Introduction

OCuLink, short for "Optical-Copper Link," is a peripheral connection standard that allows you to connect PCIe devices using an external cable rather than an internal slot The interface was developed by the PCI-SIG, the Body for standardization and norming of the PCI interface (Peripheral Component Interconnect Special Interest Group). It is designed to provide a smaller, more flexible, and more efficient PCIe expansion solution.

Express, OCuLink is a pure PCIe channel and does not include a DP channel. Its transmission loss is relatively low when connecting an external graphics card dock. OCuLink of PCIe 3.0×4 can reach a bandwidth of 32Gbps, while PCIe 4.0×4 can reach a bandwidth of 64Gbps, which is more advantageous than the maximum bandwidth of 22Gbps of Thunderbolt 3 and the maximum bandwidth of 32Gbps of Thunderbolt 4. 

The loss of external graphics card docks is relatively small, so more and more laptops and mini PCs are beginning to adopt the OCuLink interface.

Parade Technologies OCuLink Interface

Parade Technologies is a manufacturer founded in 2005 that focuses on the research and development of various high-speed transmission chips, image display chips, and touch control chips. Its chips support HDMI, DisplayPort, USB, PCI Express, etc., and are used in network and storage devices, personal computers, automotive equipment, consumer electronics, and display panels.

ChargerLAB got a demo of the OCuLink interface from Parade Technologies, let’s take a look!

This is the front of the PCB of the OCuLink interface.

PS8570 is a unidirectional, 4-channel linear redriver that supports PCIe® (PCI Express®) Gen 4, with data rates up to 16.0GT/s. The 2×2 crossbar switch supports muxing, de-muxing or cross operation. It is ideal for applications incorporating high lane count PCIe bus widths such as workstations and enterprise data center systems including storage and servers. 

This PS8570 is used for the upstream PCIe channels.

PS8570 comes with very low power which contributes towards lower overall system power and less heat dissipation for the mobile applications.PS8570 removes unwanted and potentially error-inducing signal distortion that occurs in the physical transmission interface including PCIe interconnect cables, PCB traces, and connectors.  PS8570 enhances data transmission reliability and enables longer PCIe interconnect cables and/or PCB traces, enabling system scalability.  In a typical application the PS8570 is used in pairs, with one PS8570 used for the downstream PCIe channels, and another PS8570 used for the upstream PCIe channels.

The PS8570 adopts a 2.8mm x 6mm 38-pin QFN package, making it ideal for applications that utilize high lane count PCIe bus widths, such as workstations and enterprise data center systems, including storage and servers.

This is the back of the PCB. This PS8570 is used for the downstream PCIe channels.

The OCuLink interface is similar to the DP interface, but although the two are similar in shape, the OCuLink interface is slightly smaller than the DP interface and the number of pins is also different.

The length of the demo is about 29.22 mm (1.15 inches).

The width is about 15.78 mm (0.62 inches).

The thickness is about 1.33 mm (0.052 inches).

Since the demo is too light, we weighed it with the base. The base weighs about 16.8 g (0.59 oz), so the actual weight of this demo is about 1.4 g (0.049 oz).

Summary of ChargerLAB

OCuLink is a connection system for the PCI Express area. The interface has a Small-Form-factor which is optimized for internal and external enclosure usage. OCuLink cables are a cost-effective possibility for an external PCIe extension. Compared with Thunderbolt, it can significantly reduce transmission loss and improve the performance of external devices because it uses native PCIe transmission.

As a leading manufacturer in the field of data transmission interfaces, Parade Technologies launched the PS8570, which supports PCIe Gen 4 high-speed data transmission with a transmission rate of up to 16GT/s, providing reliable and efficient solutions for various applications. With the support of more and more laptops and mini PCs, and the development of OCuLink technology, we believe that the OCuLink interface will gradually come to the fore and enter the public eye.

Related Articles：
1.  OCuLink | Review of Lenovo ThinkBook14+ 2024 with Lenovo TGX GPU Dock
2. Review of AOOSTAR AG01 OCuLink GPU Dock
3. OCuLink | Review of Minisforum DEG1 eGPU Dock