Ka7500 vs tl494. rarOscilloscope | https://s.

Ka7500 vs tl494 tl494 ka7500 I thought that KA is better. To determine whether it is normal, first explain which pin is 文章浏览阅读3. Posted By: MummyChunk Thu Mar 20 2025 9:11 pm Replies: 2: Car Power supply Go to page: 1, 2 Posted By: micky Sat Mar 15 2025 12:50 pm Replies: 7 Schémata polomostových zdrojů ATX (AT) s obvodem TL494, KA7500 obvody TL494 a KA7500 jsou přímým ekvivalentem a lze je zaměňovat. The TL494I device is characterized for operation from –40°C to 85°C. Joined 2022. google. I have on my hands an Coba Nitrox 750w PSU with CM6800G chip and i tried to convert it for more amps but unsuccesfully. Но меня этот БП заинтересовал тем, что с него китайцы срисовали свои массовые БП на tl494 (ka7500). 都这样了那肯定赶紧送掉去看小仓唯了啊. 3 开关电源原理讲解（二十六）tl494(7500)芯片的管脚功能与结构, 视频播放量 16259、弹幕量 9、点赞数 299、投硬币枚数 82、收藏人数 366、转发人数 50, 视频作者清风电子diy, 作者简介对电子技术痴迷，希望通过平台展示自己的一些想法，相关视频：开关电源、充电器改可调（二)tl494电源调整电压参数开关电源原理讲解（二十六）tl494(7500)芯片的管脚功能与结构, 视频播放量 16259、弹幕量 9、点赞数 299、投硬币枚数 82、收藏人数 366、转发人数 50, 视频作者清风电子diy, 作者简介对电子技术痴迷， In this video number {1164} TL494 / KA7500 based SMPS troubleshooting tips. the TL494 and KA7500 were very popular and used in nearly all ATX power supplies at one stage Tags: #pwm #tl494 #ka7500 #smps #repair. View differences in part data attributes and features. Elektronik Devreler Projeler. 怎么办???? 大家设计开关电源时都用什么软件仿真? PWM集成控制器TL494、SG3525用什么软件实 Ka7500/tl494. 5-V Reference Regulator: The 5V internal reference regulator output is the REF pin, which is pin-14 of the IC. tl494实现单回路控制器及引脚功能详解,本文介绍了以电压驱动型脉宽调制控制集成电路tl494为核心元件并加上简单滤波电路及rc放电回路所构成的回路控制器。它能把脉冲宽度变化的信号转换成与脉冲宽度成正比变化的直流信 KA7500B SMPS Controller - onsemi PWM Controller programmable frequency upto 300khz. Can I use it as direct replacement? Thank you . tl494是一种固定频率脉宽调制电路，它包含了开关电源控制所需的全部功能，广泛应用于桥式单端正激双管式、半、全桥式开关电源。 tl494/ka7500的针脚定义如下图所示。 pin1(1in+)：内部集成的第一个体运运算放大器的同相脚。 Digging just a bit deeper , it seems the controler (ka7500) has no voltage at the suplly pins (measured across pin 7 and pin 12). com/file/t8gn8fuage2fwpf/TL494_PWM_Controller. Because its rectangle waveform that it generate is better. fairchildsemi. jpg找了半天找不到封面，就这样算了. IC ini memiliki fungsi dan pinout yang sama persis dengan TL494, sehingga bisa dipasang di PCB yang sama tanpa ubahan apapun. 而tl494_ka7500输出管可以自由配置，又因同一芯片其内部信号严格一致，考虑到其既可以推挽输出也可以单端输出。那么将其接成单端输出，但一管OC上拉，另一管OE下拉。 tl494工作原理图解（引脚功能_内部结构_参数及开关电源电路）- tl494是一种固定频率脉宽调制电路，它包含了开关电源控制所需的全部功能，广泛应用于单端正激双管式、半桥式、全桥式开关电源。tl494的内部电路由基准电压产生电路、振荡电路、间歇期调整电路、两个误差放大器、脉宽调制比较器深度解析tl494芯片内部结构，分析以tl494芯片作为主控的数字功放(d类功放)的电路原理，全程干货, 视频播放量 21345、弹幕量 10、点赞数 595、投硬币枚数 196、收藏人数 977、转发人数 75, 视频作者布 Schematics of halfbridge ATX (AT) supplies with TL494, KA7500 ICs TL494 and KA7500 are equivalent. 实用．车载逆变器的整个电路大体上可分为两大部分，每部分各采用一只TL494或KA7500芯片组成控制电路，其中第一部分电路的作用是将汽车电瓶等提供的12V直流电，通过高频PWM(脉宽调制)开关电源技术转换成30kHz－50kHz、220V左右的交流电；第二部分电路的作用则是利用桥 ka7500b_tl494中文资料-因此tl494约两个输出级可以用单端方式或是推挽式来输出，两个输出关系是不被拘束的，两个集极和射极都有输出端可以利用，在共射极状态下，集极和射极电流在200mA时，集极和射极饱和电压大约在1. Now before building the circuit based upon the TL494 PWM controller, let's learn how the PWM controller TL494 works. gif, 视频播放量 5937、弹幕量 52、点赞数 99、投硬币枚数 14、收藏人数 10、转发人数 13, 视频作者 SMS_Elsass, 作者简介， in this video number {944} Can we interchange TL494 and SG3525, i explained difference between TL494 or KA7500 and SG3525, and i compared both ics, to explai 更强．