The BQ25773 is a Narrow VDC buck-boost charger controller for portable electronics such as notebook, detachable, ultrabook, tablet, and other mobile devicesoxygen concentrator, ventilator, and portable electronics such as tablet and other mobile devices with rechargeable batteries. It provides seamless transition between different converter operation modes (buck, boost, or buck-boost), fast transient response, and high light load efficiency.

The BQ25773 supports a wide range of power sources, including USB-C PD EPR ports, legacy USB ports, traditional AC-DC adapters, and so forth. It takes input voltage from 3.5 V to 40 V and charges a battery of 2 to 5-cell in series. In the absence of an input source, the BQ25773 supports the USB On-the-Go (OTG) function from a 2- to 5-cell battery to generate an adjustable 3 V to 5 V at the USB port with 20-mV resolution.

When only the battery powers the system and no external load is connected to the USB OTG port, the BQ25773 provides the Vmin Active Protection (VAP) feature. In VAP operation, the BQ25773 first charges up the voltage of the input decoupling capacitors at VBUS to store a certain amount of energy. During the system peak power spike, the huge current drawn from the battery introduces a larger voltage drop across the impedance from the battery to the system. The energy stored in the input capacitors will supplement the system, to prevent the system voltage from dropping below the minimum system voltage and leading the system to a black screen. This VAP is designed to absorb system power peaks during the periods of high demand to improve system turbo performance, which is highly recommended by Intel for the platforms with a 2S battery.

The BQ25773 features Dynamic Power Management (DPM) to limit input power and avoid AC adapter overloading. During battery charging, as system power increases, charging current is reduced to maintain total input current below adapter rating. If system power demand temporarily exceeds adapter rating, the BQ25773 supports the NVDC architecture to allow battery discharge energy to supplement system power.

The BQ25773 monitors adapter current, battery current, and system power. The flexibility of the programmable PROCHOT output goes directly to the CPU for throttling back when needed.

The latest version of the USB-C PD specification includes Fast Role Swap (FRS) to ensure power role swapping occurs in a timely fashion so that the device(s) connected to the dock never experience momentary power loss or glitching. The device integrates FRS with compliance to the USB-C PD specification.

The TI patented switching frequency dithering pattern can significantly reduce EMI noise over the entire conductive EMI frequency range (150 kHz to 30 Mhz). Multiple dithering scale options are available to provide flexibility for different applications to simplify EMI noise filter design.

In order to be compliant with Intel IMVP8 / IMVP9, the BQ25773 includes a PSYS function to monitor the total platform power from the 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 the adapter and battery, a PROCHOT signal is asserted to the CPU so that the CPU optimizes its performance to the power available to the system.

The I²C host 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.