XIS Noise ProblemXIS Noise Problem

2004/3/162004/3/16

K.HayashidaK.Hayashida

Various kinds of NoiseVarious kinds of Noise

Stripe Noise Stripe Noise Band Noise type1Band Noise type1Band Noise type2Band Noise type2Jan9 event Jan9 event Kyoto FM-S1 NoiseKyoto FM-S1 NoisePSum 5 columns’ cycle noisePSum 5 columns’ cycle noise

Stripe NoiseStripe NoiseDummy CCD FM-S3

60Hz, 18KHz by Steve-sanObserved at MIT, too

Band Noise type1Band Noise type1

Dummy CCDDummy CCD200rows near Serial 200rows near Serial

registerregister5-50ADU drop in 5-50ADU drop in

pixel levelpixel levelFrequency 2~3/Frequency 2~3/ ２２

00-13/200(Depends 00-13/200(Depends on PSU-12V current on PSU-12V current limitlimit ））

Band Noise type2Band Noise type2EMAE+EU-SEMAE+EU-S (FM-AE3+FM-S2)+u-(FM-AE3+FM-S2)+u-

code with CIcode with CINo particular locationNo particular location

10frames / 100frames

P-sum mode P-sum mode ５５ columns cycle columns cycle noisenoise

P-sum PRAM P-sum PRAM used in Japan is used in Japan is different from that different from that used in MIT. The used in MIT. The bottom row of bottom row of Imaging area is Imaging area is used. used.

Jan9 eventJan9 event FM-S2+FM-AE2FM-S2+FM-AE2 Jan6-Jan9 noise Jan6-Jan9 noise

level variable. level variable. 21:15 Jan9 big 21:15 Jan9 big jump in the leveljump in the level

In Jan14 RT In Jan14 RT experiment, experiment, recovered to recovered to ~2ADU~2ADU

No particular No particular pattern in the pattern in the frame imageframe image

Kyoto Kyoto ＦＭＳ１ ＦＭＳ１ Noise Noise

RMS~ 3-4 RMS~ 3-4 ADUADU

Variable Variable frame to frame to frameframe

RMS~2ADRMS~2ADU in Osaka U in Osaka Experiment Experiment with higher with higher current limitcurrent limit

CimbinationCimbination PRAMPRAM 、、 CICI ＰＳＵ ＰＳＵ related issuerelated issue その他その他

StripesStripes Stronger in FM-AE2Stronger in FM-AE2３３ than than ＥＭＥＭEven withdumyyCCDEven withdumyyCCD

Band type1Band type1

（２００（２００ rows near rows near serial registerserial register ））

FM-AE2+dummyFM-AE2+dummy

FM-AE3+dummyFM-AE3+dummy

EM-AE+dummyEM-AE+dummy

Not visible when Not visible when we set parallel we set parallel clock to be zero Vclock to be zero V

-12V PSU voltage drop was -12V PSU voltage drop was observedobserved

Frequency increased with Frequency increased with lower -12V current limit lower -12V current limit

Kyoto Kyoto ＦＭ－Ｓ１ＦＭ－Ｓ１ FM-AE1FM-AE1 ?? Not visible with larger Not visible with larger current limit at Osakacurrent limit at Osaka

Jan9 eventJan9 event FM-AE2+FM-S2FM-AE2+FM-S2 Noise level Noise level increased and increased and variesvaries

+24V +24V ＰＳＵ ＰＳＵ voltage drop voltage drop was observed was observed

With higher PSU current With higher PSU current limit, not visible during on limit, not visible during on week experimentweek experiment

Band type2Band type2

（（ randome locatiorandome locationn ））

FM-AE3+FM-S2FM-AE3+FM-S2 PRAM without CI PRAM without CI eliminated this eliminated this noise noise

Appeared even with higher Appeared even with higher PSU current limitPSU current limit

EM-AE+EU-SEM-AE+EU-S CRT off CRT off eliminateeliminated this noid this noisese