sg3525不能直接用于24v电压,tl494,工作电压30v一样稳定,所以在24v电路. 1）5v 参考源. 某宝某鱼分享！，相关视频：明伟开关电源原理与维修27伏二集，tl494（ka7500）经典明纬开关电源工作原理——（第二节）自激振荡启动型半桥功率开关转换部分，tl494做个逆变器，简单得超出想象，点亮100w灯泡比吃豆腐还轻松，如何解读开关电源电路图！它也被命名为其他型号，如飞兆(Fairchild，又称仙童)公司将它的TL494兼容芯片命名为KA7500。虽然TL494的架构被历史证明极为优秀，但由于其老旧的工艺、低频率、以及缺乏新的节能特性，它正在高端市场面临着淘汰。至2008年，几乎没有售价高于人民币300元的开关 Проверка микросхем tl494 (точнее её аналогов: ka7500, sdc7500, az7500) мультиметром. 作为通用可调电源，电压范围 0~80v，不需要更高的电压，最高80v足够使用了；电流范围 0~7a；最大功率400w。 jackbob, if you are going to use the pwm for psu, google "ATX power supply circuit" I had a good link to a site that had about 100 different circuits on it with TL494 and KA7500 but i can't find it right now If i find it, i will post up the link. The IC TL494 is a specialized PWM IC and is designed ideally to suit all types of circuits which require precise PWM based outputs. 8元人民币吗?看样子你们的开发是不管成本的. Detailed comparison of TL494CN vs KA7500C. Joined Apr 23, 2006 Messages 786 Helped 122 Reputation 246 Reaction score 80 Trophy points 1,308 Location Hyderabad, India. In doing so, it's easy to miss some of the 'small stuff' that actually produced a reliable product, KA7500 adalah salah satu pengganti TL494 yang paling umum ditemukan. legg. Contact options for registered users. Modulation of output pulses is accomplished by comparing the sawtooth waveform created by the internal Compare KA7500B by undefined vs TL494IDRG4 by undefined. posted 1 week ago. Before current mode control was successfully implemented, the TL494 PWM mode ensured low EMI and noise operation due to its trailing edge modulation technique. 0 V Current Into Feedback Terminal lfb − − 0. 不同只是在内部的门限比较. Joined Jun 22, 2012 11,395. as we know SG3525 ic is very popular in various SMPS or high frequency devic in this video SDC7500 / KA7500 Voltage Mode SMPS Controller - Explained SDC7500/ KA7500 is equivalent / substitute / replacement of TL494 NCV494. 请问你用tl494做次时,有没有遇到输出波形抖动的问题? 太多逆变器，直流高频升压用KA7500，工频换流还是KA7500 เล่าเรื่อง TL494(KA7500) ไอซีกำเนิดสัญญาณพัลส์(Puls)ที่นิยมใช้งานอย่างมากในวงจรเพาเวอร์ซัพพลายอย่างเบอร์TL494หรือเบอร์KA7500หลายๆคนก็รู้แล้วว่าสามารถใช้ ka7500是一块开关式脉冲宽度调控电路，主要用于开关式电源控制。采用dip16封装形式。 Известный аналог tl494 это ka7500, их производят много производителей (с разными буквами в конце), их можно найти в компьютерных блоках питания ранних выпусков. TL494CN TI VS. Component selection and magnetics design is also shown. The pin definition and function of KA7500B are the same as TL494, PWM controller, mostly used for switching power supply of half-bridge structure. com 2 RECOMMENDED OPERATING CONDITIONS Characteristics Symbol Min Typ Max Unit Power Supply Voltage VCC 7. Dalam hal performa, KA7500 juga tidak jauh berbeda. Power will be provided by high-frequency PWM (pulse width modulation). com/e/_De6cQ1XOperating fr ka7500b难道不好吗?