一种高速高灵敏度的光电耦合器

High-speed and High-sensitivity Optical Coupler

研制了一种高速高灵敏的光电耦合器芯片,其中含有以Nwell-Pepitaxial-Psubstrate为模型的光电探测器(PD)、跨阻运放(TIA)以及后续的处理电路。详细分析了PD的模型,并对其频率响应做了理论推导和仿真,设计了跨导运放的电路,并对其进行了仿真验证。实测结果表明,当光电流为12.2mA时,TIA模块的灵敏度可达2ns,整片的响应时间为205ns和155ns。该光电耦合器适用于高速、高灵敏度的智能控制仪器及通信系统。

Designed and fabricated is a monolithically integrated high-speed and high- sensitivity optical coupler chip, which contains N-well-P-substrate model for the photoelectric detector （PD）, the transimpedance amplifier （TIA） and the subsequent processing circuits. The PD model was analyzed and its frequency response was simulated, then operational transconductance amplifier （OTA） circuit was designed. The experimental results show when the temperature is 25 ℃ and the optical current is 12.2 mA, the sensitivity of the TIA module can reach 2 ns, and the response time of the entire chip is 205 ns and 155 ns. So it is suitable for high- speed and high-sensitivity intelligent control instruments and communication systems.