Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
96 words
A charge sensitive preamplifier without a resistor or resistance components in parallel with a feedback capacitor for amplifying a charge delivered by a detector comprising: an input cascode having a first and a second transistor, the second transistor behaving as being in a common base configuration; first feedback means comprising a capacitor connected between an output transistor and said detector, for performing the charge to voltage conversion; and second feedback means, connected between said output transistor and the base of the second transistor of said input cascode, for stabilizing the DC operating point of said preamplifier.
Claim 2
Dependent Claim
96 words
A charge sensitive preamplifier without a resistor or resistance components in parallel with a feedback capacitor for amplifying a charge delivered by a detector comprising: an input cascode having a first and a second transistor, the second transistor behaving as being in a common base configuration; first feedback means comprising a capacitor connected between an output transistor and said detector, for performing the charge to voltage conversion; and second feedback means, connected between said output transistor and the base of the second transistor of said input cascode, for stabilizing the DC operating point of said preamplifier.
Claim 3
Dependent Claim
16 words
The apparatus of claim 1 wherein said first transistor of the input cascode comprises a JFET.
Claim 4
Dependent Claim
14 words
The apparatus of claim 2 wherein said JFET has its gate-source junction forward biased.
Claim 5
Dependent Claim
26 words
The apparatus of claim 3 wherein said JFET collects all the leakage current from said detector and from the gate to drain junction of said JFET.
Claim 6
Dependent Claim
12 words
The apparatus of claim 4 wherein said JFET is a N-channel type.
Claim 7
Dependent Claim
12 words
The apparatus of claim 4 wherein said JFET is a P-channel type.
Claim 8
Dependent Claim
110 words
A charge sensitive preamplifier without a resistor in parallel with a feedback capacitor for amplifying a charge delivered by a detector comprising: an input cascode having a first and a second transistor, the second transistor behaving as being in a common base configuration; first feedback means comprising a capacitor connected between an output transistor and said detector, for performing the charge to voltage conversion; and a second feedback loop comprising a low-pass filter connected between the output of the preamplifier and the input cascode of said first transistor for lowering the DC voltage gain and stabilizing the operating point of said preamplifier, while maintaining a high middle band voltage gain.
Claim 9
Dependent Claim
110 words
A charge sensitive preamplifier without a resistor in parallel with a feedback capacitor for amplifying a charge delivered by a detector comprising: an input cascode having a first and a second transistor, the second transistor behaving as being in a common base configuration; first feedback means comprising a capacitor connected between an output transistor and said detector, for performing the charge to voltage conversion; and a second feedback loop comprising a low-pass filter connected between the output of the preamplifier and the input cascode of said first transistor for lowering the DC voltage gain and stabilizing the operating point of said preamplifier, while maintaining a high middle band voltage gain.
Claim 10
Dependent Claim
25 words
The apparatus of claim 7 wherein said low-pass filter comprises a capacitor that is effective to cut off high frequency components of the output signal.
Claim 11
Dependent Claim
34 words
The apparatus of claim 7 wherein said low-pass filter does not permit the DC and low frequency components of the detector current feeding the preamplifier to significantly charge the feedback capacitor of the preamplifier.
Claim 12
Dependent Claim
34 words
The apparatus of claim 7 wherein said second feedback loop operates to lower the DC voltage gain of the preamplifier to permit its input voltage to vary in the range of hundreds of millivolts.