  Current Sensitive Preamplifiers (CSPs) are widely used in front-end
electronics in data acquire system (DAQ), due to their ability to amplify
signals directly. The optimization of energy resolution requires CSPs with
suitable parameters such as gain, bandwidth, and low noise, etc. With the rapid
improvement of CSP's bandwidth and trans-impedance gain, it is necessary to
know how does the output noise of CSPs effect the energy resolution. For this
purpose, we built the noise model of CSPs and analyzed the output noise voltage
density of CSPs based on different commercial operation amplifiers (OP AMPs).
Theoretical and experimental results shown that OP AMPs with low input noise
voltage density is superior than others on energy resolution. Moreover, noise
normalization factor has been defined to verify the relationship between energy
resolution and noise of CSPs. The experimental results shown that the energy
resolution and noise normalization factor are linearly conformable. This paper
can provide reference on selecting commercial OP AMPs to design CSPs for
optimization of energy resolution.
