| 摘要 |
A circuit using amplification stages (VS1, VS2) with MOS tetrodes (SE1, SE2) to switch the ranges between various bands (UHF, VHF) in television receivers, whereby the operating point of said tetrodes is easy to adjust. The MOS tetrodes included in the inventive circuit have a constant potential on their source electrode that is independent from the selected range. The amplification stages (VS1, VS2) are activated by means of control electrodes (GA1, GB1, GA2, GB2) pertaining to the respective MOS-tetrodes. In addition to achieving savings in components, the invention simplifies the dimensions of the circuit. The invention can be used in all types of high frequency receivers having various frequency ranges that require switching.
|
