低抖動Q開關(guān)光電轉(zhuǎn)換及觸發(fā)系統(tǒng)設(shè)計

　　“Z-Pinch”裝置對其激光觸發(fā)氣體閉合開關(guān)有嚴格時序要求。為實現(xiàn)四倍頻 Nd : YAG激光器出光時刻的精確控制，開展了激光器Q開關(guān)光電轉(zhuǎn)換及觸發(fā)系統(tǒng)的研究。采用AVAGO公司的高速光電轉(zhuǎn)換器件AVAGO2316TZ，將接收到的光信號轉(zhuǎn)換成模擬電壓信號，并以PECL(positive emitted-couple-logic)電平形式實現(xiàn)該電信號的板級傳輸與處理，最終，該信號作為IXYS公司的IXDD415的控制端，以實現(xiàn)低抖動，快前沿的電脈沖輸出用以驅(qū)動Q開關(guān)。電路中采用了電感、電容、RC網(wǎng)絡(luò)濾波方法，有效減小電源噪聲對抖動的影響。該光電轉(zhuǎn)換及觸發(fā)系統(tǒng)在Z裝置單路樣機中得到應用，測試結(jié)果表明均方根抖動為70 ps，時延極差<1 ns。

　　Abstract:

　　“Z-Pinch” devices have strict timing requirements on the laser triggered gas closed switches. In order to trigger accurately control the Nd : YAG laser， a low jitter optic-electricity signal transfer and Q-switch trigger system was studied. Optic-electricity signal was transfered into analog voltage signal by AVAGO2316TZ，and the analog signal was transmitted and handled in the form of PECL. At last， the signal was connected with input pin of IXDD415. The output pulse of IXDD415 has characteristic of low jitter and fast rise phase. Inductance, capacitance and RC network filter were used in the circuit, which effectively reduced the jitter influence. This system is applied to Z device simplex prototype. The results testify that the RMS jitter is about 70ps，the range of jitter is less than 1ns.