We present preamplifiers for frequencies from dc to few 10 MHz operating over temperature range from 300 to 4.2 K. Typical application of these circuits which use CMOS operational amplifiers is to match high impedance cryogenic sensors with low impedance cables to lead out a signal to room temperature electronics without bandwidth limiting while preserve signal to noise ratio and linearity.
Temperature dependence of electrical characteristics is shown including dissipated power and input voltage noise density spectra.