ZHCSGD8A May 2017 – May 2018
PRODUCTION DATA.
The bq25703A is a buck boost NVDC (narrow voltage DC) charge controller for multi-chemistry portable applications such as notebook, detachable, ultrabook, tablet and other mobile devices with rechargeable batteries. It provides seamless transition between converter operation modes (buck, boost, or buck boost), fast transient response, and high light load efficiency.
The bq25703A supports wide range of power sources, including USB PD ports, legacy USB ports, traditional AC-DC adapters, etc. It takes input voltage from 3.5 V to 24 V, and charges battery of 1-4 series. It also supports USB On-The-Go (OTG) to provide 4.48V to 20.8V output at USB port.
The bq25703A features Dynamic Power Management (DPM) to limit the input power and avoid AC adapter overloading. During battery charging, as the system power increases, the charging current will reduce to maintain total input current below adapter rating. If system power demand temporarily exceeds adapter rating, the bq25703A supports NVDC architecture to allow battery discharge energy to supplement system power. For details, refer to System Voltage Regulation section.
In order to be compliant with an Intel IMVP8 compliant system, the bq25703A includes PSYS function to monitor the total platform power from adapter and battery. Besides PSYS, it provides both an independent input current buffer (IADPT) and a battery current buffer (IBAT) with highly accurate current sense amplifiers. If the platform power exceeds the available power from adapter and battery, a PROCHOT signal is asserted to CPU so that the CPU optimizes its performance to the power available to the system.
The I2C controls input current, charge current and charge voltage registers with high resolution, high accuracy regulation limits. It also sets the PROCHOT timing and threshold profile to meet system requirements.