GaN基APD日盲紫外探测器读出电路设计

ROIC Design for Visible-Blind Ultraviolet GaN APD

基于GaN基APD（雪崩二极管）日盲紫外探测器工作原理,我们设计了GaN-APD日盲紫外探测器的读出电路（ROIC）。考虑到GaN-APD日盲紫外探测器的特性,我们重点研究了80 V高压击穿保护电路、暗电流消除电路以及为CTIA运放电路的电流偏置电路和带隙基准电路。在此基础上,我们设计了1×8的电路并进行了仿真验证,读出电路耐高压不小于80V,当积分电容为4 pF,积分时间为25μs,时钟频率为100 kHz的时候,电路的电荷存储能力为5.6×107个,输出电压摆幅在0~2.25 V,读出电路的输出电压线性度不低于99%。

Based on the operating principle of the visible-blind ultraviolet GaN APD（ Avalanche Photodiode Diode）,the characteristic of the breakdown voltage protection,dark current cancellation and the current biasing circuit and bandgap reference voltage circuit of CTIA are investigated. Designed and simulated a 1 × 8 ROIC（ Readout Integrated Circuit）,the simulation results show that ROIC has characteristic of high voltage protection（ 80 V）. The circuit under100 kHz provides a maximum charge storage capacity of 5. 6 × 107 electrons for a 4 pF integration capacitance and 25μs integration time. It＇s output voltage swing is 0 ~2.25 V,and the structure has a large linearity no less than 99%.