應用於高速電路測試之前端放大器電路設計

Abstract

隨著數位電路操作速度的提升，量測系統的規格也必須跟進以符合趨勢，包括操作頻寬、動態範圍、線性度等，而量測系統中前端放大器電路設計是其中一個必須突破的關鍵零組件。在本論文中，針對寬頻、直流耦合、高線性度等規格特性，學生提出了DC到1 GHz高輸出擺幅驅動電路設計與DC到5 GHz直流耦合可調增益放大器設計。 高壓驅動電路設計可分成兩個部分，放大級使用Win GaN 0.25 μm pHEMT製程實現，緩衝級使用TSMC 0.18 μm BCD CMOS製程實現，最後透過異質整合的方式利用鎊線整合於PCB板上，此電路可應用於全自動可測試系統中的前端放大器。量測結果，整合電路最大操作速度約200 MHz，輸出擺幅範圍約3.13 V。 直流耦合可調增益放大器的部分，使用TSMC SiGe 0.35 μm HBT製程實現，此電路可提供DC到5 GHz寬頻的可調增益功能。量測結果，小訊號可調增益為-22 ~ 41 dB、輸入壓縮點(P1dB)為-41 ~ 8 dBm、雜訊指數(NF)為16 ~ 34 dB，直流功率消耗為1040 mW。

As the increasing of digital circuits’ speed, the specifications of measurement system must be also improved, including bandwidth, dynamic range and linearity. The front-end amplifier design is one of the most important techniques in measurement system, which is needed to overcome. In this thesis, we will focus on characteristic of wideband, DC coupling and high linearity. A DC to 1 GHz high output swing driver and a DC to 5 GHz DC-coupled variable gain amplifier are proposed. DC to 1 GHz high output swing driver has two parts. Amplify stage is designed and implemented in Win GaN 0.25 μm pHEMT technology and buffer stage in TSMC 0.18 μm BCD CMOS technology. Finally we use bondwire to combine with the both circuits in PCB board, which is the concept of System in Package(SIP). The Driver circuit can be used as front-end amplifier in Automatic-test-equipment (ATE). From the measurement results, the maximum speed of integrated version is about 200 MHz. The total output swing range is about 3.13 V. Variable gain amplifier (VGA) is designed and implemented in TSMC SiGe 0.35 μm HBT technology. The VGA provides DC to 5 GHz bandwidth and tunable gain. From measurement results, the tunable gain is -22 ~ 41 dB. P1dB is -41 ~ 8 dBm. The noise figure is 16 ~ 34 dB. The total DC power consumption is 1040 mW.