Diodes Incorporated — Analog and discrete power solutions

訊號完整性 - ReDriver/ 訊號中繼器 / 調節器

Redriver,也稱為訊號中繼器(Repeater IC),可以重新產生訊號,在高速介面上增加訊號品質。高速的訊號頻率造成設計上可用的寬裕度降低,增加設計耐用、高性能系統的難度。透過使用同等化(equalization)、預強調(pre-emphasis)和其他技術,可讓單一ReDriver調整與矯正傳輸端上頻道的損失,並在接收端上恢復訊號完整性。因此可以在接生端產生寬裕度足以滿足傳送可靠訊號、減少訊號錯誤率的眼圖 。

redrivers application2

Redriver訊號中繼器(Repeater IC)是解決設計複雜設計難題的關鍵的技術,現今各種應用的高速連結所需的高速資料傳輸通訊協議都可以應用。為了讓更佳完善訊息能夠在電路上傳送,採用極佳的訊號調適技術,提供redrivers。Redrivers提供比基於協議訊號更好的性能,不需要在終端點終止信號,然後重新傳送,因此消除延遲和附加系統成本。此外,redrivers調節與傳遞訊號是透過物理層工作,因此有極少的訊號抖動 。

Signal Integrity - ReDrivers/Repeaters/Signal Conditioners Details

 

Diodes ReDrivers address the five major issues negatively impacting the signal integrity of high-speed interfaces:

Signal Attenuation: High-speed signals, including differential signals, introduce noise and jitter that causes signal voltage swings to overshoot or undershoot the optimal eye opening.  This results in a degraded signal during high-speed signal switching.  

Signal Strength: Interfaces are increasingly being integrated into CPU chipsets.  While providing excellent performance in the lab, many of these chipsets are often not strong enough to provide reasonable design margin to meet compliance specs when designed into real-world systems with multi-layer boards, long traces, and extended cable lengths.

 

Signal Distance: Layout constraints, controller-to-connector separation, multiple PCB layers, vias, daughterboard connectors, and extensive cable lengths all contribute to signal distance and greater signal degradation.  For example, signal losses over FR4 PCB traces are typically 0.3dB per inch at 2.5 Gbps and 0.9 dB at 8 Gbps.

 

Noise: Both random and deterministic noise degrade signal integrity from a variety of sources, including crosstalk from other signals.  Another common source of random jitter is a noisy clock source that does not have good isolation or has impedance mismatches.

Lack of end-to-end control: When an interface connects to an external subsystem or device, designers do have not control over the signal distance, board vias, connectors, and cables over which the signal must still pass to reach its destination.  This can increase noise, jitter, attenuation, and insertion losses, and cause otherwise well-designed devices to fail to interface to equipment from other manufacturers.

The challenge for OEMs is that, as signal speeds increase, these factors become more pronounced, causing reliability, throughput, and quality to suffer.  To help developers maintain signal integrity, Diodes offers unparalleled signal conditioning technology with a comprehensive portfolio of devices for PCI Express, USB, Thunderbolt, SAS/SATA, Bluetooth, Wi-Fi, HDMI, and other popular standards.  Benefits include:

Superior Signal Quality: Diodes  ReDrivers have the lowest jitter and attenuation for the highest performance in the industry.  Comparative studies are available under NDA.

Lowest Crosstalk: By minimizing crosstalk, Diodes keeps channel-to-channel and part-to-part skew low.

Highly configurable: To provide developers greater flexibility, Diodes' ReDrivers can be configured on a per channel basis via an MCU over I2C rather than having to be pinstrapped or hardwired like other technologies.

Power Efficiency: These devices are architected for both low power operation and efficient power consumption.  For example, Diodes' SAS/SATA redrivers consume less than 100 mW per channel and have the best power efficiency on the market.

Multi-port: Diodes' redrivers support a variety of multi-channels configurations, providing flexibility while enabling greater integration and cost savings.  

Multi-protocol: Diodes' is the only manufacturer in the industry to offer a comprehensive portfolio of redrivers that work in both SATA and SAS environments.

Flexible packaging: Diodes' redrivers come in a variety of packaging options to meet the specific cost, performance, and power needs of your application.  With devices on the order of 4 mm x 4 mm, these redrivers can be placed close the interface connector to minimize signal losses.

Improving signal integrity increases the overall signal margin of systems.  OEMs can use this increased signal margin to:

  • Improve signal reliability and robustness
  • Increase the maximum trace distance and/or cable lengths over which signals can reliably be run
  • Reduce the number of board layers required to isolate signals effectively and substantially lower system cost
  • Ensure connectivity regardless of the quality of the external device to which a system is connected
  • Increase flexibility to simplify design, speed time-to-market, and reduce system cost by being able to use lower precision components elsewhere in the signal chain.

Diodes' is the market leader in redriver technology across applications, including networking, embedded computing, and communications, among others.  For example, in the server market, Diodes' was the first redriver manufacturer to achieve SATA3 compliance, and its technology has been adopted in more than 80% of server storage designs.  Diodes' redrivers are also part of many controller vendor reference designs, including Intel.  

As part of its commitment as the signal integrity leader, Diodes' offers unparalleled design support to its customers, including availability of evaluation boards, professional schematic and layout review, and system simulation to optimize the key opening using S-Parameter models, AMI-IBIS, or HSPICE.

High speed SAS 2.0, SATA 3.0, PCIe 2.0,PCIe 3.0, USB 3.0, DP 1.1 and DP 1.2

  • Increased signaling distance
  • Increased design flexibility
  • Standards compliance
  • Improved performance
  • Increased reliability
  • Reduced PCB & cable cost
  • Unique, differentiatted products to maximize the protocol's potential