這是我在做大學教授期間推薦給我學生的一本書，非常好，適合入門學習。《python深度學習》由Keras之父、現任Google人工智能研究員的弗朗索瓦?肖萊（Franc?ois Chollet）執筆，詳盡介紹了用Python和Keras進行深度學習的探索實踐，包括計算機視覺、自然語言處理、產生式模型等應用。書中包含30多個代碼示例，步驟講解詳細透徹。作者在github公布了代碼，代碼幾乎囊括了本書所有知識點。在學習完本書后，讀者將具備搭建自己的深度學習環境、建立圖像識別模型、生成圖像和文字等能力。但是有一個小小的遺憾：代碼的解釋和注釋是全英文的，即使英文水平較好的朋友看起來也很吃力。本人認為，這本書和代碼是初學者入門深度學習及Keras最好的工具。作者在github公布了代碼，本人參照書本，對全部代碼做了中文解釋和注釋，并下載了代碼所需要的一些數據集（尤其是“貓狗大戰”數據集），并對其中一些圖像進行了本地化，代碼全部測試通過。（請按照文件順序運行，代碼前后有部分關聯）。以下代碼包含了全書約80%左右的知識點，代碼目錄：2.1: A first look at a neural network（ 初識神經網絡）3.5: Classifying movie reviews（電影評論分類：二分類問題）3.6: Classifying newswires（新聞分類：多分類問題 ）3.7: Predicting house prices（預測房價：回歸問題）4.4: Underfitting and overfitting（ 過擬合與欠擬合）5.1: Introduction to convnets（卷積神經網絡簡介）5.2: Using convnets with small datasets（在小型數據集上從頭開始訓練一個卷積網絡）5.3: Using a pre-trained convnet（使用預訓練的卷積神經網絡）5.4: Visualizing what convnets learn（卷積神經網絡的可視化）
上傳時間： 2022-01-30
上傳用戶：
STM32L053C8T6數據手冊Features ? Ultra-low-power platform – 1.65 V to 3.6 V power supply – -40 to 125 °C temperature range – 0.27 μA Standby mode (2 wakeup pins) – 0.4 μA Stop mode (16 wakeup lines) – 0.8 μA Stop mode + RTC + 8 KB RAM retention – 139 μA/MHz Run mode at 32 MHz – 3.5 μs wakeup time (from RAM) – 5 μs wakeup time (from Flash) ? Core: ARM? 32-bit Cortex?-M0+ with MPU – From 32 kHz up to 32 MHz max. – 0.95 DMIPS/MHz ? Reset and supply management – Ultra-safe, low-power BOR (brownout reset) with 5 selectable thresholds – Ultralow power POR/PDR – Programmable voltage detector (PVD) ? Clock sources – 1 to 25 MHz crystal oscillator – 32 kHz oscillator for RTC with calibration – High speed internal 16 MHz factory-trimmed RC (+/- 1%) – Internal low-power 37 kHz RC – Internal multispeed low-power 65 kHz to 4.2 MHz RC – PLL for CPU clock ? Pre-programmed bootloader – USART, SPI supported ? Development support – Serial wire debug supported ? Up to 51 fast I/Os (45 I/Os 5V tolerant) ? Memories – Up to 64 KB Flash with ECC – 8KB RAM – 2 KB of data EEPROM with ECC – 20-byte backup register
標簽： stm32l053c8t6
上傳時間： 2022-02-06
上傳用戶：
The PW5300 is a current mode boost DC-DC converter. Its PWM circuitry with built-in 0.2? powerMOSFET make this regulator highly power efficient. The internal compensation network alsominimizes as much as 6 external component counts. The non-inverting input of error amplifierconnects to a 0.6V precision reference voltage and internal soft-start function can reduce the inrushcurrent. The PW5300 is available in the SOT23-6L package and provides space-saving PCB for theapplication fields
標簽： pw5300
上傳時間： 2022-02-11
上傳用戶：jiabin
PW4203 is a 4.5-22V input, 2A multi-cell synchronous Buck Li-Ion battery charger, suitable forportable application. Select pin is convenient for multi-cell charging. 800 kHz synchronous buckregulator integrates of 22V rating FETs with ultra low on- resistance to achieve high efficiency andsimple circuit design.The PW4203 is available in an 8-pin SOP package, provides a very compact system solution andgood thermal conductance
標簽： pw4203
上傳時間： 2022-02-11
上傳用戶：
The PW2601 is a charger front-end integrated circuit designed to provide protection to Li-ionbatteries from failures of charging circuitry. The device monitors the input voltage, battery voltageand the charging current to make sure all three parameters are operated in normal range. Thedevice will switch off internal MOSFET to disconnect IN to OUT to protect load when any of inputvoltage, output current exceeds the threshold. The Over temperature protection (OTP) functionmonitors chip temperature to protect the device. The PW2601 also can protect the system’sbattery from being over charged by monitors the battery voltage continuously. The deviceoperates like a linear regulator, maintaining a 5.1V output with input voltages up to the input overvoltage threshold.The PW2601 is available in DFN-2x2-8L package. Standard products are Pb-free and Halogenfree
