摘要
介绍了一种带频率抖动功能的振荡器,该振荡器结构简单、频率抖动效果明显,通过周期性改变振荡器内部比较器的比较阈值达到频率抖动的效果,可有效降低芯片电磁干扰。使用0.5μm BCD工艺对电路进行仿真,在25℃,TT工艺角下,振荡器中心频率为66.87kHz,频率抖动差值为±5.02kHz,频率抖动重复频率约为1.046kHz。电路适用于对电磁兼容性要求较高的开关电源芯片,具有很强的工程实用性。
A simple and effective oscillator circuit with frequency jittering was designed. With frequency jittering, which was achieved by periodically changing threshold voltage of the comparator, this oscillator could reduce electromagnetic interference effectively. Simulation based on 0. 5 μm BCD process showed that, at 25 ℃ ambient temperature and typical process corner, the oscillator had a center frequency of about 66. 87 kHz, a frequency jittering range of about ±5. 02 kHz, and a repetitive frequency of about 1. 046 kHz for frequency jittering. The circuit is suitable for switching power supply IC that requires higher electromagnetic compatibility.
出处
《微电子学》
CAS
CSCD
北大核心
2013年第4期529-532,536,共5页
Microelectronics
关键词
振荡器
频率抖动
电磁干扰
开关电源
Oscillator
Frequency jittering
EMI
Switching power supply
