Introduction

USB4 is the next-generation technical specification for the USB architecture, based on Intel's Thunderbolt 3 protocol and consistent with Thunderbolt 4. The USB4 architecture allows dynamic sharing of a high-speed link with multiple hardwares to provide the fastest data transfer. We previously wrote a USB4 cables buying guide, which you can check out here. And we will share more content related to USB4, including chips and products in the future. Stay tuned for more!

First, let's briefly introduce the HUB controller, which is a chip used for expanding USB ports. It integrates functions like transceivers, MCUs, voltage regulators, and charging circuits. It can expand a single USB port into multiple ports, including video transmission ports and Ethernet ports, which is particularly beneficial for devices with limited ports. Moreover, due to the connection of multiple ports, there is a high demand for speed in this function. As people's requirements for speed and data transfer continue to rise, the previous HUB controllers have become outdated. USB4, with its 40Gbps transfer speed, and the recently launched USB4 2.0 standard with a transfer speed of up to 80Gbps, has undoubtedly gained popularity in the market.

ChargerLAB is here to introduce VIA Labs' VL830 and Realtek's RTS5490 HUB controllers.

About USB4

The USB data transfer protocol was introduced much earlier than USB PD. In fact, USB 1.0 was introduced in 1996, which was the third year of the USB-IF's establishment. The first generation of the USB standard had a transfer rate of only 1.5 Mbps.

ChargerLAB Reveals Two USB4 HUB Controllers from two Manufacturers-Chargerlab

In September 2019, USB4 was officially released with a maximum transfer rate of 40 Gbps, the same as Thunderbolt 3. USB4 has two specifications: USB4 40 with 40 Gbps and USB4 20 with 20 Gbps.

In September 2022, the USB4 2.0 standard was exposed, raising the maximum speed to 80 Gbps. It also adopted a new data architecture, updating the USB PD fast charging standard and the USB-C port and cable standard simultaneously.

USB has come a long way from its initial 1.5 Mbps to the high-speed USB4 2.0, reaching up to 80 Gbps. This transformation is primarily due to an increase in the number of data transmission channels. Specifically, the 2013 upgrade increased the number of differential channels to four pairs and introduced the more capable USB-C port.

While the latest iPhone 15 Pro series is only equipped with a port equivalent to USB 3.2 Gen 1 from 2017, this is still one of the most significant advancements in the iPhone's charging port. It is expected that Apple will build on this foundation to deliver higher-performance USB-C ports in the future.

USB4 HUB Controller

VIA Labs

VL830

VIA VL830 is the first USB4 control solution. It fully complies with the USB4 specification, with a 40Gbps transfer speed, and is compatible with Thunderbolt 4 and Thunderbolt 3. It can transfer a Thunderbolt 4 or USB4 port into four 10Gbps USB 3.2 ports, one USB 2.0 port, and one DP 1.4 port, providing a hub and video conversion in one.

It features one upstream USB4 or Thunderbolt 4 port, five downstream ports, and one DP port with support for 32.4Gbit/s bandwidth, offering a maximum of 8K/60Hz HDR video output. Its hardware also supports digital signature firmware, PWM-driven LED indicators, and firmware upgrades via the USB port or I2C bus. Additionally, the USB port supports charging protocols like BC1.2 and Apple 2.4A.

This is the reference design for VL830. It has a USB-C port that supports Thunderbolt 4 and USB4 input, and it has four USB 3.2, one USB 2.0, and one DP 1.4 output ports.

This is the reference design for docking stations that VL830 supports. It includes a power input, HDMI, DP ports, and two USB 3.2 ports, supporting collaboration with VL10X series controllers for laptop charging.

Here is its block diagram, showing the built-in USB 3.2 hub, supporting four USB 3.2 and one USB 2.0 port, and also a DP 1.4a port, which can be converted to HDMI port using other chips.

VL830 adopts 10 x 10 x 1.03mm FCCSP package, with three supply voltages: 3.3V, 1.05V, and 0.9V.

Realtek

RTS5490

According to TechPowerUp, Realtek recently showcased what may be their first HUB controller, the RTS5490, at the Computex 2023.

It supports transfer speeds of up to 40 Gbps, featuring one upstream port and four downstream ports, compatible with Thunderbolt 3 and USB 3.2 Gen 2x2 (20 Gbps), and supports the latest USB PD 3.1 standard. Additionally, it natively supports DisplayPort 2.1 video transmission.

Currently, Realtek has not announced when docking stations using this solution will be released.

Summary of ChargerLAB

VIA Labs' VL830 chip leads in USB4 control solutions, with a speed of 40Gbps, compatibility with Thunderbolt 4 and Thunderbolt 3. It supports multiple ports, including USB 3.2 and DP 1.4 output, with a maximum of 8K video output. It also has various security features.

Realtek's RTS5490 also supports 40 Gbps, is compatible with Thunderbolt 3 and USB 3.2 Gen 2x2 (20 Gbps), and supports the latest USB PD 3.1 standard. Moreover, it natively supports DP 2.1 video transmission.

ChargerLAB Reveals Two USB4 HUB Controllers from two Manufacturers