一种用于开关电源的多模式振荡器  

A Multi-Mode Oscillator for DC-DC Converters

作　　者：李卓[1] 岳素格[1] 莫艳图[1] 宋奎鑫 初飞[1] 

机构地区：[1]北京微电子技术研究所,北京100076

出　　处：《微电子学》2017年第3期375-378,共4页Microelectronics

摘　　要：基于0.25μm BCD工艺,设计了一种应用于开关电源的多模式环形振荡器,具有结构简单、三种模式可选、可修调的特点。电路通过模式切换生成可调电流的方式对电容充放电,产生不同频率的斜坡及方波信号。测试结果表明:在-40℃~125℃温度范围内,振荡器主振荡模式输出范围为483.9~518.6kHz,与固定频率(500kHz)的最大偏移率为3.72%,电阻频率调节模式输出范围为25kHz^2.5 MHz,同步模式下可调同步频率范围为40kHz^4 MHz。目前,该振荡器已被成功应用于一种DC-DC开关电源芯片中。A multi-mode ring oscillator for DC-DC converters was designed in a 0.25 μm BCD process. The oscillator featured simple structure, optional triple-mode and trimming function. By switching the modes to adjust the charging current, the circuit created different frequency ramp signals and square waves. The test results showed that in the master mode, the frequency changed from 483.9 kHz to 518.6 kHz, and the maximum offset （from the fixed frequency） was 3. 720/00 at the temperature range of -40 ℃ - 125 ℃. In the resistance frequency regulation mode, the frequency could be adjusted from 25 kHz to 2.5 MHz. In external synchronization mode, the synchronous frequency could cover from 40 kHz to 4 MHz. At present, this high performance oscillator has been successfully applied in a DC-DC converter.

关 键 词：多模式 电阻频率调节 外部时钟同步 修调 

分 类 号：TN433[电子电信—微电子学与固体电子学] TN752