bq24747
www.ti.com ............................................................................................................................................................................................. SLUS988 –OCTOBER 2009
SMBus-Controlled Level 2 Multi-Chemistry Battery Charger With Input
Current Detect Comparator and Charge Enable Pin
Check for Samples :bq24747
1
FEATURES
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< 1 mA Input DCIN Current with Adapter
Present and Charge Disabled
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NMOS-NMOS Synchronous Buck Converter
with 300 kHz Frequency and >95% Efficiency
28-pin, 5x5-mm2 QFN Package
30-ns Minimum Driver Dead-time and 99.5%
Maximum Effective Duty Cycle
APPLICATIONS
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Notebook and Ultra-Mobile Computers
Portable Data-Capture Terminals
Portable Printers
Medical Diagnostics Equipment
Battery Bay Chargers
High-Accuracy Voltage and Current Regulation
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±0.5% Charge Voltage Accuracy
±3% Charge Current Accuracy
±3% Adapter Current Accuracy
±2% Input Current Sense Amp Accuracy
Battery Back-up Systems
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Integration
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Input Current Comparator, With Adjustable
DESCRIPTION
Threshold and Hysteresis
The bq24747 is
a high-efficiency, synchronous
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Internal Soft-Start
battery charger with an integrated input-current
comparator, offering low component count for
space-constrained, multi-chemistry battery-charging
applications. The input-current, charge-current, and
charge-voltage DACs allow very high regulation
accuracies that can be easily programmed by the
system power-management microcontroller using the
SMBus interface. The bq24747 charges two, three, or
four series Li+ cells, and is available in a 28-pin, 5x5
mm2 QFN package.
Safety
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Input Overvoltage Protection (OVP)
Dynamic Power Management (DPM)
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Up to 19.2 V Battery Voltage
7 V–24 V AC/DC-Adapter Operating Range
Simplified SMBus Control Interface
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Charge Voltage DAC (1.024 V–19.2 V)
Charge Current DAC (128 mA–8.064 A)
Adapter Current Limit DPM DAC (256
mA–11.008 A)
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28
27
26
25
24
22
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Status and Monitoring Outputs
ICREF
ACIN
VDDP
LGATE
PGND
1
2
3
4
21
20
19
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AC/DC Adapter Present with Adjustable
Voltage Threshold
Input Current Comparator, With Adjustable
Threshold and Hysteresis
VREF
bq24747
28 LD QFN
TOP VIEW
CSOP
CSON
18
17
EAO
EAI
Current Sense Amplifier for Current Drawn
From Input Source
5
6
7
FBO
CE
NC
16
15
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Charge Any Battery Chemistry: Li+, NiCd,
NiMH, Lead Acid, etc.
VFB
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Charge Enable Pin
8
9
10
11
12
13
14
< 10-μBattery Current with Adapter Removed
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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.
Copyright © 2009, Texas Instruments Incorporated