Multi-million frames/s sensor circuits for pulsed-source imaging

Two CMOS image sensor circuit prototypes, capable of 4 M-frames/s to 400 M-frames/s and up to 79 dB (13 bits), rms, dynamic range have been fabricated and tested. These developments are intended for the capture of fast, brief, transient events with high resolution. Applications include accelerator-based flash radiography such as proton radiography. The first is a small 2-D prototype in which each pixel includes either a capacitive trans-impedance amplifier or a direct-integration source-follower front end, followed by an array of 64 frame storage sample capacitors and associated readout electronics. The acquisition of either 32 frames using correlated double sampling (CDS) at 4 M-frames/s, or 64 frames without CDS at up to 10 Mframes/s, and up to 13 bits dynamic range was achieved. The second is a monolithic solid state "streak camera," a 1-D linear array of 150 photodiodes, with a 150-frame deep analog storage array. This device reached 400 MHz operation with electrical test inputs, at least 100 MHz operation with optical inputs, and achieves over 11 bits of dynamic range. These circuits demonstrate the high performance possible with CMOS sensor circuits containing in-situ frame storage.