le flows through MOS channel while Ih flows across PNP transistor Ih= a/(1-a) le, IE-le+lh=1/(1-a)' le Since IGBT has a long base PNP, a is mainly determined by ar si0 2ar= 1/cosh(1/La), La: ambipolar diff length a-0.5 (typical value)p MOSFET channel current (saturation), le=U"Cox"W(2"Lch)"(Vc-Vth)le Thus, saturated collector current Ic, sat=1/(1-a)"le=-1/(1-a)"UCox"W/(2Lch)"(Vo-Vth)2Also, transconductance gm, gm= 1/(1-a)"u' Cox W/Lch*(Vo-Vth)Turn-On1. Inversion layer is formed when Vge>Vth2. Apply positive collector bias, +Vce3. Electrons flow from N+ emitter to N-drift layer providing the base current for the PNP transistor4. Since J1 is forward blased, hole carriers are injected from the collector (acts as an emitter).5. Injected hole carriers exceed the doping level of N-drift region (conductivity modulation). Turn-Off1. Remove gate bias (discharge gate)2. Cut off electron current (base current, le, of pnp transistor)
標簽： igbt
上傳時間： 2022-06-20
上傳用戶：wangshoupeng199
摘要：本文在分析1GBT的動態開關特性和過流狀態下的電氣特性的基礎上，通過對常規的IGBT推挽驅動電路進行改進，得到了具有良好過流保護特性的IGBT驅動電路。該電路簡單，可靠，易用，配合DSP等控制芯片能達到很好的驅動效果Abstract：Based on the studies on the dynamic switching and over-current characteristics of IGBT，this paper makes some improvments to the original push-pull driving circuit，obtains a new IGBT driving circuit which has a good over-current protection function.The circuit is simple，reliable and easy to use.Combined with controlling chips such as DSP it will do a great job in driving applications.關鍵詞：IBGT：開關特性；驅動；過流保護；Key Words:IGBT；switching characteristics；driving:over-current protection
上傳時間： 2022-06-21
上傳用戶：
文章首先闡述了整個方案的工作原理，給出LDO設計的指標要求；其次，依據系統方案的指標要求和制造1藝約束，實現包含誤差放大器、基準源和保護電路等了模塊在內的電壓調整器：此外，文章還著重探討了“如何利用放大器驅動100pF數量級的大電容負載"的問題；最后，給出整個模塊總體電路的仿真驗證結果。LDO的架構分析和設計以及基準源的設計是本文的核心內容。在LDO架構設計部分，文章基于對三種不同LDO拓撲的分析，選擇并實現了含緩沖器級的LDO./設計中通過改進反饋網絡，采用反饋電容，實現對LDO的環路補償。同時，為提高誤差放大器驅動功率管的能力、適應LDO低功耗發展的需求，文章探討了如何使用放大器驅動大負載電容的問題，基于密勒定理和根軌跡原理，本文通過研究密勒電容的作用，采用MPC（Miller-Path-Compersation）結構，實踐了兩級放大器驅動大負載電容的方案，并把MPC補償技術推廣到三級放大器的設計中。文章設計的CRF（CRF：Current Re ference controlled by Feedback）電流基準是基于對傳統自啟動基準電流源的改進實現的。CRF基準電流源架構中存在一條阻性的電流道路，確保其在加載電源電壓的過程中能夠實現快速啟動，響應速度達到1ps：而傳統自啟動基準電流源在相同的設計參數下，響應速度長達120us.CRF基準電流源突破了響應速度對其應用的限制。
上傳時間： 2022-06-23
上傳用戶：
開關升壓型鋰電池充電管理芯片FLD5302/3概述 為開關型兩節或三節鋰離子/鋰 聚合物電池充電管理芯片，非常適合于便攜 式設備的充電管理應用。 集電壓和電 流調節器、預充、充電狀態指示和充電截止 適配器自適應等功能于一體，采用 SOP-8 封裝。 對電池充電分為三個階段：預 充（ Pre-charge ）、恒流（CC/Constant Current）、恒壓（CV/Constant Voltage）過程。 集成過壓及過流保護，確保電芯的 安全。
上傳時間： 2022-06-25
上傳用戶：
