https://hwwiki.net/ 2026-06-18T02:55:08+00:00 https://hwwiki.net/ https://hwwiki.net/lib/tpl/dokuwiki/images/favicon.ico text/html 2026-06-15T06:57:53+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E5%85%83%E5%99%A8%E4%BB%B6:ic:memory:ddr:start&rev=1781477873&do=diff DDR(Double Date Rate) 标准组织为JEDEC，官网jedec.org，早期的标准文档个人注册后可免费下载，近期发布的需要付费 常用标准 DDR: * DDR5: JESD79-5.pdf * DDR4: JESD79-4C.pdf * DDR3U: JESD79-3-2.pdf * DDR3L: JESD79-3-1A-01.pdf * DDR3: JESD79-3F.pdf * DDR2: JESD79-2F.pdf * DDR1: JESD79F.pdf LPDDR: * LPDDR5/5X: text/html 2026-06-08T08:26:06+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Addr5-more-than-a-generational-update-wp.pdf&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1780878366&tab_details=history&mediado=diff&do=media text/html 2026-06-07T15:59:09+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E8%AE%BE%E8%AE%A1:%E5%8E%9F%E7%90%86%E5%9B%BE:cadence_design_entry:start&rev=1780819149&do=diff Cadence Design Entry 常用功能 原理图库添加 在项目Setup设置中的cds.lib文件中，添加对应的库路径。 批量替换元器件 检查单网络 * 选择Tools →Packager Utilities →Electrical Rules Check * 在对话框中找到Single Node Nets 检查项 text/html 2026-06-07T15:55:21+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E8%AE%BE%E8%AE%A1%3A%E5%8E%9F%E7%90%86%E5%9B%BE%3Acadence_design_entry%3Ahdl%E6%89%B9%E9%87%8F%E6%9B%BF%E6%8D%A2%E5%85%83%E5%99%A8%E4%BB%B6.png&ns=%E8%AE%BE%E8%AE%A1%3A%E5%8E%9F%E7%90%86%E5%9B%BE%3Acadence_design_entry&rev=1780818921&tab_details=history&mediado=diff&do=media <img src="https://hwwiki.net/lib/exe/fetch.php?w=500&h=418&t=1780818921&amp;tok=cfcb0e&amp;media=%E8%AE%BE%E8%AE%A1:%E5%8E%9F%E7%90%86%E5%9B%BE:cadence_design_entry:hdl%E6%89%B9%E9%87%8F%E6%9B%BF%E6%8D%A2%E5%85%83%E5%99%A8%E4%BB%B6.png" alt="设计:原理图:cadence_design_entry:hdl批量替换元器件.png" /> text/html 2026-06-07T15:47:53+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E8%AE%BE%E8%AE%A1:%E5%8E%9F%E7%90%86%E5%9B%BE:orcad:start&rev=1780818473&do=diff OrCAD 常见问题 无法插入图片 原理图内插入图片时，如果像素过大，则无法插入，软件也无任何提示，可用Windows自带的画图工具，减小像素大小后插入。 操作见：如何将图片像素变小？ 图片相对位置改变 带有图片的原理图封装，在旋转、镜像的过程中，图片中各部分的相对位置可能会改变。 text/html 2026-06-07T15:36:14+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E8%AE%BE%E8%AE%A1:%E5%8E%9F%E7%90%86%E5%9B%BE:%E5%8E%9F%E7%90%86%E5%9B%BEchecklist&rev=1780817774&do=diff 原理图Checklist 通用 * 原理图的结构、字体、元件、注释等规范（不涉及具体电路设计）请参考原理图设计规范-OrCAD Capture CIS * 使用软件工具，检查是否有单网络，并确认各器件的NC脚是否可NC * 检查是否有错误的网络连接，如器件两端的网络相同。 text/html 2026-06-07T11:56:36+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E8%AE%BE%E8%AE%A1:pcb:pcb_checklist&rev=1780804596&do=diff PCB Checklist 布局 封装 * 确认哪些元器件无PCB封装，提供资料（规格书、2D或3D结构图等）给EDA工程师新建封装。对于老封装，则需要提供对应的封装库给EDA工程师，并注意下有无用错库。 text/html 2026-06-07T11:31:01+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E6%A0%87%E5%87%86:wifi:start&rev=1780803061&do=diff Wi-Fi Wi-Fi的标准由IEEE组织制定，网站：IEEE SA，文档无法免费下载，但有部分常用的可以免费下载，参见链接IEEE GET Program。 常用标准 在线阅读和下载链接如下： 11a/b/g/n/ac（Wi-Fi 5及以下）：IEEE Std 802.11™‐2020 11ax（Wi-Fi 6）： text/html 2026-06-01T08:55:02+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E8%AE%BE%E8%AE%A1:pcb:start&rev=1780275302&do=diff PCB PCB叠层图如下PCB设计大全：使用OrCAD+Capture与PCB+Editor: CHAPTER 1 ： 板材 标准详见IPC-4101C Specification for Base Materials for Rigid and multilayer Printed Boards 常用PCB板材见博锐电路：PCB板材汇总表 由PCB叠层图可知，PCB由覆铜板（芯板Core）和半固化片（Prepreg，简称PP）压合而成。 覆铜板的制作如下图，其材料为树脂、增强材料以及导电铜箔$$ C_{\text{via}} \, [\mathrm{pF}] = \frac{1.41 \cdot \varepsilon_r \cdot T \cdot D_{\text{pad}}}{D_{\text{antipad}} - D_{\text{pad}}} $$$$ \begin{array}{|c|c|c|} \hline \textbf{符号} & \textbf{物理意义} & \textbf{单位} \\ \hline C_{\text{via}} & \te… text/html 2026-05-14T16:55:10+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E6%A0%87%E5%87%86:3gpp:5g_nr:start&rev=1778748910&do=diff 5G NR FR1 Band Vs Channel Vs Freqency 下表给出了5G NR FR1各频段的信道和频率。 5G NR FR1 operating band Uplink operation band Downlink operation band Duplex Mode Tx-Rx Freq Separation ΔFRaster (kHz) Uplink text/html 2026-05-05T10:21:23+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?id=%E6%A0%87%E5%87%86:3gpp:4g_lte:start&rev=1777947683&do=diff 4G LTE Band Vs Channel Vs Frequency 下表给出了4G LTE各频段的信道和频率。 