New field effect devices with linear V-I characteristics

A new field effect device which shows the linear relation between the drain voltage(V) and current(I) in the operational range of drain voltage more than ±10 volts has been studied and developed. This device has the special gate structure composed of the semi-insulated polycrystalline silicon resistive layer. Typical electrical characteristics of this device applied to the L-type gain control circuits were measured as follows; 1) the extremely low harmonic distortion less than 0.02 % at 6 db attenuation for the in-put signal level of 0 dbm at 1 KHz, 2) the large attenuation more than 80 db for the large in-put signal level of 20 dbm. This device will be an useful tool to expand the dynamic range and the improvement of circuit characteristics in the gain control circuits and will also be applied for new multi-channel analog switching devices without the tracking error.