An Accurate 1.08GHz CMOS LC Voltage-Controlled Oscillator

An accurate 1.08GHz CMOS LC voltage-controlled oscillator is implemented in a 0.35μm standard 2P4M CMOS process.A new convenient method of calculating oscillator period is presented.With this period calculation technique,the frequency tuning curves agree well with the experiment.At a 3.3V supply,the LC-VCO measures a phase noise of -82.2dBc/Hz at a 10kHz frequency offset while dissipating 3.1mA current.The chip size is 0.86mm×0.82mm.

自行车上锁提醒器

文介绍的这种提醒器只用了一片集成电路和少量元件,线路简单、使用方便。此提醒器安装在自行车上,当车主人停车忘了上锁时,会自动发出上锁告警声,以免自行车丢失造成损失。 工作原理:线路如图1所示。与非门1、2及R3、C2,门3、4及R4、C3分别构成两个可控振荡器。后一个振荡器受前一个可控振荡器的控制,而前一个振荡器起振与否取决于A点的状态。S1、S2为二只微动型开关,当S1、S2中任一只开关断开时,A点电位由电阻R2偏置在低电平,振荡器停振,当S1、S2均接通时,A点为高电平,振荡器开始振荡。