BQ24735_17 Datasheet, PDF (1/46 Pages) Texas Instruments – 1- to 4-Cell Li+ Battery SMBus Charge Controller for Supporting Turbo Boost Mode With N-Channel Power MOSFET Selector

Product
Folder
Sample &
Buy
Technical
Documents
Tools &
Software
Support &
Community
bq24735
SLUSAK9B – SEPTEMBER 2011 – REVISED APRIL 2015
bq24735 1- to 4-Cell Li+ Battery SMBus Charge Controller for Supporting Turbo
Boost Mode With N-Channel Power MOSFET Selector
1 Features
•1 Adapter and Battery Provide Power to System
Together to Support Intel^® CPU Turbo Boost
Mode
• SMBus Host-Controlled NMOS-NMOS
Synchronous Buck Converter With Programmable
615-, 750-, and 885-kHz Switching Frequencies
• Automatic N-Channel MOSFET Selection of
System Power Source From Adapter or Battery
Driven by Internal Charge Pumps
• Enhanced Safety Features for Overvoltage
Protection, Overcurrent Protection, Battery,
Inductor and MOSFET Short-Circuit Protection
• Programmable Input Current, Charge Voltage,
Charge Current Limits
– ±0.5% Charge Voltage Accuracy up to 19.2 V
– ±3% Charge Current Accuracy up to 8.128 A
– ±3% Input Current Accuracy up to 8.064 A
– ±2% 20× Adapter Current or Charge Current
Amplifier Output Accuracy
• Programmable Battery Depletion Threshold, and
Battery LEARN Function
• Programmable Adapter Detection and Indicator
• Integrated Loop Compensation and Soft Start
• Real-Time System Control on ILIM Pin to Limit
Charge Current
• AC Adapter Operating Range: 4.5 V to 24 V
• 5-µA Off-State Battery Discharge Current
• 0.65 mA (0.8 mA Max) Adapter Standby
Quiescent Current
2 Applications
• Portable Notebook Computers, UMPC, Ultra-Thin
Notebooks, and Netbooks
• Handheld Terminals
• Industrial and Medical Equipment
• Portable Equipment
3 Description
The bq24735 device is a high-efficiency, synchronous
battery charger, offering low component count for
space-constrained, multichemistry battery charging
applications. The bq24735 device supports turbo
boost by allowing battery discharge energy to the
system when system power demand is temporarily
higher than the adapter maximum power level so the
adapter will not crash.
The bq24735 device uses two charge pumps to
separately drive N-channel MOSFETs (ACFET,
RBFET, and BATFET) for automatic system power
source selection.
SMBus controlled input current, charge current, and
charge voltage digital-to-analog converters (DACs)
allow for very high-regulation accuracies that can be
easily programmed by the system power
management microcontroller.
Device Information⁽¹⁾
PART NUMBER
PACKAGE
BODY SIZE (NOM)
bq24735
VQFN (20)
3.50 mm × 3.50 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Simplified Application Diagram
Adapter
4.5 to 24 V
N-FET Driver
R_AC
Enhanced Safety:
OCP, OVP,
FET Short
Adapter Detection
bq24735
SMBus Controls V and I
with high accuracy
SMBus
Hybrid Power
Boost Charge
Controller
HOST
SYS
N-FET Driver
Battery
Pack
R_SR
1S-4S
Integration: Loop Compensation;
Soft-Start Comparator
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.