本應用筆記介紹一種采用dsPIC數字信號控制器（Digital Signal Controller，DSC）或PIC24單片機來實現無刷直流（Brushless Direct Current，BLDC）電機無傳感器控制的算法。該算法利用對反電動勢（Back-Electromotive Force，BEMF）進行數字濾波的擇多函數來實現。通過對電機的每一相進行濾波來確定電機驅動電壓換相的時刻。這一控制技術省卻了分立的低通濾波硬件和片外比較器。需指出，這里論述的所有內容及應用軟件，都是假定使用三相電機。該電機控制算法包括四個主要部分：·利用DSC或單片機的模數轉換器（Analog-to-Digital Converter，ADC）來采樣梯形波BEMF信號·PWM導通側ADC采樣，以降低噪聲并解決低電感問題·將梯形波BEMF信號與VBUS/2進行比較，以檢測過零點·用擇多函數濾波器對比較結果信號進行濾波·以三種不同模式對電機驅動電壓進行換相：-傳統開環控制器·傳統閉環控制器比例-積分（Proportional-Integral，Pl）閉環控制器
標簽： BLDC
上傳時間： 2022-07-01
上傳用戶：
The GD32F103xx device is a 32-bit general-purpose microcontroller based on the ARM?Cortex?-M3 RISC core with best ratio in terms of processing power, reduced power consumption and peripheral set. The Cortex?-M3 is a next generation processor core whichis tightly coupled with a Nested Vectored Interrupt Controller (NVIC), SysTick timer and advanced debug support.The GD32F103xx device incorporates the ARM ' Cortex?-M3 32-bit processor core operating at 108 MHz frequency with Flash accesses zero wait states to obtain maximumefficiency. It provides up to 3 MB on-chip Flash memory and up to 96 KB SRAM memory. An extensive range of enhanced I/Os and peripherals connected to two APB buses. The devices offer up to three 12-bit ADCs, up to two 12-bit DACs, up to ten general-purpose
標簽： gd32f103
上傳時間： 2022-07-23
上傳用戶：aben
Single-Channel, Serial Input, 4 mA to20 mA, Current Source DAC, HART Connectivity
上傳時間： 2022-07-24
上傳用戶：
STM32F驅動L6470 ■ Operating voltage: 8 - 45 V■ 7.0 A out peak current (3.0 A r.m.s.)■ Low RDS(on) Power MOSFETs■ Programmable speed profile and positioning■ Programmable power MOS slew rate■ Up to 1/128 microstepping■ Sensorless stall detection■ SPI interface■ Low quiescent and standby currents■ Programmable non-dissipative overcurrentprotection on high and low-side■ Two levels of overtemperature protection
標簽： l6470
上傳時間： 2022-07-25
上傳用戶：kingwide
?This is a high sensitivity type of Nicera Hall element using evaporated InSbfilm.?It performs effectively in low magnetic fields due to the high sensitivity.?The input and output resistance values are suitable for transistor circuitsBrushless motors?DVD drive, CD-ROM drive, floppy disk drive?Other small precision motors?Non-contacting magnetic sensors?Position sensors, rotation sensors, current sensors?Magnetic flux sensors other than those above
標簽： nhe520f
上傳時間： 2022-07-26
上傳用戶：
This is a high sensitivity type of Nicera Hall element using evaporated InSbfilm.It performs effectively in low magnetic fields due to the high sensitivity.The input and output resistance values are suitable for transistor circuits.Sip type packageApplications Brushless motorsPosition sensors, rotation sensors, current sensorsNon-contacting magnetic sensorsCurrent sensorsMagnetic flux sensors other than those above
上傳時間： 2022-07-26
上傳用戶：
