接口&連接

Renesas?PCIe? Gen3 重計時器系列可為行業提供融合了頂級模擬性能、更低功耗以及大多數系統級功能的信號重計時器,專為計算、存儲和通信領域中要求嚴苛的 2.5Gbps、5Gbps 和 8Gbps 應用而優化設計。

Renesas?的 PCI 重計時器系列的功能包括:

  • 8,16 或 32 通道信號重計時器(4,8 或 16 PCIe 通道)
  • 高級信號調節功能
  • 高級診斷功能
  • 協議特定功能
  • 高級節能功能
  • I2C 編程接口
  • 商業和工業溫度

Download: IDT Signal Integrity Products Overview (PDF)

行業領先的 PCIe 重計時器產品

Renesas?的 PCIe 重計時器(信號調節器)用于提高信號完整性以增強較長的 PCB 走線或電纜的系統性能和可靠性。 PCIe 重計時器消除了輸入信號中的隨機性和確定性抖動,同時避免了符號間干擾,從而可徹底清除輸出抖動預算。 該器件可提供 8、16 或 32 差分,8 GT/s PCI Express 3.0 信道,分別支持 4、8 或 16 個通道。 PCIe 重計時器還可全面支持 PCI Express 5 GT/s 和 2.5 GT/s 功能。

Renesas?的 PCIe 重計時器擁有帶自適應判決反饋均衡器 (DFE) 的完整 CDR 架構,并可通過串行接口訪問多種控制選項。 該器件具有每信道微型控制器,可進行自我配置,從而通過均衡訓練進行自動調節以獲得最佳性能。 微型控制器可管理每條鏈路的功能,包括 128/130b 編碼、降速以兼容 PCIe Gen 1 和 Gen 2、接收器檢測及終端控制。

Renesas?的所有 PCIe 重計時器均采用非線性、自適應的多級均衡器,并帶有模擬前端和 5 抽頭 DFE。 DFE 的反饋濾波器可完全消除前端符號的 ISI 失真,并通過數字量化消除濾波器的輸出噪聲。 濾波器抽頭權值可通過串行配置進行調整。

默認均衡、去加重和 TX 全面擺幅設置均為引腳可編程。 PCIe 重計時器可為作為 SMBus 或 I2C 器件的每個操作功能配置提供廣泛的可配置性。 此外,它們還可提供從串行 EEPROM 下載配置數據的主操作模式。 串行總線還可對大量狀態寄存器進行檢查。

PCIe 重計時器為已校準的輸入端提供 100 歐姆標稱的默認信號終端設置,必要時還可通過編程調整為 85 歐姆標稱。 輸入信號檢測閾值可針對有效有源信號電平進行調整,并支持電空轉。

此外,Renesas 的 PCIe 重計時器可支持 JTAG 和 AC JTAG 以促進生產板測試,并提供內置的圖案發生器以方便進行實驗室和現場試驗。 可提供各種軟件以支持測試和調試,包括用于設置和保存器件配置的 PC 實用程序,以及支持遠程現場診斷的眼睛捕捉工具。

重計時器設備使用 1.0 V、1.8 V 和 3.3 V 電源電壓,可提供多種功能以盡可能降低功耗,其中包括每個鏈路的活動狀態電源管理 (ASPM)。

關于 PCIe 重計時器
因受到發射器、接收器和信道特性影響,高速信號到達終端接收器時會弱化到不可接受的程度。 PCIe 重計時器可補償電纜和 PCB 走線衰減及 ISI 抖動,確保在目標接收器獲得最小的抖動量和最大的眼開度。 上述目標可通過增強所發射的信號、均衡所接收的信號,或在由于信道長度或由導通孔和連接器所產生的不連續性而導致單獨采取其中一項措施不足以實現時同時采取這兩項措施來實現。 Renesas 重計時器是解決刀片服務器、企業存儲、通信系統以及云計算中信號完整性問題的理想選擇。

視頻和培訓

IDT PCIe 3.0 Retimers for High-Speed 8Gbps Signal Conditioning

Description

IDT PCI Express 3.0 retimer for high-speed signal conditioning up to 8Gbps. Delivers signal quality over extended distances while offering simplified design by alleviating board layout constraints. These devices incorporate advanced receive equalization and transmit de-emphasis capabilities, as well as diagnostic features that help IDT customers achieve a simplified design with faster time-to-market. The devices all offer power savings modes for the lowest-possible power consumption. Presented by Ken Curt, Product Manager, Integrated Device Technology, Inc. Learn more at www.idt.com/go/PCIeSIP.

Transcript

Hi, My name's Ken Curt . I'm project manager for IDT's Signal Integrity product line. Today I'd like to talk about our PCI Express 3.0 Retimer products for high speed eight gigabit per second signal conditioning.
 
What I'm showing here is a diagram of a server. Now this diagram shows multiple uses for IDT Signal Conditioning products, including for SAS, SATA, USB 3.0 and other protocols. However, in the middle of this picture, with the bright red border, shows our PCI Express Gen3 Retimer. And in this case, you see it's connected up to IDT's new Enterprise Flash Controller as one example application.
 
Another common application is the use of signal conditioners in blade servers. This diagram shows the signal conditioner on each of two blades within the chassis, and the purpose of the conditioner is to get the signal across this long back plane, which can be up to 20 inches or even 30 inches of trace, when the trace on the blades themselves is considered. So crossing a trace of that long with two connectors in the path is a challenge, especially at eight gigabit per second PCI Express. And that's the purpose for IDT's Retimer Product. In this case, it's shown as the TO816P, which is an eight lane 16-channel Retimer. 
 