標簽： pw2601
上傳時間： 2022-02-11
上傳用戶：
The PW2053 is a high-efficiency monolithic synchronous buck regulator using a constantfrequency, current mode architecture. The device is available in an adjustable version. Supply currentwith no load is 40uA and drops to <1uA in shutdown. The 2.5V to 5.5V input voltage range makesthe PW2053 ideally suited for single Li-Ion battery powered applications. 100% duty cycle provideslow dropout operation, extending battery life in portable systems. PWM/PFM mode operationprovides very low output ripple voltage for noise sensitive applications. Switching frequency isinternally set at 1.2MHz, allowing the use of small surface mount inductors and capacitors. Lowoutput voltages are easily supported with the 0.6V feedback reference voltage
標簽： pw2053
上傳時間： 2022-02-14
上傳用戶：jason_vip1
數字示波器功能強大,使用方便,但是價格相對昂貴。本文以Ti的MSP430F5529為主控器,以Altera公司的EP2C5T144C8 FPGA器件為邏輯控制部件設計數字示波器。模擬信號經程控放大、整形電路后形成方波信號送至FPGA測頻,根據頻率值選擇采用片上及片外高速AD分段采樣。FPGA控制片外AD采樣并將數據輸入到FIFO模塊中緩存,由單片機進行頻譜分析。測試表明:簡易示波器可以實現自動選檔、多采樣率采樣、高精度測頻及頻譜分析等功能。Digital oscilloscope is powerful and easy to use, but also expensive. The research group designed a low-cost digital oscilloscope, the chip of MSP430F5529 of TI is chosen as the main controller and the device of EP2C5T144C8 of Altera company is used as the logic control unit. Analog signal enter the programmable amplifier circuit, shaping circuit and other pre-processing circuit. The shaped rectangular wave signal is sent to FPGA for measure the frequency. According to the frequency value to select AD on-chip or off-chip high-speed AD for sampling. FPGA controls the off-chip AD sampling and buffers AD data by FIFO module. The single chip microcomputer receives the data, and do FFT for spectrum analysis. The test shows that the simple oscilloscope can realize automatic gain selection, sampling at different sampling rates, high precision frequency measurement and spectrum analysis.
上傳時間： 2022-03-27
上傳用戶：
The GL823K integrates a high speed 8051 microprocessor and a high efficiency hardware engine for the best data transfer performance between USB and flash card interfaces. Its pin assignment design fits to card sockets to provide easier PCB layout. Inside the chip, it integrates 5V to 3.3V regulator, 3.3V to 1.8V regulator and power MOSFETs and it enables the function of on-chip clock source (OCCS) which means no external 12MHz XTAL is needed and that effectively reduces the total BOM cost.
上傳時間： 2022-04-27
上傳用戶：qdxqdxqdxqdx
The JW? 7805 is a low noise low-dropout (LDO) voltage regulator with enable function that operates from 1.8V to 5.5V. It provides up to 300mA of output current and offers low-power operation in miniaturized packaging. JW7805 supports fixed output voltage 0.9V, 1.0V, 1.05V, 1.1V,1.2V, 1.3V, 1.35V, 1.5V, 1.8V, 1.85V, 2.1V, 2.2V, 2.3V, 2.5V, 2.6V, 2.7V, 2.8V, 2.85V, 2.9V, 3.0V,3.1V, 3.3V, 3.6V, 4.2V, 4.4V and 5.0V. The features of low quiescent current as low as 6uA and almost zero disable current are ideal for powering the battery equipment. JW7805’s low output noise and high PSRR are also friendly to RF systems.
標簽： JW7805
上傳時間： 2022-05-06
上傳用戶：slq1234567890
低壓差線性穩壓器（Low Dropout Voltage Regulator，LDO）屬于線性穩壓器的一種，但由于其壓差較低，相對于一般線性穩壓器而言具有較高的轉換效率。但在電路穩定性上有所下降，而且LDO有著較高的輸出電阻，使得輸出極點的位置會隨著負載情況有很大關系。因此需要對LDO進行頻率補償來滿足其環路穩定性要求。內容安排上第一節首先簡單介紹各種線性穩壓源的區別：第二節介紹LDO中的主要參數及設計中需要考慮折中的一些問題；第三節對LDO開環電路的三個模塊，運放模塊，PMOS模塊和反饋模塊進行簡化的小信號分析，得出其傳輸函數并判斷其零極點：第四節針對前面分析的三個LDO環路模塊分別進行補償考慮，并結合RT9193電路對三種補償方法進行了仿真驗證和解釋說明。該電路主要包含基準電路以及相關啟動電路，保護電路（OTP，OCP等），誤差放大器，調整管（Pass Element）和電阻反饋網絡。在電路上，通過連接到誤差放大器反相輸入端的分壓電阻對輸出電壓進行采樣，誤差放大器的同相輸入端連接到一個基準電壓（Bandgap Reference），誤差放大器會使得兩個輸入端電壓基本相等，因此，可以通過控制調整管輸出足夠的負載電流以保證輸出電壓穩定。電路所采用的調整管不同，其Dropout電壓不同。以前大多使用三極管來作為穩壓源的調整管，常見的有NPN穩壓源，PNP穩壓源（LDO），準LDO穩壓源，其調整管如圖2所示，其Dorpout電壓分別是：VoRop=2VBE+ Vsr-NPN穩壓源VoRоP =VsurPNP穩壓源（LDO）VDRoP=VE + Vsur-準LDO穩壓源
上傳時間： 2022-06-19
上傳用戶：