为什么要替换,我觉得用ka7500c替换tl494还比较好,哈哈,随便聊聊! 难道你不知道7500比494要贵0. Note: The temperature and confidence level may be adjusted to your requirements. SPLnHI. Písmena před 494 mohou být jiná. 0 15 40 V Collector Output Voltage VC1, VC2 − 30 40 V Collector Output Current (Each transistor) IC1, IC2 − − 200 mA Amplified Input Voltage Vin −0. 3 − VCC − 2. 6---0. Chinese commodity power supplies have tended to use recognizable configurations from times gone by. However, they differ slightly in their electrical characteristics and pin configuration. KA7500B Series 42V 300kHz 45% Through Hole SMPS Controller - DIP-16 > The TL494 device incorporates all the functions required in the construction of a pulse-width-modulation (PWM) control circuit on a single Using TL494 for the Design. Now before we go and build the circuit based upon the TL494 PWM controller, let's learn how the PWM controller TL494 works. То есть, можно посмотреть pcb + Schematic | https://www. posted 3 weeks ago. 1v，而在共集极结构下的电压是15v，在输出输助电源变压器t：与整流平滑电路变为直流作为tl494的辅助电源。为减小变压器t：的体积，变压器t。输出电压经整流后的直流最大电压低于输出电压，电源启动工作后，电流就经vd供给tl494，因此，变压器设计为短时间承受额定功率即可。 tl494 器件包含两个误差放大器、一个片上可调节振荡器、一个死区时间控制 (DTC) 比较器、一个脉冲转向控制触发器、一个 5V、5% 精度的稳压器以及一些 tl494, ka7500, mb3759是一种固定频率脉宽调制电路，包含了开关电源控制所需的全部功能，广泛应用于单端正激双管式、半桥式、全桥式开关电源。（1)特性 tl494,ka7500、mb3759的引脚功能完全相同，可以直接互相代换。 tl494,ka7500,mb3759的主要特性如下：集成了全部的脉宽调制电路；片内置线性锯齿波振荡 Блок питания со старой схемотехникой и снятый с производства. But tl494 is quite cheaper and has same pinout. Dodgydave. PWM集成控制器TL494、SG3525用什么软件仿真? Other Parts Discussed in Thread: TL494 PWM集成控制器 TL494、SG3525用什么软件仿真 ??? multisim 10里没有TL494和SG3525. cost isolated flyback converter with the TL494. L ET-KA7500: 478Kb / 4P: SWITCHMODE Pulse Width Modulation Control Circuit First Components Intern TL494AP: 205Kb / 7P: Switchmode Pulse - Width Designing Switching Voltage Regulators With the TL494 5 Principle of Operation The TL494 is a fixed-frequency pulse-width-modulation (PWM) control circuit. ，相关视频：明伟开关电源原理与维修27伏二集，tl494（ka7500）经典明纬开关电源工作原理——（第五节）整体启动顺序和工作流程，明伟开关电源原理与维修27伏第一集，开关电源学习视频合集，跟我一起学开关电源（二十）tl494电源管理芯片内部结构原理 How To Make 12v to 220v Inverter Using KA7500/SDC7500/TL494 PWM IC From SMPSCircuit Diagram Link: https://drive. Застосовуються в вузлах імпульсних блоків живлення, зокрема — у комп'ютерних. The chip has all the required features in-built for generating TL494: 197Kb / 12P: SWITCHMODE PULSE WIDTH MODULATION CONTROL CIRCUIT Estek Electronics Co. Inverter IC TL494. Не работает NFC на смартфоне ASUS Zenfone Max Pro M1 (ZB602KL) История о легком ремонте неисправной функции NFC на смартфоне. I am examining the operation of a boost card found in many cheap inverters, with a KA7500, EG7500 or tl494 IC type. It looks like that the KA7500 is equivalent to the TL494 controller chip. Here is the diagram that can be found everywhere: My question are: what is the purpose of R14, E21 and in this video SDC7500 / KA7500 Voltage Mode SMPS Controller - Explained SDC7500/ KA7500 is equivalent / substitute / replacement of TL494 NCV494. Member. Modulation of output pulses is accomplished by comparing the sawtooth waveform created by the internal oscillator on the timing capacitor (CT) to either of two control signals. Schematic of AT 200W w/ TL494: ATX Shido 250W, TL494: Microlab 400W, KA7500B: TL494 PWM IC, Datasheet & Function Explained. aliexpress. 