000pF 170 150 130 110 90 70 50 200 300 400 500 600 700 800 900 1000 1100 1200 Rf - W Figure 10.
PAGE 13
bq24400 www.ti.com SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 TEMPERATURE MONITORING The bq24400 measures the temperature by the voltage at the TS pin. This voltage is typically generated by a negative-temperature-coefficient thermistor. The bq24400 compares this voltage against its internal threshold voltages to determine if charging is safe. These thresholds are the following: • High-temperature cutoff voltage: VTCO = 0.225 × VCC.
PAGE 14
bq24400 SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 www.ti.com Charge Status Display The charge status is indicated by open-drain output LED. Table 5 summarizes the display output of the bq24400. A temperature fault or timer expiring changes the charge state immediately (according to Figure 2) and will thus change the LED status immediately and accordingly. Table 5.
PAGE 15
bq24400 www.ti.com SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 TYPICAL CHARACTERISTICS CH1 = RC pin, 2V/div CH1 = RC pin, 2V/div 1 CH2 = MOD pin, 5V/div CH2 = MOD pin, 5V/div Voltage - V Voltage - V 2 CH3 = VO, 5V/div 2 CH3 = VI, 5V/div 3 CH4 = LED pin, 5V/div 1 CH4 = LED pin, 5V/div 4 3 4 Time - 0.2s/div Time - 0.2s/div Figure 11. bq24400 Start-up on Battery Insertion Figure 12.
PAGE 16
bq24400 SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 www.ti.com TYPICAL CHARACTERISTICS (continued) CH1 = VO, 5V/div 1 CH2 = RC pin, 1V/div CH1 = SNS pin, 20mV/div CH3 = MOD pin, 5V/div 2 Voltage - V Voltage - V 1 CH2 = MOD pin, 5V/div 3 2 4 CH4 = LED pin, 1V/div Time - 2ms/div Time - 10ms/div Figure 15. bq24400 in Fast Charge Figure 16.
PAGE 17
bq24400 www.ti.com SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010 REVISION HISTORY Changes from Revision September 2001 (*) to Revision A • Page Changed the data sheet format. The data sheet was originally from Benchmark Products. In revision A, the data sheet was converted to the TI format, and a re-write of the data sheet was implemented ..................................................
PAGE 18
PACKAGE OPTION ADDENDUM www.ti.
PAGE 19
PACKAGE OPTION ADDENDUM www.ti.com 10-Jun-2014 (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line.
PAGE 20
PACKAGE MATERIALS INFORMATION www.ti.com 11-Jun-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant BQ24400DR SOIC D 8 2500 330.0 12.4 6.4 5.2 2.1 8.0 12.0 Q1 BQ24400PWR TSSOP PW 8 2000 330.0 12.4 7.0 3.6 1.6 8.0 12.
PAGE 21
PACKAGE MATERIALS INFORMATION www.ti.com 11-Jun-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) BQ24400DR SOIC D 8 2500 367.0 367.0 35.0 BQ24400PWR TSSOP PW 8 2000 367.0 367.0 35.
PAGE 22
PAGE 23
PAGE 24
PAGE 25
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.