ref: https://vivek-singh.medium.com/system-design-cheat-sheet-318ba2e34723

本篇文章是一個筆記文，紀錄關於 System Design 路上常遇到的架構與元件，譬如
1. LoadBalancer
2. Caches
3. Queues
4. Configuration Service
5. API Gateway
6. Service Mesh
7. CDN
8. Cassandra
9. Snowflake
10. Numbers

每個概念都還會附上一些相關影片與文章，也因為是個筆記內容，因此每個元件的介紹都不會非常詳細，都是小小段落介紹每個元件的最基本概念。
譬如 LoadBalancer 的筆記有
1. L4/L7 兩種的差異
2. AWS 上 ELB/ALB/NLB 的三種差異
3. LB 的演算法， Round Robin,Weighted RR, Least Connection/Response Time/Resource based 等

Caches
1. 實作有 Memcached, Redis 等相關專案
2. 什麼時候會使用 Memcached:
a. 需求簡單，譬如單純 Key/Value 字串，可以輕易地透過調整 cores/threads 來調整效能。
b. Volatile，沒有儲存機制
c. 只有 LRU 的 Cache 演算法
d. Key 最多 250B, Value 最多 1MB
3. 什麼時候使用 Redis
a. 需要儲存 object，而非單純 string
b. 支援多種演算法
c. 支援 data store，可以達到 non-volatile 效果
d. 可以支援 Set/Hash/List/Sorted Set 不同型態

這類型的文章對於踏入 System Design 能夠提供一個簡易的入門介紹，先有哪些類別需要學習，再針對每個類別獨立學習也是一個不錯的學習路徑。

#數位類比轉換器DAC #類比介面 #評估板 #微控制器MCU

【DAC 效能有多精確？一試便知！】

集成非易失性儲存器 (EEPROM) 的類比轉換器 (DAC)，允許在斷電時保存配置數據，以減少微控制器 (MCU) 成本並簡化系統設計；而 1 LSb 的積分非線性 (INL) 高精度控制，可改善整體靜態和動態性能，有時更是特定應用的成敗關鍵。現在，透過易用評估套件，可針對特定應用測試整體系統的功能和效能，並且讓 DAC 每個通道都能靈活、獨立操作內部參考電壓。

演示視頻：
《Digital-to-Analog Converters》
https://www.microchip.com/design-centers/data-converters/digital-to-analog-converter?utm_source=compotechasia.com&utm_medium=LeaderboardAd&utm_content=MSLD_860x80&utm_campaign=HighSpeedSARADC

#微芯科技Microchip #MCP47CMB22 #MCP48FEB21 #MCP4728

P.S.《COMPOTECHAsia 電子與電腦》在 YouTube 也有專屬頻道哦！歡迎各位朋友訂閱＋開啟小鈴鐺。
https://www.youtube.com/user/compotechasia/videos

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