This slide shows the block diagram of our Retimer, again, the 16-channel device. You can see, going from top to bottom, the 16 lanes. But at the very top, the interface to the real world, the physical layer interface, begins with the receiver and transmitter equalizers. Below that you'll see the serializer, deserializer, the SerDes. And below that you'll see a micro-controller. Each channel of this device has its own micro-controller for coordinating various initialization and power management functions in real-time, within this device. As we go below the micro-controller, you'll see a routing function. That supports simple routing, such as lane reversal, polarity swapping, and other simple things that are like that. It's not a packet switch, of course. Off to the right side of this image, you'll see the two I2C or SMBus ports. There's a master and slave port, to give complete flexibility in your system application. And below that you'll see the configuration vector, which is important to achieving the very low 10^-12 error rate that PCI Express Gen3 automatically negotiates to. There’s also a JTAG interface, and immediately below that you see the clock. A retimer device, of course, requires a reference clock input.
 
To hit the highlights of our Gen3 Retimer, first of all, it's fully PCI Express Gen3 specification compliant. It's also fully downwards compatible to the 5-gigabit and Gen2 and 2.5-gigabit Gen1 specifications. I showed earlier one version of this device, the 16 channel version. We're actually planning for two versions of the product. There's the 16 channel version, which will come in a 196-pin BGA package. There's also the 100-pin BGA package which is footprint compatible with our four-lane repeater device. So that's a four-lane retimer which is the T0808P version. To go into the rest of the features, the receiver begins with a high-sensitivity, of course, high-speed analog CTLE Equalizer Stage, or continuous linear equalizer, and that's followed by a decision feedback equalizer, a DFE, or a digital equalizer stage. That exceeds PCI Express Gen3 specifications and provides the compensation for channel loss and jitter, and ISI or intersymbol interference that's picked up from vias and other discontinuities, connectors and things like that in the channel.  The transmitter portion of this device includes a four-tap FIR filter. This also exceeds PCI Express Gen3 requirements and its purpose is to support output waveform shaping or pre-compensation of the signal for driving across long traces. Not only can we adjust the transmit amplitude, we can adjust the waveform characteristics, or shape, we can adjust the slew rates, as well as the IO terminations for input and output. So there's tremendous flexibility in the IO capabilities and configuration of this device. A very important function, and unique to PCI Express Gen3, is the automatic negotiation process for Gen3 configuration parameters. So the receiver, equalizer and the transmitter stage all have to be configured. This is handled by a new procedure or protocol within the PCI Express Gen3 standard. In addition to the automatic equalization, our device automatically adapts for different rate changes and optimizes for the actual rate of operation. So for example, if someone plugs in a Gen1 host plus adapter or graphics card, for example, our device will optimize for the 2.5 gigabit per second data rate. Very important at the high eight-gigabit per second performance is automatic calibration. So our retimers automatically calibrate for output skews, they'll calibrate the termination impedances and other functions within this device to make the signals and the timing as close to ideal as possible. Of course, at eight gigabits per second, all these margins become very important. Our device has full support for automatic power-saving states, such as the L0S state that Intel's been promoting heavily, lately. If the root complex and end point device go into a power-down state our device will, of course, follow that to achieve the lowest overall system power that's possible. Our retimers support either independent clocks or a common spread spectrum clock. So you have multiple options in terms of clocking. Our devices also support hot swapping. And finally, the retimers offer built-in instrumentation capabilities. There's a built in pattern generator and checker function, as well as an on-die scope capture capability. And this is very important. If you think back to that blade server application, where you have retimer parts on two blades at each end of the channel, from the transmitter side, you can now generate a pattern with the pattern generator function. That pattern can output a signal and you can adjust the output swing and emphasis characteristics, the slew rate. You've got full control over the output characteristics. Now that signal will then pass down the channel to the receiver. Now if the receiver is our retimer you have the ability to capture the input waveform either at the pin or after equalization. And of course, you can adjust your receiver characteristics, as well, input equalization as well as input sensitivity. So now you have the ability to margin your channel to provide optimum margins for operation. Of course PCI Express Gen3 can do that all automatically. As part of this instrumentation feature, you can output the data to a Windows based PC and look at it under a GUI, a user interface that IDT also provides. So it's software accessible. Being software accessible means it's very convenient to debug within the lab but also once the system is deployed within the field you could conceivably even access the information remotely, via the internet. So a very powerful tool with very powerful capabilities built into this retimer. 
 
To wrap up the advantages that IDT brings in terms of signal conditioning products, we have best in class analog performance, and this is hereditary. It's based on our experience with building high-speed memory buffers, the physical layout interface of those, built on our experience with PCI switching and SRIO switching and other devices. So we have excellent skills in the analog domain. We also consider these devices to be server-class or server-grade signal conditioning devices. And by that we mean that they have a lot of configuration capabilities, including the ability for automatic training under PCI Express Gen3. We wrap around our semi-conductor products a full suite of hardware development tools. I'd already mentioned the GUI that we have available. We have the instrumentation capabilities in these devices to make debug and design easy. And, finally, we have an excellent support team for our Signal Integrity products. The engineers are skilled in the unique requirements around signal conditioning and the unique problems that they present within your system. 
 
So I'd like to conclude on that note, and thank you for your time and attention.