microDXP Technical Reference Manual
Version 3.15
October 7, 2019
48
Figure 4-1:
a)
Reset-type charge sensitive preamplifier with a negatively biased detector;
b)
Output on absorption of x-ray rays. Note that the steps have a rising edge, so that the
signal polarity is positive.
Figure 4-2 depicts the large-signal saw tooth waveform that results from successive x-ray
steps followed by the reset. Note that the units here are Volts and milliseconds vs. millivolts
and microseconds in the previous figure.
Figure 4-2: The large-signal reset waveform for a reset-type preamplifier with positive signal
polarity, as displayed on a real oscilloscope. Note that the large signal character is not
displayed in the microDXP diagnostic trace readout, e.g. used in ProSpect’s
Scope
diagnostic tool, looks quite different because of the dynamic range reduction carried
out in the ASC, as described in §3.2.1.
