Buck converter adds adaptive power sharing

Silanna Semiconductor has claimed the first buck converter power IC to feature intelligent adaptive power sharing. The SZPL3002A buck converter with a built-in USB PD/FC port controller will significantly reduce component count to implement 65-W fast charger and adapter applications with up to four ports, said the company.

The SZPL3002A combines a high-efficiency synchronous buck converter and an advanced port controller in a QFN package measuring  5 × 5 mm. It is built on the company’s wide-voltage, high-frequency point-of-load DC/DC converter technology with higher than 98% efficiency.

Click for a larger image. (Source: Silanna Semiconductor)

The integrated port controller supports USB PD V3.0 Type C interfaces and QC2.0/3.0/4.0/5.0 support for Type A/C connections. The controller’s job is to ensure that the port power adapts to the device’s requirements, delivering power sharing and port power re-balancing functionality across two, three or four ports.

The power IC is the first to use an integrated USB-PD controller, microcontroller, and VCONN cable communications protocol in a DC/DC buck converter, according to the company.

Thanks to the five selectable pre-loaded power contract configurations, designs can use a single ZPL3002A across multiple product designs. “Power re-balancing allocates under-used power on previously connected ports, while protective power throttling automatically reduces current when temperature thresholds are reached,” said Silanna.

Hubie Noto, director of product marketing, Silanna Semiconductor explained: “The SZPL3002A offers one fully programmable contract set plus four pre-programmed sets that are chosen with an external resistor value,” said “Traditional charger PD ports offer a selection of fixed contracts to a device based on available power. These are programmed into the port controller and are based on various voltage and current levels a device might use when connecting. Each port has different power contracts for different power.”

The buck converter offers a selectable switching frequency from 667 kHz to 2 MHz and a 7-V to 27-V input range. The device provides a 3.3-V to 21-V output at 3.25 A (which covers PD + PPS). The RDS(on) of the upper FET is 41 mΩ and 38 mΩ for the lower FET. Other features include a selectable power save mode, selectable soft start time, and protection features such as overcurrent protection (OCP), overvoltage protection (OVP), and overtemperature protection (OTP). It comes with a I2C communication interface.

Key accounts are sampling the SZPL3002A buck converter. It will be released to the general industry in the second half of 2022.