bq24108

Features:

· Ideal For Highly Efficient Charger Designs For Single-, Two- or Three-Cell Li-Ion and Li-Polymer Battery Packs
· Integrated Synchronous Fixed-Frequency PWM Controller Operating at 1.1 MHz With 0% to 100% Duty Cycle
· Integrated Power FETs For Up To 2-A Charge Rate
· High-Accuracy Voltage and Current Regulation
· Available In Both Stand-Alone (Built-In Charge Management and Control) and System-Controlled (Under System Command) Versions
· Status Outputs For LED or Host Processor Interface Indicates Charge-In-Progress, Charge Completion, Fault, and AC-Adapter Present Conditions
· 20-V Maximum Voltage Rating on IN and OUT Pins
· High-Side Current Sensing
· Optional Battery Temperature Monitoring
· Automatic Sleep Mode for Low Power Consumption
· System-Controlled Version Can Be Used In NiMH and NiCd Applications
· Uses Ceramic Capacitors
· Reverse Leakage Protection Prevents Battery Drainage
· Thermal Shutdown and Protection
· Built-In Battery Detection


Application

· Handheld Products
· Portable Media Players
· Industrial and Medical Equipment
· Portable Equipment


Specifications

		UNIT
Supply voltage range (with respect to VSS)	IN, VCC	20 V
Input voltage range (with respect to VSS and PGND)	STAT1, STAT2, PG, CE, CELLS, SNS, BAT	0.3 V to 20 V
	OUT	0.7 V to 20 V
	CMODE, TS, TTC	7 V
	VTSB	3.6 V
	ISET1, ISET2	3.3 V
Voltage difference between SNS and BAT inputs (VSNS - VBAT)		±1 V
Output sink	STAT1, STAT2, PG	10 mA
Output current (average)	OUT	2.2 A
TA Operating free-air temperature range		40°C to 85°C
TJ Junction temperature range		40°C to 125°C
Tstg Storage temperature		65°C to 150°C
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds		300°C

Description

The bqSWITCHER™ series are highly integrated Li-ion and Li-polymer switch-mode charge management devices targeted at a wide range of portable applications. The bqSWITCHER™ series offers integrated synchronous PWM controller and power FETs, high-accuracy current and voltage regulation, charge preconditioning, charge status, and charge termination, in a small, thermally enhanced QFN package. The system-controlled version provides additional inputs for full charge management under system control.

The bqSWITCHER charges the battery of bq24108 in three phases: conditioning, constant current, and constant voltage. Charge is terminated based on userselectable minimum current level. A programmable charge timer provides a safety backup for charge termination. The bqSWITCHER automatically restarts the charge cycle if the battery voltage falls below an internal threshold. The bqSWITCHER automatically enters sleep mode when VCC supply is removed.