 

SLUS553D − MAY 2003 − REVISED JULY 2005

   

   

    

 

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FEATURES

Dynamic Power Management, DPM

Minimizes Battery Charge Time

D Integrated Selector Supports Battery

Conditioning and Smart Battery Learn Cycle

D Zero Volt Operation

D Selector Feedback Circuit Ensures

Break-Before-Make Transition

D ±0.4% Charge Voltage Accuracy, Suitable for

Charging Li-Ion Cells

D ±4% Charge Current Accuracy

D 300-kHz Integrated PWM Controller for

High-Efficiency Buck Regulation

D Depleted Battery Detection and Indication to

Protect Battery From Over Discharge

D 20-µA Sleep Mode Current for Low Battery

Drain

D 24-Pin TSSOP Package and 5 mm × 5 mm

QFN package (bq24703 only)

DESCRIPTION

The bq24702/bq24703 is a highly integrated battery

charge controller and selector tailored for notebook and

sub-notebook PC applications.

The bq24702/bq24703 uses dynamic power

management (DPM) to minimize battery charge time by

maximizing use of available wall-adapter power. This is

achieved by dynamically adjusting the battery charge

current based on the total system (adapter) current.

The bq24702/bq24703 uses a fixed frequency, pulse

width modulator (PWM) to accurately control battery

charge current and voltage. Charge current limits can

be programmed from a keyboard controller DAC or by

external resistor dividers from the precision 5-V, ±0.6%,

externally bypassed voltage reference (VREF),

supplied by the bq24702/bq24703.

ACDET

ACPRES

ACSEL

BATDEP

SRSET

ACSET

VREF

ENABLE

BATSET

COMP

ACN

ACP

ACDRV

BATDRV

VCC

PWM

VHSP

ALARM

GND

SRP

SRN

IBAT

BATP

bq24702, bq24703

PW PACKAGE

(TOP VIEW)

ACSEL

ACPRES

ACDET

ACDRV

BATDRV

VCC

ACN

ACP

BATP

IBAT

BATDEP

SRSET

ACSET

VREF

ENABLE

BATSET

COMP

PWM

VHSP

ALARM

GND

SRP

SRN

bq24703

RHD PACKAGE

(BOTTOM VIEW)

NC − No internal connection

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.

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 

SLUS553D − MAY 2003 − REVISED JULY 2005

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DESCRIPTION (continued)

The battery voltage limit can be programmed by using the internal 1.196-V, ±0.5% precision reference, making it

suitable for the critical charging demands of lithium-ion cells. Also, the bq24702/bq24703 provides an option to

override the precision reference and drive the error amplifier either directly from an external reference or from a

resistor divider off the 5 V supplied by the integrated circuit.

The selector function allows the manual selection of the system power source, battery or wall-adapter power. The

bq24702/bq24703 supports battery-conditioning and battery-learn cycles through the ACSEL function. The ACSEL

function allows manual selection of the battery or wall power as the main system power. It also provides autonomous

switching to the remaining source (battery or ac power) should the selected system power source terminate (refer

to Table 1 for the differences between the bq24702 and the bq24703). The bq24702/bq24703 also provides an alarm

function to indicate a depleted battery condition.

The bq24702/bq24703 PWM controller is ideally suited for operation in a buck converter for applications when the

wall-adapter voltage is greater than the battery voltage.

DISSIPATION RATINGS

0.20

0.40

0.60

0.80

1.20

1.40

1.60

25 50 70 85

MAX Pd (W) @ 500 LFM

MAX Pd (W) @ 250 LFM

MAX Pd (W) @ 150 LFM

MAX Pd (W) @ 0 LFM

= 89.37 C/W @ 0 LFM,

= 77.98 C/W @ 150 LFM,

= 73.93 C/W @ 250 LFM,

= 68.23 C/W @ 500 LFM

Maximum Power Dissipation (High K Board) − W

MAXIMUM POWER DISSIPATION

(HIGH K BOARD)

FREE-AIR TEMPERATURE

− Free-Air Temperature − °C

0.20

0.40

0.60

0.80

1.20

1.40

25 50 70 85

MAX Pd (W) @ 500 LFM

MAX Pd (W) @ 250 LFM

MAX Pd (W) @ 150 LFM

MAX Pd (W) @ 0 LFM

= 150.17 C/W @ 0 LFM,

= 110.95 C/W @ 150 LFM,

= 99.81 C/W @ 250 LFM,

= 86.03 C/W @ 500 LFM

Maximum Power Dissipation (Low K Board) − W

MAXIMUM POWER DISSIPATION

(LOW K BOARD)

FREE-AIR TEMPERATURE

− Free-Air Temperature − °C

†

The JEDEC low K (1s) board design used to derive this data was a 3-inch x 3-inch, two layer board with 2 ounce copper traces on top of the board.

‡

The JEDEC high K (1s) board design used to derive this data was a 3-inch x 3-inch, multilayer board with 1 ounce internal power and ground

planes and 2 ounce copper traces on top and bottom of the board.

 

SLUS553D − MAY 2003 − REVISED JULY 2005

www.ti.com

Table 1. Available Options

CONDITION

SELECTOR OPERATION

CONDITION

−20°C ≤ T

≤ 125°C

bq24702PW bq24703RHD

Battery as Power Source

Battery removal Automatically selects ac + alarm Automatically selects ac + alarm

Battery reinserted Selection based on selector inputs

Adapter latched until adapter is removed or ac select

toggles.

AC as Power Source

AC removal Automatically selects battery Automatically selects battery

AC reinserted Selection based on selector inputs Selection based on selector inputs

Depleted Battery Condition

Battery as power source Sends ALARM signal

Automatically selects ac

Sends ALARM signal

AC as power source Sends ALARM signal Sends ALARM signal

ALARM Signal Active

Depleted battery condition Depleted battery condition

When selector input is not equal to selector

output (single pulse alarm)

ABSOLUTE MAXIMUM RATINGS OVER OPERATING FREE-AIR TEMPERATURE

(unless otherwise noted)

Ĕ}

Supply voltage range: VCC −0.3 V to 30 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Battery voltage range: SRP, SRN −0.3 V to 30 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Input voltage: ACN, ACP −0.3 V to 30 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Virtual junction temperature range, T

−40°C to 125°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum source/sink current VHSP 50 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum ramp rate for V

10 V/ µs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum sink current ACPRES, COMP, ALARM 2.5 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum ramp rate for V

(BAT)

10 V/ µs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum source/sink current BATDRV

10 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum source/sink current ACDRV

10 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum source/sink current PWM

50 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum source/sink current pulsed ACDRV

, (10-µs rise time, 10-µs fall time, 1-ms pulse width, single pulse) 50 mA

Maximum source current VREF 30 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum source current SRP 100 mA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum difference voltage SRP − SRN 30 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Storage temperature range T

stg

−65°C to 150°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Lead temperature (soldering, 10 seconds) 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.

‡

All voltages are with respect to ground. Currents are positive into and negative out of the specified terminals. Consult the Packaging section of

the data book for thermal limitations and considerations of the package.

Part #	BQ24702PWR
Description	IC BATT CHARGER CTRLR 24-TSSOP
Category	IC
Availability	In Stock
Qty	88

Qty	Price
1 - 18	$2.81248
19 - 36	$2.23720
37 - 55	$2.10936
56 - 73	$1.96022
74 +	$1.74715

Manufacturer	Available	Qty
Texas Instruments	Freelance Stock: 39 Ships Immediately
Texas Instruments Date Code: 1023	Freelance Stock: 49 Ships Immediately

BQ24702PWR

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