Taking Control of USB Type-C® Power Delivery

By QiKun Wu, Charging and Isolation Marketing Manager

Since the USB Type-C specification was first published in 2014, it has become the go-to connector standard for carrying power, video, audio, and other data.

USB Type-C (also known as USB-C) is increasingly being used to supply power for battery-powered devices and other types of equipment, including routers, wireless speakers, power banks, and power tools. There is a significant trend to transition away from legacy and proprietary ports to a standardized USB-C power port for most battery-powered devices and those using a DC power input.

While the original USB-C specification required cables and connectors to support a minimum of 60W, there has been a growing demand for higher power.

In this blog, we'll look at the power delivery abilities and requirements of USB-C, including the latest high-power variants, and how design engineers can create efficient system designs for them.

We will also consider two USB Power Delivery (PD) sink controllers from Diodes Incorporated (Diodes), the AP33771C and AP33772S, and how they address the needs of USB-C power.

Powering up

The previous version of the standard, known as the USB-C PD3.0 Standard Power Range (SPR), maxed out at 100W. Now, the USB Type-C PD3.1 Standard supports power delivery of up to 240W. This is called extended power range (EPR) and is sufficient to power high-end gaming laptops, large monitors, and other high-power devices.

USB-C PD3.1 includes Adjustable Voltage Supply (AVS). This is a protocol that allows the voltage to be specified in 100mV steps, from 15 to 48V. For example, to provide 140W, a charger might deliver 5A at 28V over USB PD3.1.

This new standard is starting to find uses in laptops, chargers, and power banks that require more than 100W, with multiple vendors offering suitable products.

The Diodes Advantage: Flexible, Simple and Fully Featured

To meet the needs of USB-C, Diodes has launched the AP33771C and AP33772S sink controllers. These provide a simple and versatile USB PD3.1 EPR solution in sink-side devices that use USB Type-C as a power source.

Both controllers have built-in application firmware that automatically carries out the PD3.1 negotiation procedure with the attached USB PD3.1-compliant charger to obtain the required power levels.

The AP33771C provides a simplified solution with six pre-set output voltages and eight pre-set output currents, which are both set by external resistors. Where more flexibility is needed, the AP33772S uses its I2C interface and GPIO pins to communicate with a host microcontroller (MCU). This enables it to determine a more flexible power profile and other intelligent power-related management functions.

For USB-C power systems, the two controllers provide a versatile solution that supports AVS of up to 28V. They enable product designers, particularly when transitioning from proprietary and legacy charging ports, to develop smaller applications with fewer components that can charge more quickly.

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Posted in Technology; Tagged Analog Products, Sink Controllers, USB, USB PD, USB Type-C; Posted 3 days ago by By QiKun Wu | Charging and Isolation Marketing Manager