2.1.1 e2v CCD44-82s in the 4Kx4K SOAR Imager (SOI)
CCD44-82s (see Fig. 2) are 3-edge buttable and have an extra FET output buffer, hence 2 output drain voltages are used: V_JD and V_OD. This CCD has two output gates and also a dump drain. A 4^4 binned image is read out in 6 sec (@ RON of 3.8e-). At the telescope, images show fringing of < 2% in the I band. No after- images are seen.
2.1.2 MIT/LL CCID20s in the 4Kx4K Mosaic for the Goodman Spectrograph
The CCID20 (see Fig. 2) uses high-resistivity bulk silicon thinned to 40 ^m with an associated red QE boost and less fringing due to a greater thickness. This 3-side buttable CCD is back-illuminated but not MPP. For the CCID20 we get a lowest noise of 1.9e- at a conversion gain of 0.4e- /ADU. We have treated the CCID20 with dry air and heat to solve cosmetic problems and attempt to increase QE.
The CCID20 requires sequencing of reset and drain voltages on power up and power down. The output drain should be the last to be turned on and the first to be turned off.
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