Design of voltage-controlled linear transconductance elements with a method pair of FET transistors

Using a matched pair of junction or depletion MOS field -effect transistors (FET's) is proposed for realizing a voltage-controlled linear transconductance element (VCLTE). Its application allows one to increase the linear input voltage range compared with a single FET. It is interesting that it is possible in the same circuit to obtain positive or negative values of transconductance. The resulting circuit is easy to implement and is stable. Some experimental results are presented.