Voltage to current converter for a grounded load.

My recent experience in searching for information on this topic on the web was fairly negative. The reason for the search was to use a translinear circuit in my system design. Translinear circuits work on currents so a voltage to current converter is required at the input. ( Perhaps a current to voltage converter on the output. Simplest being a resistance). There is not a lot of information on V to I converters on the web specially if you are looking for a simple one. I found one that seemed to be popular and simulated it on LTSPICE. Its quite complicated and uses an opamp or two. Still searching for a simpler one which would be compatible with device level translinear circuits. Ultimately looks like I may need to design one.