Ocean Optics PC2000-PC_104 - Manual (Page 5)

PC2000-PC/104 Data Sheet
Interface Information
Pixel Definition
A series of pixels in the beginning of the scan have been covered with an opaque material to
compensate for thermal induced drift of the baseline signal. As the PC2000-PC/104 warms up, the
baseline signal will shift slowly downward a few counts depending on the external environment.
(Temperature-regulated units do not exhibit this shift.) The baseline signal is set between 50 and 100
counts at the time of manufacture. If the baseline signal is manually adjusted, it should be left high
enough to allow for system drift. The following is a description of all of the pixels:
Pixel Description
0–1 Not usable
2–24 Optical black pixels
24–25 Transition pixels
26–2674 Optical active pixels
It is important to note that Ocean Optics A/D products only digitize the first 2048 pixels, as they all
have a 2048 x 16 FIFO buffer.
Analog Section
The PC2000-PC/104 is capable of supporting the output of up to 8 spectrometer channels (master
channel plus 7 slave channels). The spectrometer channel is determined by switch SW2. Within a
stack, there should be only one spectrometer on any given channel. The master spectrometer is
hardwired to the master channel (channel 0). Each spectrometer generates an analog signal (-2.5 -
+2.5V), which corresponds to the input spectra.
Clock Signals
Master Clock
The frequency of this clock is set via software. The A/D rate is one-half that of the Master Clock. The
maximum rate for the Master Clock is 4MHz, which equates to an A/D rate of 2 MHz. A
recommended minimum frequency is 100 kHz.
Integration Clock
The frequency of this clock is set via software. The period for the integration time clock should be
longer than 4100 master clock periods in order to read the entire array. This equates to 1.1ms.
000-00000-000-05-0704 5