Device Identification
Chip name EEV10a
Year of manufacture 1997
Serial number 7043-16-4
First light on La Palma March 1998
Description EEV42 thinned.
Modifications to EEV10a by SMT 27th May 1999
There were a number of problems with the original
EEV10a related to poor noise performance and poor matching of the signal
processor gain to the dynamic range of the CCD. The following hardware
modifications were made.
1. The outer sheath of the
short grey cable connecting cryostat to pre-amp was grounded to pre-amp
chassis.
2. R31,32,33,34 in the pre-amp
all has 4K7 resistors soldered in parallel.
3. R5 on the CDS was replaced
with 50K.
4. R12 & R13 on the CDS
were replaced with 3K9
5. C7,C8 on CDS card were replaced
with 1000pF
The standard, Quick and Turbo pixel routines ( pages 9,10 & 11 of ram-disk ) were replaced with those used on EEV12. The RD voltage was increased to 4.5V and OD reduced to 16V. THe rest of the RAM-DISK was unchanged.
The effect of the changes was to reduce the read
noise, remove pattern noise, decrease the readout time and increase the
dynamic range.
Operational Characteristics ( effective 27 May 1999 )
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Vertical CTE >0.999999
Horizontal CTE >0.999999
Physical Characteristics
Pixel Scale (isis blue) 0.19 arcsecs/pixel
X Pixel size 13.5 microns
Y Pixel size 13.5 microns
X size in pixels of digitised area 2148
Y size in pixels of digitised area 4148
X size of useful imaging area 2048
Y size of useful imaging area 4100
X start of useful imaging area 50
Y start of useful imaging area 0
LN2 capacity of cryostat 2.5 litres
Cryostat window thickness 4 mm
Distance from window to CCD 10 mm
Cryostat window size 36 x 66 mm
Operational Parameters
Operating temperature 153K
Preferred amplifier L( R provides the same performance )
Network name CCD1
Anti-blooming available no
Measured characteristics
Quantum Efficiency
Full QE curve for EEV4280 in tabulated form, measured at ATC March 99
Dark current 4 e/hour @ -120 degrees C
Full well bloom limit ~150000 electrons
Chip flatness Profile scan shows centre section to be flat to < 1 micron
Cosmetics There are about 2ish pixel/column defects plus a cluster of single pixel defects.
Cosmic Ray count 1.6 events/cm2/min.