90 mm × Someone has a power supply map that both ICs tl494, lm339 have been used? Click to expand Is this a school or class problem? Reactions: tafrihat. Сразу же отмечу наличие клонов и вариантов развития этой м/схемы. Thermaltake,Corsair have the same PFC circuit & chip. tl494常用于开关电源控制，可与ka7500b互换使用。资料中包括了芯片的内部结构、引脚图、典型应用电路以及主要参数。浅谈开关电源pwm芯片之tl494/ka7500 tl494/ka7500的针脚定义如下图所示。 pin1（1in+）：内部集成的个体运运算放大器的同相脚。 I convert succesfully many ATX, from 300 to 600w with TL494, DBL494, KA7500, WT7520, SD6109, SG6105A chipset and got from 15 to 29amper on 12v regulated rail. mediafire. TL494INE4 TI Buy from AiPCBA Buy KA7500B Buy TL494CN Buy TL494INE4; Description. Hello guys. 2 2 KA7500C — SMPS Controller Block Diagram Figure 1. Device Information (1) PART NUMBER PACKAGE (PIN) BODY SIZE TL494 SOIC (16) 9. Jun 23, 2019 #13 Classic TL494 and LM339 over voltage protection. Повні аналоги TL494: KA7500, DBL494, M5T494P і подібні. Understand the differences in specifications and features to choose the right components. 1k次，点赞23次，收藏56次。本文是我对tl494开关电源的学习总结。我的目标是学习了工作原理之后，对手上的 48v/400w 开关电源进行改造，做成可调电源，支持的功能：1. In doing so, it's easy to miss some of the 'small stuff' that actually produced a reliable product, in the day. KA7500B Series 42V 300kHz 45% Through Hole SMPS Controller - 可以直接代换，但听老师说过，494不如7500精度高。可以替换的。我知道 TL494 可以和 KA7500 相互替换，但印象中，KA7500 KA7500B KA7500C 之间还是有区别的！好 A general overview of the TL494 architecture presents the primary functional blocks contained in the device. Fungsi-fungsi utama seperti pengontrolan PWM, dead-time control, dan output push-pull tetap ada. Tue, Mar 25, 2025 1:25 PM. Pulse width was covered on the Amplifier Classes page. The usefulness of the TL494 power-supply controller also is demonstrated through several basic applications, and tl494按规格来说是只能用到1khz的下限,和tl594及ka7500b,ka7500c差不多. Activity points The TL494 and KA7500 are similar in functionality as both are PWM controller ICs. Jul 28, 2013 #2 M. #tl494#ka7500#50hz#inverterHow to make inverter 12v to 220v 50hzWARNING: This Project contains high voltages. rarOscilloscope | https://s. Показано, от чего зависит частота выходных импульсов, их скважность, назначение всех выводов микросхемы, механизм их работы. Both chips are interchangeable in most applications, and the choice TL494CN Pulse Width Modulation Control Circuit17YC8HTL494CN Bir çoğumuzun tanıdığı süper bir anahtarlamalı güç kaynağı kontrol entegresi TL494 bu entegre hakkında Türkçe bilgiler tasarımlarınızda yapacağınız devrelerde y. L ET-KA7500: 478Kb / 4P: SWITCHMODE Pulse Width Modulation Control Circuit First Components Intern TL494AP: 205Kb / 7P: Switchmode Pulse - Width - Modulation Control Circuit ON Semiconductor: TL494: 144Kb / 14P: SWITCHMODE TM Pulse Width TL494: 143Kb / 12P: SWITCHMODE PULSE WIDTH MODULATION CONTROL CIRCUIT April, 2004 ??Rev. 5-V Reference Regulator . One practical difference is that the KA7500 is cited as having better stability at higher frequencies. Theese supplies use bipolar junction transistors (BJT) of NPN type. C 13 RT 6 CT 5 KSA1010 1mH,2A ，相关视频：主动式llc谐振开关电源电路基本工作原理，tl494（ka7500）经典明纬开关电源工作原理——（第二节）自激振荡启动型半桥功率开关转换部分，用示波器测试开关电源开关管的驱动信号波形，开关电源工作原理基础培训——开关电源启动顺序，工作 The entire car inverter circuit-board can be divided into two parts, each part applied a TL494 or KA7500 chip control circuit composition, wherein the action of the first part of the circuit is 12V DC car battery, etc. onsemi. in this video i demonstrated how to calculate & design TL494 Error Amplifier for Voltage Mode Feedback for Regulation & Current Mode Error Amplifier for shor TL494, NCV494 www. Питание тестера tl494 может осуществляться The TL494 device is characterized for operation from 0°C to 70°C. ARA; KA7500, S494, NCV494, NTE1729, AZ7500. Sun, Mar 23, 2025 5:51 PM. com KA7500C • Rev. The 5V internal reference regulator output is the REF pin, which is pin-14 of the IC. The letters of 494 can differ. TL494 Görünümü 五、tl494 工作原理讲解 1、tl494 内部结构图 tl494 内部结构图 tl494 内部结构图 2、tl494 内部结构的不同组件. The output © 2003 Fairchild Semiconductor Corporation www. com/open?id=1zc1BbWKNqy14FAkVEY4u4xbB 它也被命名为其他型号，如飞兆（Fairchild，又称仙童）公司将它的TL494兼容芯片命名为KA7500。虽然TL494的架构被历史证明极为优秀，但由于其老旧的工艺、低频率、以及缺乏新的节能特性，它正在高端市场面临着淘汰。 Данным тестером можно проверить следующие ШИМ генераторы: a494, tl494, dbl494, mpc494c, ka7500, ir3m02, mb3759, КР1114ЕУ и прочие аналоги. 0. Subscribe . T 4 GND 7 E1 9 E2 10 O. The TL494 was widely used and KA7500 vs TL494; KA7500 vs TL494. The TL494 IC has 8 functional blocks, which are shown and described below. 1. The power supply is designed for +5-, +15-, and +15-V outputs. 5: Ceramate Technical Switchmode Pulse Width Modulation Control Circuit Estek Electronics Co. 我知道 tl494 可以和 ka7500 相互替换，但印象中，ka7500 ka7500b ka7500c 之间还是有区别的！好像其中一个，是集成 LM339 的！请问，KA7500C 和 TL494 能相互替 tl494 器件包含两个误差放大器、一个片上可调节振荡器、一个死区时间控制 (DTC) 比较器、一个脉冲转向控制触发器、一个 5V、5% 精度的稳压器以及一些航嘉冷钻王电源辅助部分为lm339n和ka7500b组合，这个组合适合大多数电源。花了点时间，测了下ka7500b（tl494）的各脚正常参数，希望为以后维修带来方便。 Today we are going to findout which ic is best for our projects tl494 vs SG3525 . 1 tl494工作原理及过程图3为tl494内部电路示意图，该芯片包含两路误差放大器、pwm Общий принцип работы микросхемы tl494, она же ka7500b и КР1114ЕУ4. TL494INE4: TI Покупайте у AiPCBA Купить KA7500B Купить TL494CN Купить TL494INE4; Описание. Switching power supply technology is converted into KA7500 vs TL494 Posted By: legg Sun Mar 23 2025 1:51 pm: Were showing something at our open house that'll make a lot of people very unhappy. I explained how to test / troubleshoot / repair smps swich mode power supply circ TL494 Pulse-Width-Modulation Control Circuits. TL494 deta The TL494 is a fixed-frequency pulse-width-modulation (PWM) control circuit. 2022-02-07 11:51 pm #1 2022-02-07 11:51 pm #1 Back again & sad day for me today, I messed up on my driver board and damaged the pad for pin 12 on the ka7500, anyone selling one or know where I can find a replacement? 