4G LTE E-UTRA Operating Band Uplink operation band Downlink operation band Duplex Mode Tx-Rx Freq Separation Channel Number 1.4 MHz text/html 2026-02-01T20:11:57+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Afigure_2_simplified_block_diagram_of_2n-prefetch_read.png&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1769947917&tab_details=history&mediado=diff&do=media <img src="https://hwwiki.net/lib/exe/fetch.php?w=500&h=223&t=1769947917&amp;tok=d0535f&amp;media=%E5%85%83%E5%99%A8%E4%BB%B6:ic:memory:ddr:figure_2_simplified_block_diagram_of_2n-prefetch_read.png" alt="元器件:ic:memory:ddr:figure_2_simplified_block_diagram_of_2n-prefetch_read.png" /> text/html 2026-02-01T20:10:18+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Afigure_3_simplified_block_diagram_of_2n-prefetch_write.png&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1769947818&tab_details=history&mediado=diff&do=media <img src="https://hwwiki.net/lib/exe/fetch.php?w=500&h=326&t=1769947818&amp;tok=9d27a5&amp;media=%E5%85%83%E5%99%A8%E4%BB%B6:ic:memory:ddr:figure_3_simplified_block_diagram_of_2n-prefetch_write.png" alt="元器件:ic:memory:ddr:figure_3_simplified_block_diagram_of_2n-prefetch_write.png" /> text/html 2026-02-01T20:04:45+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Atn-46-05_general_ddr_sdram_functionality.pdf&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1769947485&tab_details=history&mediado=diff&do=media text/html 2026-02-01T19:57:44+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Afigure_4_ddr4_solution_to_prefetch_of_eight.png&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1769947064&tab_details=history&mediado=diff&do=media <img src="https://hwwiki.net/lib/exe/fetch.php?w=500&h=288&t=1769947064&amp;tok=9a983a&amp;media=%E5%85%83%E5%99%A8%E4%BB%B6:ic:memory:ddr:figure_4_ddr4_solution_to_prefetch_of_eight.png" alt="元器件:ic:memory:ddr:figure_4_ddr4_solution_to_prefetch_of_eight.png" /> text/html 2026-02-01T19:56:47+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Afigure_3_historical_dram_prefetch.png&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1769947007&tab_details=history&mediado=diff&do=media <img src="https://hwwiki.net/lib/exe/fetch.php?w=500&h=302&t=1769947007&amp;tok=f8ae26&amp;media=%E5%85%83%E5%99%A8%E4%BB%B6:ic:memory:ddr:figure_3_historical_dram_prefetch.png" alt="元器件:ic:memory:ddr:figure_3_historical_dram_prefetch.png" /> text/html 2026-02-01T19:54:38+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Afigure_2_sdram_performance_scaling_enabled_by_prefetch.png&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1769946878&tab_details=history&mediado=diff&do=media <img src="https://hwwiki.net/lib/exe/fetch.php?w=389&h=289&t=1769946878&amp;tok=77e04d&amp;media=%E5%85%83%E5%99%A8%E4%BB%B6:ic:memory:ddr:figure_2_sdram_performance_scaling_enabled_by_prefetch.png" alt="元器件:ic:memory:ddr:figure_2_sdram_performance_scaling_enabled_by_prefetch.png" /> text/html 2026-01-16T08:35:59+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Addr_revision_20260116a.xlsx&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1768523759&tab_details=history&mediado=diff&do=media text/html 2026-01-13T14:20:09+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E8%AE%BE%E8%AE%A1%3Apcb%3Aallegro%3Ano_zoom_to_object.png&ns=%E8%AE%BE%E8%AE%A1%3Apcb%3Aallegro&rev=1768285209&tab_details=history&mediado=diff&do=media <img src="https://hwwiki.net/lib/exe/fetch.php?w=484&h=500&t=1768285209&amp;tok=1d0273&amp;media=%E8%AE%BE%E8%AE%A1:pcb:allegro:no_zoom_to_object.png" alt="设计:pcb:allegro:no_zoom_to_object.png" /> text/html 2026-01-09T09:08:02+00:00 hwwiki (wzj07220624@undisclosed.example.com) https://hwwiki.net/doku.php?image=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr%3Alpddr3_jesd209-3.pdf&ns=%E5%85%83%E5%99%A8%E4%BB%B6%3Aic%3Amemory%3Addr&rev=1767920882&tab_details=history&mediado=diff&do=media