AC/DC 与隔离式DC/DC 电源- PWM 与谐振控制器- UC2842

说明:

UC1842/3/4/5的家庭控制设备提供了必要的功能来实现脱机或直流对直流固定频率电流型控制方案具有最小外部零件数。在内部实现电路包括低压闭锁展示启动电流小于1 mA,精密参考削减准确性在误差放大器输入,逻辑来确保锁住操作,一个PWM比较器也提供了限流控制,和一个图腾柱输出级设计源

The UC1842/3/4/5 family of control devices provides the necessary features to implement off-line or dc-to-dc fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include under-voltage lockout featuring start up current less than 1 mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off state.

Differences between members of this family are the under-voltage lockout thresholds and maximum duty cycle ranges. The UC1842 and UC1844 have UVLO thresholds of 16 VON and 10 VOFF, ideally suited to off-line applications. The corresponding thresholds for the UC1843 and UC1845 are 8.4 V and 7.6 V. The UC1842 and UC1843 can operate to duty cycles approaching 100%. A range of zero to 50% is obtained by the UC1844 and UC1845 by the addition of an internal toggle flip flop which blanks the output off every other clock cycle

特性:

优化了脱机和直流对直流转换器
　　低的启动电流(< 1 mA)
　　自动进料ForwardCompensation
　　脉冲,脉冲电流限制
　　增强负载响应特性
　　欠压锁定与滞后
　　双脉冲抑制
　　高电流图腾柱输出
　　内部装饰带隙基准
　　500千赫操作
　　低RO误差放大器的修剪准确性误差放大器输入,逻辑来确保锁住操作,一个PWM比较器也提供了限流控制,和一个

Optimized For Off-line and DC-to-DC Converters
Low Start-Up Current (<1 mA)
Automatic Feed ForwardCompensation
Pulse-by-Pulse Current Limiting
Enhanced Load Response Characteristics

Under-Voltage Lockout With Hysteresis
Double Pulse Suppression
High Current Totem Pole Output
Internally Trimmed Bandgap Reference
500-kHz Operation
Low RO Error Amp

参数：

框图：

深圳市广辉电子有限公司是国内实力的电子元器件代理分销商和现货库存供应商之一。 广辉电子代理经销的产品有：IC集成电路、继电器、传感器、贴片电容、贴片电阻、贴片电感、贴片磁珠、贴片二、三极管、集成电路。代理经销的品牌有: TDK、MURATA 、PANASONIC、TAIYO、NICHICON、NEC、YAGEO、WALSIN、RALEC、AVX、KEMET、SPRAGUE、PARTSNIC、Intel、Motorola、Sharp、Sony、Samsung、 Sanyo、 Siemens、Maxim、Harris、Hyundai、National、Fairchild、Philips、Toshiba、Catalyst、 Winbond. 我司供应贴片与插件钽质电容，贴片电容；同时在偏冷门、军工、停产、紧缺料、断档、急料类电子元器件也具备相当优势！除有大量现货库存外，我们还与国内外数千家OEM、EMS厂家及现货商联网，可将库存直接呈现在您的眼前！从定单到交货，最快可在48 小时内将急需的货物送到您的手中，从而可以使您早日将产品推出市场，抢占先机！！ 本公司一惯坚持：“品质、价格合理、交货快捷、服务至上”的发展理念，始终将“诚信、认真、执着、乐观”的精神作为企业发展的宗旨，通过强大的市场服务网络体系向客户提供规范化、化、多元化、全方位的优质服务。真诚欢迎海内外客户前来洽谈合作，共谋发展和建立长期的合作关系！同时也希望能与电子界的同行进行广泛的交流合作，共同为业界的繁荣发展作出应有的贡献！