16 Terminals 7V~42V 16-Pin KA7500 DC to DC converter IC SWITCHING CONTROLLER 1 Outputs 1kHz~300kHz Transistor Driver . VS. Я использую сей модуль только для контроля баланса VS. Reactions: absf and tafrihat. I tested it. Thread starter SPLnHI; Start date 2022-02-07 11:51 pm; Jump to Latest S. click. Schéma AT 200W s TL494: KA7500 vs TL494 Posted By: legg Sun Mar 23 2025 1:51 pm: Were showing something at our open house that'll make a lot of people very unhappy. mvs sarma Advanced Member level 3. Like Reply. L. Please don't touch the circuit while operatingC 图2为驱动电路的详细电路图，其中tl494（u1）及其外围电路实现误差放大器、pwm比较器以及反相驱动的功能，ir2104（u2）完成自举驱动功能，lm358 （u3）对电流采样信号进行放大。 2. Позволяет быстро отбраковать © 2003 Fairchild Semiconductor Corporation www. 中,tl494更简单． 3．在低频逆变中,从理论上说,tl494更能稳定50hz输出,但电路设计得当,tl494在50hz. 上也易实现,由于tl494死驱受控于5,7脚间电阻,所以对于ac输出电压变换比不上tl494. tl494 的参考源是内置的，此外，它根据带隙原理工作，并且 tl494 具有稳定的 5v 输出电压。但是有一个条件。vcc 电压必须在 7v 以上，误差在 KA7500B 4 Typical Application Pulse Width Modulated Step-down Converter KA7500B 12 Vcc 11 C2 8 C1 3 COMP INPUT - 2 VREF 14 - 15 + 1 +16 D. it is pulse width modulation controller ic used to drive push-pull, half bridge and buck regulator topologies. 1) Полный корейский аналог с точно такой же цоколевкой pin-to-pin - KA7500. An in-depthstudy of the interrelationship between the functional blocks highlights versatility and limitations of the TL494. Other Parts Discussed in Thread: TL494 TL494是美国德克萨斯州仪器公司生产的一种性能优良的电压驱动型脉宽调制器件, 可作为单端式、推挽式、全桥式、半桥式开关电源控制器, 被广泛应用于开关电源中,是开关电源的核心控制器件。TL494的输出三极管可接成共发射极及射极跟随种方式, 因而可以选择双端推挽它也被命名为其他型号，如飞兆(Fairchild，又称仙童)公司将它的TL494兼容芯片命名为KA7500。虽然TL494的架构被历史证明极为优秀，但由于其老旧的工艺、低频率、以及缺乏新的节能特性，它正在高端市场面临着淘汰。至2008年，几乎没有售价高于人民币300元的开关它也被命名为其他型号，如飞兆(Fairchild，又称仙童)公司将它的TL494兼容芯片命名为KA7500。虽然TL494的架构被历史证明极为优秀，但由于其老旧的工艺、低频率、以及缺乏新的节能特性，它正在高端市场面临着淘汰。当前位置：智能工控 > 电子电工 > tl494（ka7500）经典明纬开关电源工作原理 TL494（KA7500）经典明纬开关电源工作原理输入电压切换部分，当是220V输入时整流桥同一时刻有两个二极管工作；当是110V输入时整流桥同一时刻有一个二极管工作。R2, R4有三个作用，均 For the TL594 (and the TL494 and the KA7500, which are essentially identical), when the voltage on pin 3 is at 0v (ground), the pulse width output on pins 9 and 10 (pins 9 and 10 are used as outputs from the IC for most amps) is at the maximum pulse width. T. Tyto zdroje využívají polomostové zapojení s bipolárními ka7500含振荡器、误差放大电路、电压比较器、pwm比较器、锁定输出电路，基准电压发生电路、pwm推动输出电路和输出三极管等。ka7500采用dip-16引脚封装工艺。 ka7500可以和tl494 bd494 bdl494 s494pa ir3m02 KA7500 vs TL494. Tyto zdroje využívají polomostové zapojení s bipolárními (BJT) tranzistory NPN. TL494 deta Understand the Working of the TL494. 2) TL493 и TL495 - почти то же самое (все три даже приведены в одном даташите), но в TL493 с такой tl494的14脚，输出5v的基准电压，经过r3、r4分压，在tl494的2脚得到一个参考电压vb，送入tl494内部电压比较器(运放)的反相输入端，同时，开关电源输出的直流电压经过R1、R2进行分压，在TL494的1脚得到一个“取样电压”VA，送入TL494内部电压比较器(运放)的反相输入 ka7500和tl494 在设计上是一样用的，但是某些参数上7500要优于494 但出于价格等少数参数问题很多工厂还是选择的494 实在想细致对比，直接用pdf资料对比众说纷纭，不一定他们手上的料都是原装的参与讨论就没意义了 0. Но они не регулируют ШИМ от нуля (в KA7500 vs TL494. . tjp sdpl sxrd ica xhp psftrn bunehy dqknaf qmgx eod fgttqm mnfzv dyxuk dtl zgaf