The bq25601 device is a highly-integrated 3-A switch-mode battery charge management and system power path managementdevice for single cell Li-Ion and Li-polymer battery. The low impedance power path optimizesswitch-mode operation efficiency, reduces battery charging time and extends battery life duringdischarging phase. The I2C serialinterface with charging and system settings makes the device a truly flexiblesolution.
The bq25601 is a highly-integrated 3.0-A switch-mode battery charge management and system power pathmanagement device for single cell Li-Ion and Li-polymer battery. It features fast charging withhigh input voltage support for a wide range of smartphones, tablets and portable devices. Itslow impedance power path optimizes switch-mode operation efficiency, reduces battery charging timeand extends battery life during discharging phase. Its input voltage and current regulation deliver maximum charging power tobattery. The solution is highly integrated with input reverse-blocking FET (RBFET, Q1), high-sideswitching FET (HSFET, Q2), low-side switching FET (LSFET, Q3), and battery FET (BATFET, Q4) betweensystem and battery. It also integrates the bootstrap diode for the high-side gate drive forsimplified system design. TheI2C serial interface with charging and system settings makes the devicea truly flexible solution.
The device supports a wide range of input sources, including standard USB host port, USBcharging port, and USB compliant high voltage adapter. The device sets default input currentlimit based on the built-in USB interface. To setthe default input current limit, the device takes the result from detection circuit in the system, such as USB PHY device.The device is compliant with USB 2.0 and USB 3.0 power spec with input current and voltageregulation. The device also meets USB On-the-Go (OTG) operation power rating specification bysupplying 5.15 V on VBUS with constant current limit up to 1.2A.
The power path management regulates the system slightly above battery voltage but doesnot drop below 3.5 V minimum system voltage(programmable). With this feature, the system maintains operation even when the battery iscompletely depleted or removed. When the input current limit or voltage limit is reached, the powerpath management automatically reduces the charge current to zero. As the system load continues toincrease, the power path discharges the battery until the system power requirement is met. ThisSupplement Mode prevents overloading the input source.
The device initiates and completes a charging cycle without software control. It sensesthe battery voltage and charges the battery in three phases: pre-conditioning, constant current andconstant voltage. At the end of the charging cycle, the charger automatically terminates when thecharge current is below a preset limit and the battery voltage is higher than recharge threshold.If the fully charged battery falls below the recharge threshold, the charger automatically startsanother charging cycle.
The charger provides various safety features for battery charging and system operations,including battery negative temperature coefficient thermistor monitoring, charging safety timer andovervoltage and overcurrent protections. The thermal regulation reduces charge current when thejunction temperature exceeds 110°C (programmable).The STAT output reports the charging status and any fault conditions. Other safety features includebattery temperature sensing for charge and boost mode, thermal regulation and thermal shutdown andinput UVLO and overvoltage protection. The VBUS_GD bitindicates if a good power source is present. The INT output Immediatelynotifies host when fault occurs.
The device also provides QON pinfor BATFET enable and reset control to exit low power ship mode or full system resetfunction.
The device is available in 24-pin, 4 mm × 4 mm x 0.75 mm thin WQFN package.