This paper reports the development of a new microbolometer Readout Integrated Circuit (ROIC) called MT3825BA. It has a format of 384 × 288 and a pixel pitch of 25µm. MT3825BA is Mikro-Tasarim's second microbolometer ROIC product, which is developed specifically for resistive surface micro-machined microbolometer detector arrays using high-TCR pixel materials, such as VO x and a-Si. MT3825BA has a system-on-chip architecture, where all the timing, biasing, and pixel non-uniformity correction (NUC) operations in the ROIC are applied using on-chip circuitry simplifying the use and system integration of this ROIC. The ROIC is designed to support pixel resistance values ranging from 30 KΩ to 100 KΩ. MT3825BA is operated using conventional row based readout method, where pixels in the array are read out in a row-by-row basis, where the applied bias for each pixel in a given row is updated at the beginning of each line period according to the applied line based NUC data. The NUC data is applied continuously in a row-by-row basis using the serial programming interface, which is also used to program user configurable features of the ROIC, such as readout gain, integration time, and number of analog video outputs. MT3825BA has a total of 4 analog video outputs and 2 analog reference outputs, placed at the top and bottom of the ROIC, which can be programmed to operate in the 1, 2, and 4-output modes, supporting frames rates well above 60 fps at a 3 MHz pixel output rate. The pixels in the array are read out with respect to reference pixels implemented above and below actual array pixels. The bias voltage of the pixels can be programmed over a 1.0 V range to compensate for the changes in the detector resistance values due to the variations coming from the manufacturing process or changes in the operating temperature. The ROIC has an on-chip integrated temperature sensor with a sensitivity of better than 5 mV / K, and the output of the temperature sensor can be read out the output as part of the analog video stream. MT3825BA can be used to build a microbolometer FPAs with an NETD value below 100 mK using a microbolometer detector array fabrication technology with a detector resistance value up to 100 KΩ, a high TCR value (> 2 % / K), and a sufficiently low pixel thermal conductance (G th ≤ 20 nW / K). MT3825BA measures 13.0 mm × 13.5 mm and is fabricated on 200 mm CMOS wafers. The microbolometer ROIC wafers are engineered to have flat surface finish to simplify the wafer level detector fabrication and wafer level vacuum packaging (WLVP). The ROIC runs on 3.3 V analog and 1.8 V digital supplies, and dissipates less than 85 mW in the 2-output mode at 30 fps. Mikro-Tasarim provides tested ROIC wafers and offers compact test electronics and software for its ROIC customers to shorten their FPA and camera development cycles.

This paper reports the development of a new SXGA format low-noise CTIA ROIC (MT12815CA-3G) suitable for mega-pixel SWIR InGaAs detector arrays for low-light imaging applications. MT12815CA-3G is the first mega-pixel standard ROIC product from Mikro-Tasarim, which is a fabless semiconductor company specialized in the development of ROICs and ASICs for visible and infrared hybrid imaging sensors. MT12815CA-3G is a low-noise snapshot mega-pixel CTIA ROIC, has a format of 1280 × 1024 (SXGA) and pixel pitch of 15 µm. MT12815CA-3G has been developed with the system-on-chip architecture in mind, where all the timing and biasing for this ROIC are generated on-chip without requiring any special external inputs. MT12815CA-3G is a highly configurable ROIC with many features that can be programmed through a 3-wire serial interface allowing on-the-fly configuration the ROIC. It performs snapshot operation both using Integrate-Then-Read (ITR) and Integrate-While-Read (IWR) modes. The CTIA type pixel input circuitry has 3 gain modes with programmable full-well-capacity (FWC) values of 10K e-, 20K e-, and 350K e-in the very high gain (VHG), high-gain (HG), and low-gain (LG) modes, respectively. MT12815CA-3G has an input referred noise level of less than 5 e-in the very high gain (VHG) mode, suitable for very low-noise SWIR imaging applications. MT12815CA-3G has 8 analog video outputs that can be programmed in 8, 4, or 2-output modes with a selectable analog reference for pseudo-differential operation. The ROIC runs at 10 MHz and supports frame rate values up to 55 fps in the 8-output mode. The integration time of the ROIC can be programmed up to 1s in steps of 0.1 µs. The ROIC uses 3.3 V and 1.8V supply voltages and dissipates less than 350 mW in the 4-output mode. MT12815CA-3G is fabricated using a modern mixed-signal CMOS process on 200 mm CMOS wafers, and there are 44 ROIC parts per wafer. The probe tests show that the die yield is higher than 70%, which corresponds to more than 30 working ROIC parts per wafer typically. MT12815CA-3G ROIC is available as tested wafers or dies, where a detailed test report and wafer map are provided for each wafer. A compact USB 3.0 based test camera and imaging software are also available for the customers to test and evaluate the imaging performance of SWIR sensors built using MT12815CA-3G ROICs. Mikro-Tasarim has also recently developed a programmable mixed-signal application specific integrated circuit (ASIC), called MTAS1410X8, which is designed to perform ROIC driving and digitization functions for ROICs with analog outputs, such as MT12815CA-3G and MT6415CA ROIC products of Mikro-Tasarim. MTAS1410X8 has 8 simultaneously working 14-bit analog-to-digital converters (ADCs) with integrated programmable gain amplifiers (PGAs), video input buffers, programmable controller, and high-speed digital video interface supporting various formats including Camera Link. MT12815CA-3G ROIC together with MTAS1410X8 ASIC can be used to develop low-noise high-resolution SWIR imaging sensors with low power d...

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