In this thesis, noise reduction in ROIC for uncooled pyroelectric infrared detector has been studied.
Generally, ROICs for uncooled pyroelectric infrared detector are classified in voltage follower circuit and amplifier circuit. Circuits using amplifier have advantage of responsivity, but noise problem occurs because of using amplifier. In this thesis, noise reduction in ROIC by using low-pass filter.
Proposed ROIC has large area preamp to reduce 1/f noise and low-pass filter which is connected between input and output to cutoff noise bandwidth. This circuit is fabricated in 100um*100um and biased by 50uA current. This circuit has 10 times smaller noise than preamp without filter and about 4 times smaller noise than generally used CSA circuit.
This circuit was fabricated by Hynix 0.6um 2-poly 3-metal process. Fabricated chip matches AC simulated results well. In circumstances where bandwidth of noise measurement system was limited to 102.4KHz, this fabricated chip shows about 3 times lower noise characteristic.