A new repeater IC is designed to maintain signal integrity for server, storage, and networking applications.
PI3EQX16904GL is a four channel differential linear ReDriver. It also supports PCIe. PCIe stands for Peripheral Component Interconnect and PCIe 4.0 is the latest version of the standard.
According to the company’s announcement of the ReDriver, “The device provides programmable linear equalization, output shift and flat gain to optimize performance on a variety of physical media by reducing inter-symbol interference.”
Block diagram for the PI3EQX16904GL. Image by Diodes Incorporated
Diodes Inc. claims that the PI3EQX16904G is the first ReDriver to be compliant with the PCI-SIG PCIe 4.0 specification and also compliant with the previous PCIe 3.0 / 2.0 / 1.0 standards. It also supports SAS3 / IB FDR / PCIe4 / FC16 and XAUI protocols.
Target applications for devices include:
- Storage servers and AI
- Work stations
- 5G networks
- CPU to network (PCIe NIC card)
- Non-volatile memory interconnects from CPU to storage (NVME)
- CPU-to-CPU interconnects within high-performance compute clusters
A list and descriptions of Diodes Incorporated ReDrivers and related devices can be found here.
What is a ReDriver?
Data rates are increasing on electronic devices of all kinds. In some cases, that data must travel longer physical distances, often across a sea of EMI / RFI, from source to destination. This can cause degradation of signal integrity.
ReDrivers (or re-drivers) are another term for repeater ICs. They serve to “re-lead” the signal, amplify it, and eliminate distortion, resulting in a clean and functional data stream.
The PI3EQX16904GL employs techniques such as equalization and pre-emphasis to adjust and correct for factors at the transmitter end (known channel losses) and also to restore signal integrity at the receiver end. This improves the reliability of communications and enables low bit error rates (BER).
Four-lane data traffic
A “rail” in this context is composed of four cables that form a differential channel. One pair of wires (or PCB signal traces) carries data in one direction and a second pair of wires carries data in the reverse direction, creating a differential channel.
Each of the eight independent 100 ohm lanes supported and augmented by the PI3EQX16904GL supports data rates ranging from 2.5 Gbps to 16 Gbps.
The device requires a supply voltage of 3.3 V ± 0.3 V and operates in a temperature range of -40 ° C to + 85 ° C.
Unit is lead free, halogen and antimony free. It is also RoHS compliant.
The ReDriver PI3EQX16904GL is available in a 42mm x 3.5mm and 9mm TQFN package.
The PI3EQX16904GL. Image by Diodes Incorporated
Diodes Inc. appears to be the first company to offer a device like the PI3EQX16904GL. But, given the widespread adaptation of the PCIe standard, it is doubtful that the distinction will last long. However, here are a couple of notable related devices:
- Asmedia Technology offers the ASM1464… ASM1467 series of ReDrivers at a speed of 5 ohms and 100 ohms. They serve in applications based on USB and SATA in addition to PCIe.
- Texas Instruments offers the S125BR820, a low power repeater / ReDriver designed to support eight channels. These channels carry a high speed interface of up to 12.5 Gbps, such as 40G-CR4, 40G-KR4, SAS / SATA, as well as PCIe.
Have you worked with PCIe before? What is your familiarity with IC repeaters and their applications? Share your thoughts in the comments below.