The bq24157 is a compact, flexible, high-efficiency, USB-friendly switch-mode charge
management device for single-cell Li-ion and Li-polymer batteries used in a wide range of portable
applications. The charge parameters can be programmed through an I2C
interface. The IC integrates a synchronous PWM controller, power MOSFETs, input current sensing,
high-accuracy current and voltage regulation, and charge termination, into a small WCSP
package.
The IC charges the battery in three phases: conditioning, constant current and constant
voltage. The input current is automatically limited to the value set by the host. Charge is
terminated based on battery voltage and user-selectable minimum current level. A safety timer with
reset control provides a safety backup for I2C interface. During normal
operation, The IC automatically restarts the charge cycle if the battery voltage falls below an
internal threshold and automatically enters sleep mode or high impedance mode when the input supply
is removed. The charge status can be reported to the host using the I2C
interface. During the charging process, the IC monitors its junction temperature
(TJ) and reduces the charge current once TJ increases
to about 125°C. To support USB OTG device, bq24157 can provide VBUS (5.05 V) by boosting the
battery voltage. The IC is available in 20-pin WCSP package.
The bq24157 is a compact, flexible, high-efficiency, USB-friendly switch-mode charge
management device for single-cell Li-ion and Li-polymer batteries used in a wide range of portable
applications. The charge parameters can be programmed through an I2C
interface. The IC integrates a synchronous PWM controller, power MOSFETs, input current sensing,
high-accuracy current and voltage regulation, and charge termination, into a small WCSP
package.
The IC charges the battery in three phases: conditioning, constant current and constant
voltage. The input current is automatically limited to the value set by the host. Charge is
terminated based on battery voltage and user-selectable minimum current level. A safety timer with
reset control provides a safety backup for I2C interface. During normal
operation, The IC automatically restarts the charge cycle if the battery voltage falls below an
internal threshold and automatically enters sleep mode or high impedance mode when the input supply
is removed. The charge status can be reported to the host using the I2C
interface. During the charging process, the IC monitors its junction temperature
(TJ) and reduces the charge current once TJ increases
to about 125°C. To support USB OTG device, bq24157 can provide VBUS (5.05 V) by boosting the
battery voltage. The IC is available in 20-pin WCSP package.