... the analog plusTM compa
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PRELIMINARY
Figure 13. Gray-scale Target Scan
22.To demonstrate the noise component is contributed from the CIS, we hooked up a DC reference to the scanner and the results are shown below in Table 1.
REFERENCE DC (V) | STANDARD DEVIATION | SYSTEM SNR (dB) W/O CIS |
|
| NOISE COMPONENT |
|
|
|
2.0 | 2.144328 | 62.6117 |
2.5 | 3.48261 | 58.3988 |
3.0 | 2.399188 | 61.6356 |
3.5 | 1.983461 | 63.28842 |
Table 1.
As we can see from Table 1, the SNR falls into the range of 58 dB to 63 dB when a DC reference is used as input to the XRD9827REF. The system alone gives a 9 1/2 to 10 bit performance. The largest noise source we saw in previous scans came from the CIS. A typical plot of the DC reference is shown in Figure 14.
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